Rename old LocalvariablesNamesEnhancerJava7, which also generates par…

…ameter names fields. This class can be dropped when we drop Java 7 support. Plain LocalvariablesNamesEnhancer will not do it anymore, because parameter names are available using standard API in Java 8. Build of Play now requires Java 8, but will still run with Java 7.
playframework · Jan 10, 2017 · 812412f · 812412f
1 parent dc44c0a
commit 812412f
Show file tree

Hide file tree

Showing 5 changed files with 260 additions and 130 deletions.
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,7 @@
 sudo: required
 language: java
 jdk:
-  - openjdk7 
+  - oraclejdk8
 #before_install:
 #  - cat /etc/hosts # optionally check the content *before*
 #  - sudo hostname "$(hostname | cut -c1-63)"

diff --git a/framework/src/play/CorePlugin.java b/framework/src/play/CorePlugin.java
@@ -291,7 +291,7 @@ protected Enhancer[] defaultEnhancers() {
             new SigEnhancer(),
             new ControllersEnhancer(),
             new MailerEnhancer(),
-            new LocalvariablesNamesEnhancer()
+            Play.classes.java8 ? new LocalvariablesNamesEnhancer() : new LocalvariablesNamesEnhancerJava7()
         };
     }
 

diff --git a/framework/src/play/classloading/enhancers/LocalvariablesNamesEnhancer.java b/framework/src/play/classloading/enhancers/LocalvariablesNamesEnhancer.java
@@ -1,10 +1,10 @@
 package play.classloading.enhancers;
 
-import javassist.*;
+import javassist.CtClass;
+import javassist.CtMethod;
 import javassist.bytecode.*;
 import play.Logger;
 import play.classloading.ApplicationClasses.ApplicationClass;
-import play.libs.F.T2;
 
 import java.lang.reflect.Field;
 import java.util.*;
@@ -16,7 +16,7 @@ public class LocalvariablesNamesEnhancer extends Enhancer {
 
     @Override
     public void enhanceThisClass(ApplicationClass applicationClass) throws Exception {
-        if (isAnon(applicationClass)) {
+        if (isAnon(applicationClass) || isScala(applicationClass)) {
             return;
         }
 
@@ -37,72 +37,9 @@ public void enhanceThisClass(ApplicationClass applicationClass) throws Exception
             if (codeAttribute == null || javassist.Modifier.isAbstract(method.getModifiers())) {
                 continue;
             }
+
             LocalVariableAttribute localVariableAttribute = (LocalVariableAttribute) codeAttribute.getAttribute("LocalVariableTable");
-            List<T2<Integer,String>> parameterNames = new ArrayList<>();
-
             if (localVariableAttribute == null) {
-                if(method.getParameterTypes().length > 0)
-                    continue;
-            } else {
-                if(localVariableAttribute.tableLength() < method.getParameterTypes().length + (Modifier.isStatic(method.getModifiers()) ? 0 : 1)) {
-                    Logger.warn("weird: skipping method %s %s as its number of local variables is incorrect (lv=%s || lv.length=%s || params.length=%s || (isStatic? %s)", method.getReturnType().getName(), method.getLongName(), localVariableAttribute, localVariableAttribute != null ? localVariableAttribute.tableLength() : -1, method.getParameterTypes().length, Modifier.isStatic(method.getModifiers()));
-                }
-                for(int i=0; i<localVariableAttribute.tableLength(); i++) {
-                    if (!"__stackRecorder".equals(localVariableAttribute.variableName(i))) {
-                        parameterNames.add(new T2<>(localVariableAttribute.startPc(i) + localVariableAttribute.index(i), localVariableAttribute.variableName(i)));
-                    }
-                }
-                Collections.sort(parameterNames, new Comparator<T2<Integer,String>>() {
-                    @Override
-                    public int compare(T2<Integer, String> o1, T2<Integer, String> o2) {
-                        return o1._1.compareTo(o2._1);
-                    }
-
-                });
-            }
-            List<String> names = new ArrayList<>();
-            for (int i = 0; i < method.getParameterTypes().length + (Modifier.isStatic(method.getModifiers()) ? 0 : 1); i++) {
-                if (localVariableAttribute == null) {
-                    continue;
-                }
-                try {
-                    String name = parameterNames.get(i)._2;
-                    if (!"this".equals(name)) {
-                        names.add(name);
-                    }
-                } catch (Exception e) {
-                    Logger.warn(e, "While applying localvariables to %s.%s, param %s", ctClass.getName(), method.getName(), i);
-                }
-            }
-            StringBuilder iv = new StringBuilder();
-            if (names.isEmpty()) {
-                iv.append("new String[0];");
-            } else {
-                iv.append("new String[] {");
-                for (Iterator<String> i = names.iterator(); i.hasNext();) {
-                    iv.append("\"");
-                    String aliasedName = i.next();
-                    if (aliasedName.contains("$")) {
-                        aliasedName = aliasedName.substring(0, aliasedName.indexOf("$"));
-                    }
-                    iv.append(aliasedName);
-                    iv.append("\"");
-                    if (i.hasNext()) {
-                        iv.append(",");
-                    }
-                }
-                iv.append("};");
-            }
-
-            String sigField = "$" + method.getName() + LocalVariablesNamesTracer.computeMethodHash(method.getParameterTypes());
-            try { // #1198
-                ctClass.getDeclaredField(sigField);
-            } catch (NotFoundException nfe) {
-                CtField signature = CtField.make("public static String[] " + sigField + " = " + iv, ctClass);
-                ctClass.addField(signature);
-            }
-
-            if (localVariableAttribute == null || isScala(applicationClass)) {
                 continue;
             }
 
@@ -122,18 +59,11 @@ public int compare(T2<Integer, String> o1, T2<Integer, String> o2) {
                     aliasedName = aliasedName.substring(0, aliasedName.indexOf("$"));
                 }
 
-
                 if ("this".equals(name)) {
                     continue;
                 }
 
-                /* DEBUG
-                IO.write(ctClass.toBytecode(), new File("/tmp/lv_"+applicationClass.name+".class"));
-                ctClass.defrost();
-                 */
-
                 try {
-
                     // The instruction at which this local variable has been created
                     Integer pc = localVariableAttribute.startPc(i);
 
@@ -191,7 +121,7 @@ public int compare(T2<Integer, String> o1, T2<Integer, String> o2) {
 
     }
 
-    private static Bytecode makeBytecodeForLVStore(CtMethod method, String sig, String name, int slot) {
+    static Bytecode makeBytecodeForLVStore(CtMethod method, String sig, String name, int slot) {
         Bytecode b = new Bytecode(method.getMethodInfo().getConstPool());
         b.addLdc(name);
         if("I".equals(sig) || "B".equals(sig) || "C".equals(sig) || "S".equals(sig) || "Z".equals(sig))
@@ -228,49 +158,6 @@ public interface LocalVariablesSupport {
      */
     public static class LocalVariablesNamesTracer {
 
-        public static Integer computeMethodHash(CtClass[] parameters) {
-            String[] names = new String[parameters.length];
-            for (int i = 0; i < parameters.length; i++) {
-                names[i] = parameters[i].getName();
-            }
-            return computeMethodHash(names);
-        }
-
-        public static Integer computeMethodHash(Class<?>[] parameters) {
-            String[] names = new String[parameters.length];
-            for (int i = 0; i < parameters.length; i++) {
-                Class<?> param = parameters[i];
-                names[i] = "";
-                if (param.isArray()) {
-                    int level = 1;
-                    param = param.getComponentType();
-                    // Array of array
-                    while (param.isArray()) {
-                        level++;
-                        param = param.getComponentType();
-                    }
-                    names[i] = param.getName();
-                    for (int j = 0; j < level; j++) {
-                        names[i] += "[]";
-                    }
-                } else {
-                    names[i] = param.getName();
-                }
-            }
-            return computeMethodHash(names);
-        }
-
-        public static Integer computeMethodHash(String[] parameters) {
-            StringBuilder buffer = new StringBuilder();
-            for (String param : parameters) {
-                buffer.append(param);
-            }
-            Integer hash = buffer.toString().hashCode();
-            if (hash < 0) {
-                return -hash;
-            }
-            return hash;
-        }
         static final ThreadLocal<Stack<Map<String, Object>>> localVariables = new ThreadLocal<>();
 
         public static void checkEmpty() {
@@ -378,9 +265,9 @@ public static void setLocalVariablesStateAfterAwait(Stack<Map<String, Object>> s
         }
     }
 
-    private static final Map<Integer, Integer> storeByCode = new HashMap<>();
+    static final Map<Integer, Integer> storeByCode = new HashMap<>();
 
-    /**
+    /*
      * Useful instructions
      */
     static {