Add base argument class for conditionally reading objects.

api/src/main/java/io/minio/BaseArgs.java

@@ -19,6 +19,7 @@
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
+import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;
 import java.util.List;
@@ -119,24 +120,34 @@ public B extraQueryParams(Map<String, String> queryParams) {
       return (B) this;
     }
 
-    /** Creates derived Args class with each attribute populated. */
     @SuppressWarnings("unchecked") // safe as B will always be the builder of the current args class
-    public A build() throws IllegalArgumentException {
+    private A newInstance() {
       try {
-        A args = (A) this.getClass().getEnclosingClass().getDeclaredConstructor().newInstance();
-        operations.forEach(operation -> operation.accept(args));
-        validate(args);
-        return args;
+        for (Constructor<?> constructor :
+            this.getClass().getEnclosingClass().getDeclaredConstructors()) {
+          if (constructor.getParameterCount() == 0) {
+            return (A) constructor.newInstance();
+          }
+        }
+
+        throw new RuntimeException(
+            this.getClass().getEnclosingClass() + " must have no argument constructor");
       } catch (InstantiationException
           | IllegalAccessException
           | InvocationTargetException
-          | NoSuchMethodException
           | SecurityException e) {
-        // This should never happen as we'll always have the
-        // Builder class as an enclosed class of the args class
-        e.printStackTrace();
-        return null;
+        // Args class must have no argument constructor with at least protected access.
+        throw new RuntimeException(e);
       }
     }
+
+    /** Creates derived Args class with each attribute populated. */
+    @SuppressWarnings("unchecked") // safe as B will always be the builder of the current args class
+    public A build() throws IllegalArgumentException {
+      A args = newInstance();
+      operations.forEach(operation -> operation.accept(args));
+      validate(args);
+      return args;
+    }
   }
 }

api/src/main/java/io/minio/ComposeObjectArgs.java

@@ -16,11 +16,31 @@
 
 package io.minio;
 
+import java.util.LinkedList;
 import java.util.List;
+import okhttp3.HttpUrl;
 
 public class ComposeObjectArgs extends ObjectWriteArgs {
   List<ComposeSource> sources;
 
+  protected ComposeObjectArgs() {}
+
+  public ComposeObjectArgs(CopyObjectArgs args) {
+    this.extraHeaders = args.extraHeaders;
+    this.extraQueryParams = args.extraQueryParams;
+    this.bucketName = args.bucketName;
+    this.region = args.region;
+    this.objectName = args.objectName;
+    this.headers = args.headers;
+    this.userMetadata = args.userMetadata;
+    this.sse = args.sse;
+    this.tags = args.tags;
+    this.retention = args.retention;
+    this.legalHold = args.legalHold;
+    this.sources = new LinkedList<>();
+    this.sources.add(new ComposeSource(args.source()));
+  }
+
   public List<ComposeSource> sources() {
     return sources;
   }
@@ -29,7 +49,21 @@ public static Builder builder() {
     return new Builder();
   }
 
+  @Override
+  public void validateSse(HttpUrl url) {
+    super.validateSse(url);
+    for (ComposeSource source : sources) {
+      source.validateSsec(url);
+    }
+  }
+
   public static final class Builder extends ObjectWriteArgs.Builder<Builder, ComposeObjectArgs> {
+    private void validateSources(List<ComposeSource> sources) {
+      if (sources == null || sources.isEmpty()) {
+        throw new IllegalArgumentException("compose sources cannot be empty");
+      }
+    }
+
     @Override
     protected void validate(ComposeObjectArgs args) {
       super.validate(args);
@@ -41,11 +75,5 @@ public Builder sources(List<ComposeSource> sources) {
       operations.add(args -> args.sources = sources);
       return this;
     }
-
-    private void validateSources(List<ComposeSource> sources) {
-      if (sources == null || sources.isEmpty()) {
-        throw new IllegalArgumentException("compose sources cannot be empty");
-      }
-    }
   }
 }

api/src/main/java/io/minio/ComposeSource.java

@@ -20,84 +20,78 @@
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
-import java.time.ZonedDateTime;
-import okhttp3.HttpUrl;
-
-/** Source information to compose object. */
-public class ComposeSource extends ObjectVersionArgs {
-  private Long offset;
-  private Long length;
-  private long objectSize;
-  private String matchETag;
-  private String notMatchETag;
-  private ZonedDateTime modifiedSince;
-  private ZonedDateTime unmodifiedSince;
-  private ServerSideEncryptionCustomerKey ssec;
-
-  private Multimap<String, String> headers;
-
-  public Long offset() {
-    return offset;
+import io.minio.errors.InternalException;
+
+/** A source object defintion for {@link ComposeObjectArgs}. */
+public class ComposeSource extends ObjectConditionalReadArgs {
+  private Long objectSize = null;
+  private Multimap<String, String> headers = null;
+
+  protected ComposeSource() {}
+
+  public ComposeSource(ObjectConditionalReadArgs args) {
+    this.extraHeaders = args.extraHeaders;
+    this.extraQueryParams = args.extraQueryParams;
+    this.bucketName = args.bucketName;
+    this.region = args.region;
+    this.objectName = args.objectName;
+    this.versionId = args.versionId;
+    this.ssec = args.ssec;
+    this.offset = args.offset;
+    this.length = args.length;
+    this.matchETag = args.matchETag;
+    this.notMatchETag = args.notMatchETag;
+    this.modifiedSince = args.modifiedSince;
+    this.unmodifiedSince = args.unmodifiedSince;
   }
 
-  public Long length() {
-    return length;
-  }
-
-  public long objectSize() {
-    return objectSize;
-  }
-
-  public String matchETag() {
-    return matchETag;
-  }
-
-  public String notMatchETag() {
-    return notMatchETag;
-  }
+  private void throwException(long objectsize, long arg, String argName) {
+    StringBuilder builder =
+        new StringBuilder().append("source ").append(bucketName).append("/").append(objectName);
 
-  public ZonedDateTime modifiedSince() {
-    return modifiedSince;
-  }
+    if (versionId != null) {
+      builder.append("?versionId=").append(versionId);
+    }
 
-  public ZonedDateTime unmodifiedSince() {
-    return unmodifiedSince;
-  }
+    builder
+        .append(": ")
+        .append(argName)
+        .append(" ")
+        .append(arg)
+        .append(" is beyond object size ")
+        .append(objectSize);
 
-  public Multimap<String, String> headers() {
-    return headers;
+    throw new IllegalArgumentException(builder.toString());
   }
 
-  public ServerSideEncryptionCustomerKey ssec() {
-    return ssec;
-  }
+  private void validateSize(long objectSize) {
+    if (offset != null && offset >= objectSize) {
+      throwException(objectSize, offset, "offset");
+    }
 
-  public void validateSse(HttpUrl url) {
-    checkSse(ssec, url);
-  }
+    if (length != null) {
+      if (length > objectSize) {
+        throwException(objectSize, length, "length");
+      }
 
-  public static Builder builder() {
-    return new Builder();
+      if (offset + length > objectSize) {
+        throwException(objectSize, offset + length, "compose size");
+      }
+    }
   }
 
-  /** Constructs header. */
-  public void buildHeaders(long objectSize, String etag) throws IllegalArgumentException {
+  public void buildHeaders(long objectSize, String etag) {
     validateSize(objectSize);
-    Multimap<String, String> headers = HashMultimap.create();
-    headers.put("x-amz-copy-source", S3Escaper.encodePath(bucketName + "/" + objectName));
-    headers.put("x-amz-copy-source-if-match", etag);
-
-    if (extraHeaders() != null) {
-      headers.putAll(extraHeaders());
-    }
+    this.objectSize = Long.valueOf(objectSize);
 
-    if (matchETag != null) {
-      headers.put("x-amz-copy-source-if-match", matchETag);
+    String copySource = S3Escaper.encodePath(bucketName + "/" + objectName);
+    if (versionId != null) {
+      copySource += "?versionId=" + S3Escaper.encode(versionId);
     }
 
-    if (ssec != null) {
-      headers.putAll(Multimaps.forMap(ssec.copySourceHeaders()));
-    }
+    Multimap<String, String> headers = HashMultimap.create();
+    headers.put("x-amz-copy-source", copySource);
+    headers.put("x-amz-copy-source-if-match", (matchETag != null) ? matchETag : etag);
 
     if (notMatchETag != null) {
       headers.put("x-amz-copy-source-if-none-match", notMatchETag);
@@ -115,90 +109,36 @@ public void buildHeaders(long objectSize, String etag) throws IllegalArgumentExc
           unmodifiedSince.format(Time.HTTP_HEADER_DATE_FORMAT));
     }
 
-    this.objectSize = objectSize;
-    this.headers = headers;
-  }
-
-  private void validateSize(long objectSize) throws IllegalArgumentException {
-    if (offset != null && offset >= objectSize) {
-      throw new IllegalArgumentException(
-          "source "
-              + bucketName
-              + "/"
-              + objectName
-              + ": offset "
-              + offset
-              + " is beyond object size "
-              + objectSize);
+    if (ssec != null) {
+      headers.putAll(Multimaps.forMap(ssec.copySourceHeaders()));
     }
 
-    if (length != null) {
-      if (length > objectSize) {
-        throw new IllegalArgumentException(
-            "source "
-                + bucketName
-                + "/"
-                + objectName
-                + ": length "
-                + length
-                + " is beyond object size "
-                + objectSize);
-      }
-
-      if (offset + length > objectSize) {
-        throw new IllegalArgumentException(
-            "source "
-                + bucketName
-                + "/"
-                + objectName
-                + ": compose size "
-                + (offset + length)
-                + " is beyond object size "
-                + objectSize);
-      }
-    }
+    this.headers = Multimaps.unmodifiableMultimap(headers);
   }
 
-  /** Argument builder of {@link ComposeSource}. */
-  public static final class Builder extends ObjectVersionArgs.Builder<Builder, ComposeSource> {
-
-    public Builder offset(long offset) {
-      validateNullOrPositive(offset, "offset");
-      operations.add(args -> args.offset = offset);
-      return this;
-    }
-
-    public Builder length(long length) {
-      validateNullOrPositive(length, "length");
-      operations.add(args -> args.length = length);
-      return this;
+  public long objectSize() throws InternalException {
+    if (this.objectSize == null) {
+      throw new InternalException(
+          "buildHeaders(long objectSize, String etag) must be called prior to this method invocation");
     }
 
-    public Builder ssec(ServerSideEncryptionCustomerKey ssec) {
-      operations.add(args -> args.ssec = ssec);
-      return this;
-    }
-
-    public Builder matchETag(String etag) {
-      validateNullOrNotEmptyString(etag, "etag");
-      operations.add(args -> args.matchETag = etag);
-      return this;
-    }
+    return this.objectSize;
+  }
 
-    public Builder notMatchETag(String etag) {
-      validateNullOrNotEmptyString(etag, "etag");
-      operations.add(args -> args.notMatchETag = etag);
-      return this;
+  public Multimap<String, String> headers() throws InternalException {
+    if (this.headers == null) {
+      throw new InternalException(
+          "buildHeaders(long objectSize, String etag) must be called prior to this method invocation");
     }
 
-    public Builder modifiedSince(ZonedDateTime modifiedTime) {
-      operations.add(args -> args.modifiedSince = modifiedTime);
-      return this;
-    }
+    return this.headers;
+  }
 
-    public Builder unmodifiedSince(ZonedDateTime unmodifiedTime) {
-      operations.add(args -> args.unmodifiedSince = unmodifiedTime);
-      return this;
-    }
+  public static Builder builder() {
+    return new Builder();
   }
+
+  /** Argument builder of {@link ComposeSource}. */
+  public static final class Builder
+      extends ObjectConditionalReadArgs.Builder<Builder, ComposeSource> {}
 }