diff --git a/samples/client/petstore/java/jersey2-java8/.gitignore b/samples/client/petstore/java/jersey2-java8/.gitignore
new file mode 100644
index 000000000000..a530464afa1b
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/.gitignore
@@ -0,0 +1,21 @@
+*.class
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.ear
+
+# exclude jar for gradle wrapper
+!gradle/wrapper/*.jar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+# build files
+**/target
+target
+.gradle
+build
diff --git a/samples/client/petstore/java/jersey2-java8/.openapi-generator-ignore b/samples/client/petstore/java/jersey2-java8/.openapi-generator-ignore
new file mode 100644
index 000000000000..7484ee590a38
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/.openapi-generator-ignore
@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md
diff --git a/samples/client/petstore/java/jersey2-java8/git_push.sh b/samples/client/petstore/java/jersey2-java8/git_push.sh
new file mode 100644
index 000000000000..ced3be2b0c7b
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/git_push.sh
@@ -0,0 +1,58 @@
+#!/bin/sh
+# ref: https://help.github.com/articles/adding-an-existing-project-to-github-using-the-command-line/
+#
+# Usage example: /bin/sh ./git_push.sh wing328 openapi-pestore-perl "minor update" "gitlab.com"
+
+git_user_id=$1
+git_repo_id=$2
+release_note=$3
+git_host=$4
+
+if [ "$git_host" = "" ]; then
+    git_host="github.com"
+    echo "[INFO] No command line input provided. Set \$git_host to $git_host"
+fi
+
+if [ "$git_user_id" = "" ]; then
+    git_user_id="GIT_USER_ID"
+    echo "[INFO] No command line input provided. Set \$git_user_id to $git_user_id"
+fi
+
+if [ "$git_repo_id" = "" ]; then
+    git_repo_id="GIT_REPO_ID"
+    echo "[INFO] No command line input provided. Set \$git_repo_id to $git_repo_id"
+fi
+
+if [ "$release_note" = "" ]; then
+    release_note="Minor update"
+    echo "[INFO] No command line input provided. Set \$release_note to $release_note"
+fi
+
+# Initialize the local directory as a Git repository
+git init
+
+# Adds the files in the local repository and stages them for commit.
+git add .
+
+# Commits the tracked changes and prepares them to be pushed to a remote repository.
+git commit -m "$release_note"
+
+# Sets the new remote
+git_remote=`git remote`
+if [ "$git_remote" = "" ]; then # git remote not defined
+
+    if [ "$GIT_TOKEN" = "" ]; then
+        echo "[INFO] \$GIT_TOKEN (environment variable) is not set. Using the git credential in your environment."
+        git remote add origin https://${git_host}/${git_user_id}/${git_repo_id}.git
+    else
+        git remote add origin https://${git_user_id}:${GIT_TOKEN}@${git_host}/${git_user_id}/${git_repo_id}.git
+    fi
+
+fi
+
+git pull origin master
+
+# Pushes (Forces) the changes in the local repository up to the remote repository
+echo "Git pushing to https://${git_host}/${git_user_id}/${git_repo_id}.git"
+git push origin master 2>&1 | grep -v 'To https'
+
diff --git a/samples/client/petstore/java/jersey2-java8/gradlew b/samples/client/petstore/java/jersey2-java8/gradlew
new file mode 100644
index 000000000000..af6708ff229f
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/gradlew
@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/samples/client/petstore/java/jersey2-java8/gradlew.bat b/samples/client/petstore/java/jersey2-java8/gradlew.bat
new file mode 100644
index 000000000000..f9553162f122
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/gradlew.bat
@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
new file mode 100644
index 000000000000..a06ca6f8d63d
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
@@ -0,0 +1,809 @@
+package org.openapitools.client;
+
+import javax.ws.rs.client.Client;
+import javax.ws.rs.client.ClientBuilder;
+import javax.ws.rs.client.Entity;
+import javax.ws.rs.client.Invocation;
+import javax.ws.rs.client.WebTarget;
+import javax.ws.rs.core.Form;
+import javax.ws.rs.core.GenericType;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.core.Response.Status;
+
+import org.glassfish.jersey.client.ClientConfig;
+import org.glassfish.jersey.client.ClientProperties;
+import org.glassfish.jersey.client.HttpUrlConnectorProvider;
+import org.glassfish.jersey.jackson.JacksonFeature;
+import org.glassfish.jersey.media.multipart.FormDataBodyPart;
+import org.glassfish.jersey.media.multipart.FormDataContentDisposition;
+import org.glassfish.jersey.media.multipart.MultiPart;
+import org.glassfish.jersey.media.multipart.MultiPartFeature;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import java.nio.file.Files;
+import java.nio.file.StandardCopyOption;
+import org.glassfish.jersey.logging.LoggingFeature;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.HashMap;
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.TimeZone;
+
+import java.net.URLEncoder;
+
+import java.io.File;
+import java.io.UnsupportedEncodingException;
+
+import java.text.DateFormat;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.openapitools.client.auth.Authentication;
+import org.openapitools.client.auth.HttpBasicAuth;
+import org.openapitools.client.auth.HttpBearerAuth;
+import org.openapitools.client.auth.ApiKeyAuth;
+import org.openapitools.client.auth.OAuth;
+
+
+public class ApiClient {
+  protected Map<String, String> defaultHeaderMap = new HashMap<String, String>();
+  protected String basePath = "http://petstore.swagger.io:80/v2";
+  protected boolean debugging = false;
+  protected int connectionTimeout = 0;
+  private int readTimeout = 0;
+
+  protected Client httpClient;
+  protected JSON json;
+  protected String tempFolderPath = null;
+
+  protected Map<String, Authentication> authentications;
+
+  protected DateFormat dateFormat;
+
+  public ApiClient() {
+    json = new JSON();
+    httpClient = buildHttpClient(debugging);
+
+    this.dateFormat = new RFC3339DateFormat();
+
+    // Set default User-Agent.
+    setUserAgent("OpenAPI-Generator/1.0.0/java");
+
+    // Setup authentications (key: authentication name, value: authentication).
+    authentications = new HashMap<String, Authentication>();
+    authentications.put("api_key", new ApiKeyAuth("header", "api_key"));
+    authentications.put("api_key_query", new ApiKeyAuth("query", "api_key_query"));
+    authentications.put("http_basic_test", new HttpBasicAuth());
+    authentications.put("petstore_auth", new OAuth());
+    // Prevent the authentications from being modified.
+    authentications = Collections.unmodifiableMap(authentications);
+  }
+
+  /**
+   * Gets the JSON instance to do JSON serialization and deserialization.
+   * @return JSON
+   */
+  public JSON getJSON() {
+    return json;
+  }
+
+  public Client getHttpClient() {
+    return httpClient;
+  }
+
+  public ApiClient setHttpClient(Client httpClient) {
+    this.httpClient = httpClient;
+    return this;
+  }
+
+  public String getBasePath() {
+    return basePath;
+  }
+
+  public ApiClient setBasePath(String basePath) {
+    this.basePath = basePath;
+    return this;
+  }
+
+  /**
+   * Get authentications (key: authentication name, value: authentication).
+   * @return Map of authentication object
+   */
+  public Map<String, Authentication> getAuthentications() {
+    return authentications;
+  }
+
+  /**
+   * Get authentication for the given name.
+   *
+   * @param authName The authentication name
+   * @return The authentication, null if not found
+   */
+  public Authentication getAuthentication(String authName) {
+    return authentications.get(authName);
+  }
+
+  /**
+   * Helper method to set username for the first HTTP basic authentication.
+   * @param username Username
+   */
+  public void setUsername(String username) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof HttpBasicAuth) {
+        ((HttpBasicAuth) auth).setUsername(username);
+        return;
+      }
+    }
+    throw new RuntimeException("No HTTP basic authentication configured!");
+  }
+
+  /**
+   * Helper method to set password for the first HTTP basic authentication.
+   * @param password Password
+   */
+  public void setPassword(String password) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof HttpBasicAuth) {
+        ((HttpBasicAuth) auth).setPassword(password);
+        return;
+      }
+    }
+    throw new RuntimeException("No HTTP basic authentication configured!");
+  }
+
+  /**
+   * Helper method to set API key value for the first API key authentication.
+   * @param apiKey API key
+   */
+  public void setApiKey(String apiKey) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof ApiKeyAuth) {
+        ((ApiKeyAuth) auth).setApiKey(apiKey);
+        return;
+      }
+    }
+    throw new RuntimeException("No API key authentication configured!");
+  }
+
+  /**
+   * Helper method to set API key prefix for the first API key authentication.
+   * @param apiKeyPrefix API key prefix
+   */
+  public void setApiKeyPrefix(String apiKeyPrefix) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof ApiKeyAuth) {
+        ((ApiKeyAuth) auth).setApiKeyPrefix(apiKeyPrefix);
+        return;
+      }
+    }
+    throw new RuntimeException("No API key authentication configured!");
+  }
+
+  /**
+   * Helper method to set bearer token for the first Bearer authentication.
+   * @param bearerToken Bearer token
+   */
+  public void setBearerToken(String bearerToken) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof HttpBearerAuth) {
+        ((HttpBearerAuth) auth).setBearerToken(bearerToken);
+        return;
+      }
+    }
+    throw new RuntimeException("No Bearer authentication configured!");
+  }
+
+  /**
+   * Helper method to set access token for the first OAuth2 authentication.
+   * @param accessToken Access token
+   */
+  public void setAccessToken(String accessToken) {
+    for (Authentication auth : authentications.values()) {
+      if (auth instanceof OAuth) {
+        ((OAuth) auth).setAccessToken(accessToken);
+        return;
+      }
+    }
+    throw new RuntimeException("No OAuth2 authentication configured!");
+  }
+
+  /**
+   * Set the User-Agent header's value (by adding to the default header map).
+   * @param userAgent Http user agent
+   * @return API client
+   */
+  public ApiClient setUserAgent(String userAgent) {
+    addDefaultHeader("User-Agent", userAgent);
+    return this;
+  }
+
+  /**
+   * Add a default header.
+   *
+   * @param key The header's key
+   * @param value The header's value
+   * @return API client
+   */
+  public ApiClient addDefaultHeader(String key, String value) {
+    defaultHeaderMap.put(key, value);
+    return this;
+  }
+
+  /**
+   * Check that whether debugging is enabled for this API client.
+   * @return True if debugging is switched on
+   */
+  public boolean isDebugging() {
+    return debugging;
+  }
+
+  /**
+   * Enable/disable debugging for this API client.
+   *
+   * @param debugging To enable (true) or disable (false) debugging
+   * @return API client
+   */
+  public ApiClient setDebugging(boolean debugging) {
+    this.debugging = debugging;
+    // Rebuild HTTP Client according to the new "debugging" value.
+    this.httpClient = buildHttpClient(debugging);
+    return this;
+  }
+
+  /**
+   * The path of temporary folder used to store downloaded files from endpoints
+   * with file response. The default value is <code>null</code>, i.e. using
+   * the system's default tempopary folder.
+   *
+   * @return Temp folder path
+   */
+  public String getTempFolderPath() {
+    return tempFolderPath;
+  }
+
+  /**
+   * Set temp folder path
+   * @param tempFolderPath Temp folder path
+   * @return API client
+   */
+  public ApiClient setTempFolderPath(String tempFolderPath) {
+    this.tempFolderPath = tempFolderPath;
+    return this;
+  }
+
+  /**
+   * Connect timeout (in milliseconds).
+   * @return Connection timeout
+   */
+  public int getConnectTimeout() {
+    return connectionTimeout;
+  }
+
+  /**
+   * Set the connect timeout (in milliseconds).
+   * A value of 0 means no timeout, otherwise values must be between 1 and
+   * {@link Integer#MAX_VALUE}.
+   * @param connectionTimeout Connection timeout in milliseconds
+   * @return API client
+   */
+  public ApiClient setConnectTimeout(int connectionTimeout) {
+    this.connectionTimeout = connectionTimeout;
+    httpClient.property(ClientProperties.CONNECT_TIMEOUT, connectionTimeout);
+    return this;
+  }
+
+  /**
+   * read timeout (in milliseconds).
+   * @return Read timeout
+   */
+  public int getReadTimeout() {
+    return readTimeout;
+  }
+  
+  /**
+   * Set the read timeout (in milliseconds).
+   * A value of 0 means no timeout, otherwise values must be between 1 and
+   * {@link Integer#MAX_VALUE}.
+   * @param readTimeout Read timeout in milliseconds
+   * @return API client
+   */
+  public ApiClient setReadTimeout(int readTimeout) {
+    this.readTimeout = readTimeout;
+    httpClient.property(ClientProperties.READ_TIMEOUT, readTimeout);
+    return this;
+  }
+
+  /**
+   * Get the date format used to parse/format date parameters.
+   * @return Date format
+   */
+  public DateFormat getDateFormat() {
+    return dateFormat;
+  }
+
+  /**
+   * Set the date format used to parse/format date parameters.
+   * @param dateFormat Date format
+   * @return API client
+   */
+  public ApiClient setDateFormat(DateFormat dateFormat) {
+    this.dateFormat = dateFormat;
+    // also set the date format for model (de)serialization with Date properties
+    this.json.setDateFormat((DateFormat) dateFormat.clone());
+    return this;
+  }
+
+  /**
+   * Parse the given string into Date object.
+   * @param str String
+   * @return Date
+   */
+  public Date parseDate(String str) {
+    try {
+      return dateFormat.parse(str);
+    } catch (java.text.ParseException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  /**
+   * Format the given Date object into string.
+   * @param date Date
+   * @return Date in string format
+   */
+  public String formatDate(Date date) {
+    return dateFormat.format(date);
+  }
+
+  /**
+   * Format the given parameter object into string.
+   * @param param Object
+   * @return Object in string format
+   */
+  public String parameterToString(Object param) {
+    if (param == null) {
+      return "";
+    } else if (param instanceof Date) {
+      return formatDate((Date) param);
+    } else if (param instanceof Collection) {
+      StringBuilder b = new StringBuilder();
+      for(Object o : (Collection)param) {
+        if(b.length() > 0) {
+          b.append(',');
+        }
+        b.append(String.valueOf(o));
+      }
+      return b.toString();
+    } else {
+      return String.valueOf(param);
+    }
+  }
+
+  /*
+   * Format to {@code Pair} objects.
+   * @param collectionFormat Collection format
+   * @param name Name
+   * @param value Value
+   * @return List of pairs
+   */
+  public List<Pair> parameterToPairs(String collectionFormat, String name, Object value){
+    List<Pair> params = new ArrayList<Pair>();
+
+    // preconditions
+    if (name == null || name.isEmpty() || value == null) return params;
+
+    Collection valueCollection;
+    if (value instanceof Collection) {
+      valueCollection = (Collection) value;
+    } else {
+      params.add(new Pair(name, parameterToString(value)));
+      return params;
+    }
+
+    if (valueCollection.isEmpty()){
+      return params;
+    }
+
+    // get the collection format (default: csv)
+    String format = (collectionFormat == null || collectionFormat.isEmpty() ? "csv" : collectionFormat);
+
+    // create the params based on the collection format
+    if ("multi".equals(format)) {
+      for (Object item : valueCollection) {
+        params.add(new Pair(name, parameterToString(item)));
+      }
+
+      return params;
+    }
+
+    String delimiter = ",";
+
+    if ("csv".equals(format)) {
+      delimiter = ",";
+    } else if ("ssv".equals(format)) {
+      delimiter = " ";
+    } else if ("tsv".equals(format)) {
+      delimiter = "\t";
+    } else if ("pipes".equals(format)) {
+      delimiter = "|";
+    }
+
+    StringBuilder sb = new StringBuilder() ;
+    for (Object item : valueCollection) {
+      sb.append(delimiter);
+      sb.append(parameterToString(item));
+    }
+
+    params.add(new Pair(name, sb.substring(1)));
+
+    return params;
+  }
+
+  /**
+   * Check if the given MIME is a JSON MIME.
+   * JSON MIME examples:
+   *   application/json
+   *   application/json; charset=UTF8
+   *   APPLICATION/JSON
+   *   application/vnd.company+json
+   * "* / *" is also default to JSON
+   * @param mime MIME
+   * @return True if the MIME type is JSON
+   */
+  public boolean isJsonMime(String mime) {
+    String jsonMime = "(?i)^(application/json|[^;/ \t]+/[^;/ \t]+[+]json)[ \t]*(;.*)?$";
+    return mime != null && (mime.matches(jsonMime) || mime.equals("*/*"));
+  }
+
+  /**
+   * Select the Accept header's value from the given accepts array:
+   *   if JSON exists in the given array, use it;
+   *   otherwise use all of them (joining into a string)
+   *
+   * @param accepts The accepts array to select from
+   * @return The Accept header to use. If the given array is empty,
+   *   null will be returned (not to set the Accept header explicitly).
+   */
+  public String selectHeaderAccept(String[] accepts) {
+    if (accepts.length == 0) {
+      return null;
+    }
+    for (String accept : accepts) {
+      if (isJsonMime(accept)) {
+        return accept;
+      }
+    }
+    return StringUtil.join(accepts, ",");
+  }
+
+  /**
+   * Select the Content-Type header's value from the given array:
+   *   if JSON exists in the given array, use it;
+   *   otherwise use the first one of the array.
+   *
+   * @param contentTypes The Content-Type array to select from
+   * @return The Content-Type header to use. If the given array is empty,
+   *   JSON will be used.
+   */
+  public String selectHeaderContentType(String[] contentTypes) {
+    if (contentTypes.length == 0) {
+      return "application/json";
+    }
+    for (String contentType : contentTypes) {
+      if (isJsonMime(contentType)) {
+        return contentType;
+      }
+    }
+    return contentTypes[0];
+  }
+
+  /**
+   * Escape the given string to be used as URL query value.
+   * @param str String
+   * @return Escaped string
+   */
+  public String escapeString(String str) {
+    try {
+      return URLEncoder.encode(str, "utf8").replaceAll("\\+", "%20");
+    } catch (UnsupportedEncodingException e) {
+      return str;
+    }
+  }
+
+  /**
+   * Serialize the given Java object into string entity according the given
+   * Content-Type (only JSON is supported for now).
+   * @param obj Object
+   * @param formParams Form parameters
+   * @param contentType Context type
+   * @return Entity
+   * @throws ApiException API exception
+   */
+  public Entity<?> serialize(Object obj, Map<String, Object> formParams, String contentType) throws ApiException {
+    Entity<?> entity;
+    if (contentType.startsWith("multipart/form-data")) {
+      MultiPart multiPart = new MultiPart();
+      for (Entry<String, Object> param: formParams.entrySet()) {
+        if (param.getValue() instanceof File) {
+          File file = (File) param.getValue();
+          FormDataContentDisposition contentDisp = FormDataContentDisposition.name(param.getKey())
+              .fileName(file.getName()).size(file.length()).build();
+          multiPart.bodyPart(new FormDataBodyPart(contentDisp, file, MediaType.APPLICATION_OCTET_STREAM_TYPE));
+        } else {
+          FormDataContentDisposition contentDisp = FormDataContentDisposition.name(param.getKey()).build();
+          multiPart.bodyPart(new FormDataBodyPart(contentDisp, parameterToString(param.getValue())));
+        }
+      }
+      entity = Entity.entity(multiPart, MediaType.MULTIPART_FORM_DATA_TYPE);
+    } else if (contentType.startsWith("application/x-www-form-urlencoded")) {
+      Form form = new Form();
+      for (Entry<String, Object> param: formParams.entrySet()) {
+        form.param(param.getKey(), parameterToString(param.getValue()));
+      }
+      entity = Entity.entity(form, MediaType.APPLICATION_FORM_URLENCODED_TYPE);
+    } else {
+      // We let jersey handle the serialization
+      entity = Entity.entity(obj, contentType);
+    }
+    return entity;
+  }
+
+  /**
+   * Deserialize response body to Java object according to the Content-Type.
+   * @param <T> Type
+   * @param response Response
+   * @param returnType Return type
+   * @return Deserialize object
+   * @throws ApiException API exception
+   */
+  @SuppressWarnings("unchecked")
+  public <T> T deserialize(Response response, GenericType<T> returnType) throws ApiException {
+    if (response == null || returnType == null) {
+      return null;
+    }
+
+    if ("byte[]".equals(returnType.toString())) {
+      // Handle binary response (byte array).
+      return (T) response.readEntity(byte[].class);
+    } else if (returnType.getRawType() == File.class) {
+      // Handle file downloading.
+      T file = (T) downloadFileFromResponse(response);
+      return file;
+    }
+
+    String contentType = null;
+    List<Object> contentTypes = response.getHeaders().get("Content-Type");
+    if (contentTypes != null && !contentTypes.isEmpty())
+      contentType = String.valueOf(contentTypes.get(0));
+
+    return response.readEntity(returnType);
+  }
+
+  /**
+   * Download file from the given response.
+   * @param response Response
+   * @return File
+   * @throws ApiException If fail to read file content from response and write to disk
+   */
+  public File downloadFileFromResponse(Response response) throws ApiException {
+    try {
+      File file = prepareDownloadFile(response);
+      Files.copy(response.readEntity(InputStream.class), file.toPath(), StandardCopyOption.REPLACE_EXISTING);
+      return file;
+    } catch (IOException e) {
+      throw new ApiException(e);
+    }
+  }
+
+  public File prepareDownloadFile(Response response) throws IOException {
+    String filename = null;
+    String contentDisposition = (String) response.getHeaders().getFirst("Content-Disposition");
+    if (contentDisposition != null && !"".equals(contentDisposition)) {
+      // Get filename from the Content-Disposition header.
+      Pattern pattern = Pattern.compile("filename=['\"]?([^'\"\\s]+)['\"]?");
+      Matcher matcher = pattern.matcher(contentDisposition);
+      if (matcher.find())
+        filename = matcher.group(1);
+    }
+
+    String prefix;
+    String suffix = null;
+    if (filename == null) {
+      prefix = "download-";
+      suffix = "";
+    } else {
+      int pos = filename.lastIndexOf('.');
+      if (pos == -1) {
+        prefix = filename + "-";
+      } else {
+        prefix = filename.substring(0, pos) + "-";
+        suffix = filename.substring(pos);
+      }
+      // File.createTempFile requires the prefix to be at least three characters long
+      if (prefix.length() < 3)
+        prefix = "download-";
+    }
+
+    if (tempFolderPath == null)
+      return File.createTempFile(prefix, suffix);
+    else
+      return File.createTempFile(prefix, suffix, new File(tempFolderPath));
+  }
+
+  /**
+   * Invoke API by sending HTTP request with the given options.
+   *
+   * @param <T> Type
+   * @param path The sub-path of the HTTP URL
+   * @param method The request method, one of "GET", "POST", "PUT", "HEAD" and "DELETE"
+   * @param queryParams The query parameters
+   * @param body The request body object
+   * @param headerParams The header parameters
+   * @param formParams The form parameters
+   * @param accept The request's Accept header
+   * @param contentType The request's Content-Type header
+   * @param authNames The authentications to apply
+   * @param returnType The return type into which to deserialize the response
+   * @return The response body in type of string
+   * @throws ApiException API exception
+   */
+  public <T> ApiResponse<T> invokeAPI(String path, String method, List<Pair> queryParams, Object body, Map<String, String> headerParams, Map<String, Object> formParams, String accept, String contentType, String[] authNames, GenericType<T> returnType) throws ApiException {
+    updateParamsForAuth(authNames, queryParams, headerParams);
+
+    // Not using `.target(this.basePath).path(path)` below,
+    // to support (constant) query string in `path`, e.g. "/posts?draft=1"
+    WebTarget target = httpClient.target(this.basePath + path);
+
+    if (queryParams != null) {
+      for (Pair queryParam : queryParams) {
+        if (queryParam.getValue() != null) {
+          target = target.queryParam(queryParam.getName(), queryParam.getValue());
+        }
+      }
+    }
+
+    Invocation.Builder invocationBuilder = target.request().accept(accept);
+
+    for (Entry<String, String> entry : headerParams.entrySet()) {
+      String value = entry.getValue();
+      if (value != null) {
+        invocationBuilder = invocationBuilder.header(entry.getKey(), value);
+      }
+    }
+
+    for (Entry<String, String> entry : defaultHeaderMap.entrySet()) {
+      String key = entry.getKey();
+      if (!headerParams.containsKey(key)) {
+        String value = entry.getValue();
+        if (value != null) {
+          invocationBuilder = invocationBuilder.header(key, value);
+        }
+      }
+    }
+
+    Entity<?> entity = (body == null) ? Entity.json("") : serialize(body, formParams, contentType);
+
+    Response response = null;
+
+    try {
+      if ("GET".equals(method)) {
+        response = invocationBuilder.get();
+      } else if ("POST".equals(method)) {
+        response = invocationBuilder.post(entity);
+      } else if ("PUT".equals(method)) {
+        response = invocationBuilder.put(entity);
+      } else if ("DELETE".equals(method)) {
+        response = invocationBuilder.method("DELETE", entity);
+      } else if ("PATCH".equals(method)) {
+        response = invocationBuilder.method("PATCH", entity);
+      } else if ("HEAD".equals(method)) {
+        response = invocationBuilder.head();
+      } else if ("OPTIONS".equals(method)) {
+        response = invocationBuilder.options();
+      } else if ("TRACE".equals(method)) {
+        response = invocationBuilder.trace();
+      } else {
+        throw new ApiException(500, "unknown method type " + method);
+      }
+
+      int statusCode = response.getStatusInfo().getStatusCode();
+      Map<String, List<String>> responseHeaders = buildResponseHeaders(response);
+
+      if (response.getStatus() == Status.NO_CONTENT.getStatusCode()) {
+        return new ApiResponse<>(statusCode, responseHeaders);
+      } else if (response.getStatusInfo().getFamily() == Status.Family.SUCCESSFUL) {
+        if (returnType == null)
+          return new ApiResponse<>(statusCode, responseHeaders);
+        else
+          return new ApiResponse<>(statusCode, responseHeaders, deserialize(response, returnType));
+      } else {
+        String message = "error";
+        String respBody = null;
+        if (response.hasEntity()) {
+          try {
+            respBody = String.valueOf(response.readEntity(String.class));
+            message = respBody;
+          } catch (RuntimeException e) {
+            // e.printStackTrace();
+          }
+        }
+        throw new ApiException(
+          response.getStatus(),
+          message,
+          buildResponseHeaders(response),
+          respBody);
+      }
+    } finally {
+      try {
+        response.close();
+      } catch (Exception e) {
+        // it's not critical, since the response object is local in method invokeAPI; that's fine, just continue
+      }
+    }
+  }
+
+  /**
+   * Build the Client used to make HTTP requests.
+   * @param debugging Debug setting
+   * @return Client
+   */
+  protected Client buildHttpClient(boolean debugging) {
+    final ClientConfig clientConfig = new ClientConfig();
+    clientConfig.register(MultiPartFeature.class);
+    clientConfig.register(json);
+    clientConfig.register(JacksonFeature.class);
+    clientConfig.property(HttpUrlConnectorProvider.SET_METHOD_WORKAROUND, true);
+    // turn off compliance validation to be able to send payloads with DELETE calls
+    clientConfig.property(ClientProperties.SUPPRESS_HTTP_COMPLIANCE_VALIDATION, true);
+    if (debugging) {
+      clientConfig.register(new LoggingFeature(java.util.logging.Logger.getLogger(LoggingFeature.DEFAULT_LOGGER_NAME), java.util.logging.Level.INFO, LoggingFeature.Verbosity.PAYLOAD_ANY, 1024*50 /* Log payloads up to 50K */));
+      clientConfig.property(LoggingFeature.LOGGING_FEATURE_VERBOSITY, LoggingFeature.Verbosity.PAYLOAD_ANY);
+      // Set logger to ALL
+      java.util.logging.Logger.getLogger(LoggingFeature.DEFAULT_LOGGER_NAME).setLevel(java.util.logging.Level.ALL);
+    } else {
+      // suppress warnings for payloads with DELETE calls:
+      java.util.logging.Logger.getLogger("org.glassfish.jersey.client").setLevel(java.util.logging.Level.SEVERE);
+    }
+    performAdditionalClientConfiguration(clientConfig);
+    return ClientBuilder.newClient(clientConfig);
+  }
+
+  protected void performAdditionalClientConfiguration(ClientConfig clientConfig) {
+    // No-op extension point
+  }
+
+  protected Map<String, List<String>> buildResponseHeaders(Response response) {
+    Map<String, List<String>> responseHeaders = new HashMap<String, List<String>>();
+    for (Entry<String, List<Object>> entry: response.getHeaders().entrySet()) {
+      List<Object> values = entry.getValue();
+      List<String> headers = new ArrayList<String>();
+      for (Object o : values) {
+        headers.add(String.valueOf(o));
+      }
+      responseHeaders.put(entry.getKey(), headers);
+    }
+    return responseHeaders;
+  }
+
+  /**
+   * Update query and header parameters based on authentication settings.
+   *
+   * @param authNames The authentications to apply
+   * @param queryParams List of query parameters
+   * @param headerParams Map of header parameters
+   */
+  protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, Map<String, String> headerParams) {
+    for (String authName : authNames) {
+      Authentication auth = authentications.get(authName);
+      if (auth == null) throw new RuntimeException("Authentication undefined: " + authName);
+      auth.applyToParams(queryParams, headerParams);
+    }
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
new file mode 100644
index 000000000000..6c91e35f27a9
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
@@ -0,0 +1,91 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client;
+
+import java.util.Map;
+import java.util.List;
+
+
+public class ApiException extends Exception {
+    private int code = 0;
+    private Map<String, List<String>> responseHeaders = null;
+    private String responseBody = null;
+
+    public ApiException() {}
+
+    public ApiException(Throwable throwable) {
+        super(throwable);
+    }
+
+    public ApiException(String message) {
+        super(message);
+    }
+
+    public ApiException(String message, Throwable throwable, int code, Map<String, List<String>> responseHeaders, String responseBody) {
+        super(message, throwable);
+        this.code = code;
+        this.responseHeaders = responseHeaders;
+        this.responseBody = responseBody;
+    }
+
+    public ApiException(String message, int code, Map<String, List<String>> responseHeaders, String responseBody) {
+        this(message, (Throwable) null, code, responseHeaders, responseBody);
+    }
+
+    public ApiException(String message, Throwable throwable, int code, Map<String, List<String>> responseHeaders) {
+        this(message, throwable, code, responseHeaders, null);
+    }
+
+    public ApiException(int code, Map<String, List<String>> responseHeaders, String responseBody) {
+        this((String) null, (Throwable) null, code, responseHeaders, responseBody);
+    }
+
+    public ApiException(int code, String message) {
+        super(message);
+        this.code = code;
+    }
+
+    public ApiException(int code, String message, Map<String, List<String>> responseHeaders, String responseBody) {
+        this(code, message);
+        this.responseHeaders = responseHeaders;
+        this.responseBody = responseBody;
+    }
+
+    /**
+     * Get the HTTP status code.
+     *
+     * @return HTTP status code
+     */
+    public int getCode() {
+        return code;
+    }
+
+    /**
+     * Get the HTTP response headers.
+     *
+     * @return A map of list of string
+     */
+    public Map<String, List<String>> getResponseHeaders() {
+        return responseHeaders;
+    }
+
+    /**
+     * Get the HTTP response body.
+     *
+     * @return Response body in the form of string
+     */
+    public String getResponseBody() {
+        return responseBody;
+    }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiResponse.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiResponse.java
new file mode 100644
index 000000000000..4a3226d1dbb5
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiResponse.java
@@ -0,0 +1,59 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client;
+
+import java.util.List;
+import java.util.Map;
+
+/**
+ * API response returned by API call.
+ *
+ * @param <T> The type of data that is deserialized from response body
+ */
+public class ApiResponse<T> {
+    private final int statusCode;
+    private final Map<String, List<String>> headers;
+    private final T data;
+
+    /**
+     * @param statusCode The status code of HTTP response
+     * @param headers The headers of HTTP response
+     */
+    public ApiResponse(int statusCode, Map<String, List<String>> headers) {
+        this(statusCode, headers, null);
+    }
+
+    /**
+     * @param statusCode The status code of HTTP response
+     * @param headers The headers of HTTP response
+     * @param data The object deserialized from response bod
+     */
+    public ApiResponse(int statusCode, Map<String, List<String>> headers, T data) {
+        this.statusCode = statusCode;
+        this.headers = headers;
+        this.data = data;
+    }
+
+    public int getStatusCode() {
+        return statusCode;
+    }
+
+    public Map<String, List<String>> getHeaders() {
+        return headers;
+    }
+
+    public T getData() {
+        return data;
+    }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Configuration.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Configuration.java
new file mode 100644
index 000000000000..acbecda489dd
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Configuration.java
@@ -0,0 +1,39 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client;
+
+
+public class Configuration {
+    private static ApiClient defaultApiClient = new ApiClient();
+
+    /**
+     * Get the default API client, which would be used when creating API
+     * instances without providing an API client.
+     *
+     * @return Default API client
+     */
+    public static ApiClient getDefaultApiClient() {
+        return defaultApiClient;
+    }
+
+    /**
+     * Set the default API client, which would be used when creating API
+     * instances without providing an API client.
+     *
+     * @param apiClient API client
+     */
+    public static void setDefaultApiClient(ApiClient apiClient) {
+        defaultApiClient = apiClient;
+    }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/JSON.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/JSON.java
new file mode 100644
index 000000000000..e2d3f17b20a0
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/JSON.java
@@ -0,0 +1,42 @@
+package org.openapitools.client;
+
+import com.fasterxml.jackson.annotation.*;
+import com.fasterxml.jackson.databind.*;
+import org.openapitools.jackson.nullable.JsonNullableModule;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+
+import java.text.DateFormat;
+
+import javax.ws.rs.ext.ContextResolver;
+
+
+public class JSON implements ContextResolver<ObjectMapper> {
+  private ObjectMapper mapper;
+
+  public JSON() {
+    mapper = new ObjectMapper();
+    mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
+    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+    mapper.configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, false);
+    mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
+    mapper.enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING);
+    mapper.enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING);
+    mapper.setDateFormat(new RFC3339DateFormat());
+    mapper.registerModule(new JavaTimeModule());
+    JsonNullableModule jnm = new JsonNullableModule();
+    mapper.registerModule(jnm);
+  }
+
+  /**
+   * Set the date format for JSON (de)serialization with Date properties.
+   * @param dateFormat Date format
+   */
+  public void setDateFormat(DateFormat dateFormat) {
+    mapper.setDateFormat(dateFormat);
+  }
+
+  @Override
+  public ObjectMapper getContext(Class<?> type) {
+    return mapper;
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Pair.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Pair.java
new file mode 100644
index 000000000000..ae89aa614543
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/Pair.java
@@ -0,0 +1,61 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client;
+
+
+public class Pair {
+    private String name = "";
+    private String value = "";
+
+    public Pair (String name, String value) {
+        setName(name);
+        setValue(value);
+    }
+
+    private void setName(String name) {
+        if (!isValidString(name)) {
+            return;
+        }
+
+        this.name = name;
+    }
+
+    private void setValue(String value) {
+        if (!isValidString(value)) {
+            return;
+        }
+
+        this.value = value;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public String getValue() {
+        return this.value;
+    }
+
+    private boolean isValidString(String arg) {
+        if (arg == null) {
+            return false;
+        }
+
+        if (arg.trim().isEmpty()) {
+            return false;
+        }
+
+        return true;
+    }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/RFC3339DateFormat.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/RFC3339DateFormat.java
new file mode 100644
index 000000000000..9509fd089812
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/RFC3339DateFormat.java
@@ -0,0 +1,32 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+package org.openapitools.client;
+
+import com.fasterxml.jackson.databind.util.ISO8601DateFormat;
+import com.fasterxml.jackson.databind.util.ISO8601Utils;
+
+import java.text.FieldPosition;
+import java.util.Date;
+
+
+public class RFC3339DateFormat extends ISO8601DateFormat {
+
+  // Same as ISO8601DateFormat but serializing milliseconds.
+  @Override
+  public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) {
+    String value = ISO8601Utils.format(date, true);
+    toAppendTo.append(value);
+    return toAppendTo;
+  }
+
+}
\ No newline at end of file
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/StringUtil.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/StringUtil.java
new file mode 100644
index 000000000000..266c26be3a50
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/StringUtil.java
@@ -0,0 +1,61 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client;
+
+
+public class StringUtil {
+  /**
+   * Check if the given array contains the given value (with case-insensitive comparison).
+   *
+   * @param array The array
+   * @param value The value to search
+   * @return true if the array contains the value
+   */
+  public static boolean containsIgnoreCase(String[] array, String value) {
+    for (String str : array) {
+      if (value == null && str == null) {
+        return true;
+      }
+      if (value != null && value.equalsIgnoreCase(str)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Join an array of strings with the given separator.
+   * <p>
+   * Note: This might be replaced by utility method from commons-lang or guava someday
+   * if one of those libraries is added as dependency.
+   * </p>
+   *
+   * @param array     The array of strings
+   * @param separator The separator
+   * @return the resulting string
+   */
+  public static String join(String[] array, String separator) {
+    int len = array.length;
+    if (len == 0) {
+      return "";
+    }
+
+    StringBuilder out = new StringBuilder();
+    out.append(array[0]);
+    for (int i = 1; i < len; i++) {
+      out.append(separator).append(array[i]);
+    }
+    return out.toString();
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/ApiKeyAuth.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/ApiKeyAuth.java
new file mode 100644
index 000000000000..8d1d86ffc4c6
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/ApiKeyAuth.java
@@ -0,0 +1,75 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+import org.openapitools.client.Pair;
+
+import java.util.Map;
+import java.util.List;
+
+
+public class ApiKeyAuth implements Authentication {
+  private final String location;
+  private final String paramName;
+
+  private String apiKey;
+  private String apiKeyPrefix;
+
+  public ApiKeyAuth(String location, String paramName) {
+    this.location = location;
+    this.paramName = paramName;
+  }
+
+  public String getLocation() {
+    return location;
+  }
+
+  public String getParamName() {
+    return paramName;
+  }
+
+  public String getApiKey() {
+    return apiKey;
+  }
+
+  public void setApiKey(String apiKey) {
+    this.apiKey = apiKey;
+  }
+
+  public String getApiKeyPrefix() {
+    return apiKeyPrefix;
+  }
+
+  public void setApiKeyPrefix(String apiKeyPrefix) {
+    this.apiKeyPrefix = apiKeyPrefix;
+  }
+
+  @Override
+  public void applyToParams(List<Pair> queryParams, Map<String, String> headerParams) {
+    if (apiKey == null) {
+      return;
+    }
+    String value;
+    if (apiKeyPrefix != null) {
+      value = apiKeyPrefix + " " + apiKey;
+    } else {
+      value = apiKey;
+    }
+    if ("query".equals(location)) {
+      queryParams.add(new Pair(paramName, value));
+    } else if ("header".equals(location)) {
+      headerParams.put(paramName, value);
+    }
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/Authentication.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/Authentication.java
new file mode 100644
index 000000000000..ae096bbc69c2
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/Authentication.java
@@ -0,0 +1,29 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+import org.openapitools.client.Pair;
+
+import java.util.Map;
+import java.util.List;
+
+public interface Authentication {
+    /**
+     * Apply authentication settings to header and query params.
+     *
+     * @param queryParams List of query parameters
+     * @param headerParams Map of header parameters
+     */
+    void applyToParams(List<Pair> queryParams, Map<String, String> headerParams);
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBasicAuth.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBasicAuth.java
new file mode 100644
index 000000000000..f4671cb922da
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBasicAuth.java
@@ -0,0 +1,54 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+import org.openapitools.client.Pair;
+
+import java.util.Base64;
+import java.nio.charset.StandardCharsets;
+
+import java.util.Map;
+import java.util.List;
+
+
+
+public class HttpBasicAuth implements Authentication {
+  private String username;
+  private String password;
+
+  public String getUsername() {
+    return username;
+  }
+
+  public void setUsername(String username) {
+    this.username = username;
+  }
+
+  public String getPassword() {
+    return password;
+  }
+
+  public void setPassword(String password) {
+    this.password = password;
+  }
+
+  @Override
+  public void applyToParams(List<Pair> queryParams, Map<String, String> headerParams) {
+    if (username == null && password == null) {
+      return;
+    }
+    String str = (username == null ? "" : username) + ":" + (password == null ? "" : password);
+    headerParams.put("Authorization", "Basic " + Base64.getEncoder().encodeToString(str.getBytes(StandardCharsets.UTF_8)));
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBearerAuth.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBearerAuth.java
new file mode 100644
index 000000000000..9fb739f7d087
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/HttpBearerAuth.java
@@ -0,0 +1,60 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+import org.openapitools.client.Pair;
+
+import java.util.Map;
+import java.util.List;
+
+
+public class HttpBearerAuth implements Authentication {
+  private final String scheme;
+  private String bearerToken;
+
+  public HttpBearerAuth(String scheme) {
+    this.scheme = scheme;
+  }
+
+  /**
+   * Gets the token, which together with the scheme, will be sent as the value of the Authorization header.
+   *
+   * @return The bearer token
+   */
+  public String getBearerToken() {
+    return bearerToken;
+  }
+
+  /**
+   * Sets the token, which together with the scheme, will be sent as the value of the Authorization header.
+   *
+   * @param bearerToken The bearer token to send in the Authorization header
+   */
+  public void setBearerToken(String bearerToken) {
+    this.bearerToken = bearerToken;
+  }
+
+  @Override
+  public void applyToParams(List<Pair> queryParams, Map<String, String> headerParams) {
+    if(bearerToken == null) {
+      return;
+    }
+
+    headerParams.put("Authorization", (scheme != null ? upperCaseBearer(scheme) + " " : "") + bearerToken);
+  }
+
+  private static String upperCaseBearer(String scheme) {
+    return ("bearer".equalsIgnoreCase(scheme)) ? "Bearer" : scheme;
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuth.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuth.java
new file mode 100644
index 000000000000..5f33142af35c
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuth.java
@@ -0,0 +1,39 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+import org.openapitools.client.Pair;
+
+import java.util.Map;
+import java.util.List;
+
+
+public class OAuth implements Authentication {
+  private String accessToken;
+
+  public String getAccessToken() {
+    return accessToken;
+  }
+
+  public void setAccessToken(String accessToken) {
+    this.accessToken = accessToken;
+  }
+
+  @Override
+  public void applyToParams(List<Pair> queryParams, Map<String, String> headerParams) {
+    if (accessToken != null) {
+      headerParams.put("Authorization", "Bearer " + accessToken);
+    }
+  }
+}
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuthFlow.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuthFlow.java
new file mode 100644
index 000000000000..b2d11ff0c4f0
--- /dev/null
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/auth/OAuthFlow.java
@@ -0,0 +1,18 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.auth;
+
+public enum OAuthFlow {
+    accessCode, implicit, password, application
+}