local variables were made available in the source text passed

to insertBefore() etc.


git-svn-id: http://anonsvn.jboss.org/repos/javassist/trunk@68 30ef5769-5b8d-40dd-aea6-55b5d6557bb3

Readme.html

@@ -253,6 +253,8 @@ see javassist.Dump.
 <p>- version 2.7
 
 <ul>
+  <li>Now local variables were made available in the source text passed to
+  CtBehavior.insertBefore(), MethodCall.replace(), etc.
   <li>CtClass.main(), which prints the version number, has been added.
   <li>ClassPool.SimpleLoader has been public.
   <li>javassist.bytecode.DeprecatedAttribute has been added.

src/main/javassist/CtBehavior.java

@@ -352,8 +352,9 @@ public abstract class CtBehavior extends CtMember {
         CodeIterator iterator = ca.iterator();
         Javac jv = new Javac(declaringClass);
         try {
-            jv.recordParams(getParameterTypes(),
-                            Modifier.isStatic(getModifiers()));
+            int nvars = jv.recordParams(getParameterTypes(),
+                                        Modifier.isStatic(getModifiers()));
+            jv.recordParamNames(ca, nvars);
             jv.compileStmnt(src);
             Bytecode b = jv.getBytecode();
             int stack = b.getMaxStack();
@@ -418,8 +419,9 @@ public abstract class CtBehavior extends CtMember {
         b.setStackDepth(ca.getMaxStack() + 1);
         Javac jv = new Javac(b, declaringClass);
         try {
-            jv.recordParams(getParameterTypes(),
-                            Modifier.isStatic(getModifiers()));
+            int nvars = jv.recordParams(getParameterTypes(),
+                                        Modifier.isStatic(getModifiers()));
+            jv.recordParamNames(ca, nvars);
             CtClass rtype = getReturnType0();
             int varNo = jv.recordReturnType(rtype, true);
 
@@ -750,6 +752,7 @@ public abstract class CtBehavior extends CtMember {
         CodeIterator iterator = ca.iterator();
         Javac jv = new Javac(declaringClass);
         try {
+            jv.recordLocalVariables(ca, index);
             jv.recordParams(getParameterTypes(),
                             Modifier.isStatic(getModifiers()));
             jv.compileStmnt(src);

src/main/javassist/CtClass.java

@@ -36,7 +36,7 @@ public abstract class CtClass {
     /**
      * The version number of this release.
      */
-    public static final String version = "2.7 alpha 7";
+    public static final String version = "2.7 alpha 8";
 
     /**
      * Prints the version number and the copyright notice.

src/main/javassist/compiler/Javac.java

@@ -25,6 +25,8 @@ import javassist.CtConstructor;
 import javassist.CannotCompileException;
 import javassist.Modifier;
 import javassist.bytecode.Bytecode;
+import javassist.bytecode.CodeAttribute;
+import javassist.bytecode.LocalVariableAttribute;
 import javassist.bytecode.Opcode;
 import javassist.NotFoundException;
 
@@ -241,6 +243,66 @@ public class Javac {
         b.addOpcode(op);
     }
 
+    /**
+     * Records local variables available at the specified program counter.
+     * If the LocalVariableAttribute is not available, this method does not
+     * record any local variable.  It only returns false.
+     *
+     * @param pc    program counter (>= 0)
+     * @return false if the CodeAttribute does not include a
+     *              LocalVariableAttribute.
+     */
+    public boolean recordLocalVariables(CodeAttribute ca, int pc)
+        throws CompileError
+    {
+        LocalVariableAttribute va
+            = (LocalVariableAttribute)
+              ca.getAttribute(LocalVariableAttribute.tag);
+        if (va == null)
+            return false;
+
+        int n = va.tableLength();
+        for (int i = 0; i < n; ++i) {
+            int start = va.startPc(i);
+            int len = va.codeLength(i);
+            if (start <= pc && pc < start + len)
+                gen.recordVariable(va.descriptor(i), va.variableName(i),
+                                   va.index(i), stable);
+        }
+
+        return true;
+    }
+
+    /**
+     * Records parameter names if the LocalVariableAttribute is available.
+     * It returns false unless the LocalVariableAttribute is available.
+     *
+     * @param numOfLocalVars    the number of local variables used
+     *                          for storing the parameters.
+     * @return false if the CodeAttribute does not include a
+     *              LocalVariableAttribute.
+     */
+    public boolean recordParamNames(CodeAttribute ca, int numOfLocalVars)
+        throws CompileError
+    {
+        LocalVariableAttribute va
+            = (LocalVariableAttribute)
+              ca.getAttribute(LocalVariableAttribute.tag);
+        if (va == null)
+            return false;
+
+        int n = va.tableLength();
+        for (int i = 0; i < n; ++i) {
+            int index = va.index(i);
+            if (index < numOfLocalVars)
+                gen.recordVariable(va.descriptor(i), va.variableName(i),
+                                   index, stable);
+        }
+
+        return true;
+    }
+
+
     /**
      * Makes variables $0 (this), $1, $2, ..., and $args represent method
      * parameters.  $args represents an array of all the parameters.
@@ -250,10 +312,10 @@ public class Javac {
      * <code>compileExpr()</code>.  The correct value of
      * <code>isStatic</code> must be recorded before compilation.
      */
-    public void recordParams(CtClass[] params, boolean isStatic)
+    public int recordParams(CtClass[] params, boolean isStatic)
         throws CompileError
     {
-        gen.recordParams(params, isStatic, "$", "$args", "$$", stable);
+        return gen.recordParams(params, isStatic, "$", "$args", "$$", stable);
     }
 
     /**
@@ -273,12 +335,12 @@ public class Javac {
      * @param isStatic  true if the method in which the compiled bytecode
      *                  is embedded is static.
      */
-    public void recordParams(String target, CtClass[] params,
+    public int recordParams(String target, CtClass[] params,
                              boolean use0, int varNo, boolean isStatic)
         throws CompileError
     {
-        gen.recordParams(params, isStatic, "$", "$args", "$$",
-                         use0, varNo, target, stable);
+        return gen.recordParams(params, isStatic, "$", "$args", "$$",
+                                use0, varNo, target, stable);
     }
 
     /**

src/main/javassist/compiler/JvstCodeGen.java

@@ -462,13 +462,13 @@ public class JvstCodeGen extends MemberCodeGen {
      * $0 is equivalent to THIS if the method is not static.  Otherwise,
      * if the method is static, then $0 is not available.
      */
-    public void recordParams(CtClass[] params, boolean isStatic,
+    public int recordParams(CtClass[] params, boolean isStatic,
                              String prefix, String paramVarName,
                              String paramsName, SymbolTable tbl)
         throws CompileError
     {
-        recordParams(params, isStatic, prefix, paramVarName,
-                     paramsName, !isStatic, 0, getThisName(), tbl);
+        return recordParams(params, isStatic, prefix, paramVarName,
+                            paramsName, !isStatic, 0, getThisName(), tbl);
     }
 
     /**
@@ -484,11 +484,11 @@ public class JvstCodeGen extends MemberCodeGen {
      * @param isStatic  true if the method in which the compiled bytecode
      *                  is embedded is static.
      */
-    public void recordParams(CtClass[] params, boolean isStatic,
-                             String prefix, String paramVarName,
-                             String paramsName, boolean use0,
-                             int paramBase, String target,
-                             SymbolTable tbl)
+    public int recordParams(CtClass[] params, boolean isStatic,
+                            String prefix, String paramVarName,
+                            String paramsName, boolean use0,
+                            int paramBase, String target,
+                            SymbolTable tbl)
         throws CompileError
     {
         int varNo;
@@ -516,6 +516,8 @@ public class JvstCodeGen extends MemberCodeGen {
 
         if (getMaxLocals() < varNo)
             setMaxLocals(varNo);
+
+        return varNo;
     }
 
     /**
@@ -574,9 +576,9 @@ public class JvstCodeGen extends MemberCodeGen {
         String cname = null;
         if (type == CLASS) {
             if (dim == 0)
-                cname = typeDesc;
+                cname = typeDesc.substring(1, typeDesc.length() - 1);
             else
-                cname = typeDesc.substring(dim);
+                cname = typeDesc.substring(dim + 1, typeDesc.length() - 1);
         }
 
         Declarator decl

src/main/javassist/expr/Cast.java

@@ -112,6 +112,7 @@ public class Cast extends Expr {
 
             Bytecode bytecode = jc.getBytecode();
             storeStack(params, true, paramVar, bytecode);
+            jc.recordLocalVariables(ca, pos);
             jc.compileStmnt(statement);
             bytecode.addLoad(retVar, retType);
 

src/main/javassist/expr/FieldAccess.java

@@ -188,6 +188,7 @@ public class FieldAccess extends Expr {
 
             Bytecode bytecode = jc.getBytecode();
             storeStack(params, isStatic(), paramVar, bytecode);
+            jc.recordLocalVariables(ca, pos);
             jc.compileStmnt(statement);
             if (read)
                 bytecode.addLoad(retVar, retType);

src/main/javassist/expr/Instanceof.java

@@ -117,6 +117,7 @@ public class Instanceof extends Expr {
 
             Bytecode bytecode = jc.getBytecode();
             storeStack(params, true, paramVar, bytecode);
+            jc.recordLocalVariables(ca, pos);
             jc.compileStmnt(statement);
             bytecode.addLoad(retVar, retType);
 

src/main/javassist/expr/MethodCall.java

@@ -210,6 +210,7 @@ public class MethodCall extends Expr {
 
             Bytecode bytecode = jc.getBytecode();
             storeStack(params, c == INVOKESTATIC, paramVar, bytecode);
+            jc.recordLocalVariables(ca, pos);
             jc.compileStmnt(statement);
             if (retType != CtClass.voidType)
                 bytecode.addLoad(retVar, retType);

src/main/javassist/expr/NewExpr.java

@@ -177,6 +177,7 @@ public class NewExpr extends Expr {
 
             Bytecode bytecode = jc.getBytecode();
             storeStack(params, true, paramVar, bytecode);
+            jc.recordLocalVariables(ca, pos);
             jc.compileStmnt(statement);
             bytecode.addAload(retVar);
 

tutorial/tutorial.html

@@ -690,6 +690,6 @@ binary code license.</i>
 
 <hr>
 Java(TM) is a trademark of Sun Microsystems, Inc.<br>
-Copyright (C) 2000-2003 by Shigeru Chiba, All rights reserved.
+Copyright (C) 2000-2004 by Shigeru Chiba, All rights reserved.
 </body>
 </html>

tutorial/tutorial2.html

@@ -149,12 +149,20 @@ if (i < 0) { i = -i; }
 </pre></ul>
 
 <p>The statement and the block can refer to fields and methods.
-However, they <em>cannot refer to local variables</em> declared in the
-method that they are inserted into.
-They can refer to the parameters
-to the method although they must use different names
-<code>$0</code>, <code>$1</code>, <code>$2</code>, ... described
-below.  Declaring a local variable in the block is allowed.
+They can also refer to the parameters
+to the method that they are inserted into
+if that method was compiled with the -g option
+(to include a local variable attribute in the class file).
+Otherwise, they must access the method parameters through the special
+variables <code>$0</code>, <code>$1</code>, <code>$2</code>, ... described
+below.  
+<em>Accessing local variables declared in the method is not allowed</em>
+although declaring a new local variable in the block is allowed.
+However, <code>insertAt()</code> allows the statement and the block
+to access local variables
+if these variables are available at the specified line number
+and the target method was compiled with the -g option.
+
 
 <!--
 <p><center><table border=8 cellspacing=0 bordercolor="#cfcfcf">
@@ -166,8 +174,8 @@ below.  Declaring a local variable in the block is allowed.
 -->
 
 <p>The <code>String</code> object passed to the methods
-<code>insertBefore()</code>, <code>insertAfter()</code>, and
-<code>addCatch()</code> are compiled by
+<code>insertBefore()</code>, <code>insertAfter()</code>,
+<code>addCatch()</code>, and <code>insertAt()</code> are compiled by
 the compiler included in Javassist.
 Since the compiler supports language extensions,
 several identifiers starting with <code>$</code>
@@ -239,8 +247,7 @@ the class currently edited.</td>
 
 <h4>$0, $1, $2, ...</h4>
 
-<p>The parameters passed to the methods <code>insertBefore()</code>,
-<code>insertAfter()</code>, and <code>addCatch()</code>
+<p>The parameters passed to the target method
 are accessible with
 <code>$0</code>, <code>$1</code>, <code>$2</code>, ... instead of
 the original parameter names.
@@ -685,6 +692,12 @@ object creation, or others.  The second statement could be:
 
 <p>if the expression is write access.
 
+<p>Local variables available in the target expression is
+also available in the source text passed to <code>replace()</code>
+if the method searched by <code>instrument()</code> was compiled
+with the -g option (the class file includes a local variable
+attribute).
+
 <h4>javassist.expr.MethodCall</h4>
 
 <p>A <code>MethodCall</code> object represents a method call.
@@ -1318,6 +1331,6 @@ write:
 
 <hr>
 Java(TM) is a trademark of Sun Microsystems, Inc.<br>
-Copyright (C) 2000-2003 by Shigeru Chiba, All rights reserved.
+Copyright (C) 2000-2004 by Shigeru Chiba, All rights reserved.
 </body>
 </html>