diff options
| -rw-r--r-- | src/main/javassist/CodeConverter.java | 30 | ||||
| -rw-r--r-- | src/main/javassist/convert/TransformNewClass.java | 82 |
2 files changed, 110 insertions, 2 deletions
diff --git a/src/main/javassist/CodeConverter.java b/src/main/javassist/CodeConverter.java index 4ffe1eeb..91f5657a 100644 --- a/src/main/javassist/CodeConverter.java +++ b/src/main/javassist/CodeConverter.java @@ -98,6 +98,32 @@ public class CodeConverter { } /** + * Modify a method body so that instantiation of the class + * specified by <code>oldClass</code> + * is replaced with instantiation of another class <code>newClass</code>. + * For example, + * <code>replaceNew(ctPoint, ctPoint2)</code> + * (where <code>ctPoint</code> and <code>ctPoint2</code> are + * compile-time classes for class <code>Point</code> and class + * <code>Point2</code>, respectively) + * replaces all occurrences of: + * + * <ul><code>new Point(x, y)</code></ul> + * + * in the method body with: + * + * <ul><code>new Point2(x, y)</code></ul> + * + * <p>Note that <code>Point2</code> must be type-compatible with <code>Point</code>. + * It must have the same set of methods, fields, and constructors as the + * replaced class. + */ + public void replaceNew(CtClass oldClass, CtClass newClass) { + transformers = new TransformNewClass(transformers, oldClass.getName(), + newClass.getName()); + } + + /** * Modify a method body so that field read/write expressions access * a different field from the original one. * @@ -503,7 +529,7 @@ public class CodeConverter { * as array access replacements. * * @author <a href="kabir.khan@jboss.com">Kabir Khan</a> - * @version $Revision: 1.14 $ + * @version $Revision: 1.15 $ */ public interface ArrayAccessReplacementMethodNames { @@ -612,7 +638,7 @@ public class CodeConverter { * accesses to array elements. * * @author <a href="kabir.khan@jboss.com">Kabir Khan</a> - * @version $Revision: 1.14 $ + * @version $Revision: 1.15 $ */ public static class DefaultArrayAccessReplacementMethodNames implements ArrayAccessReplacementMethodNames diff --git a/src/main/javassist/convert/TransformNewClass.java b/src/main/javassist/convert/TransformNewClass.java new file mode 100644 index 00000000..f34ef83b --- /dev/null +++ b/src/main/javassist/convert/TransformNewClass.java @@ -0,0 +1,82 @@ +/* + * Javassist, a Java-bytecode translator toolkit. + * Copyright (C) 1999-2007 Shigeru Chiba. All Rights Reserved. + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. Alternatively, the contents of this file may be used under + * the terms of the GNU Lesser General Public License Version 2.1 or later. + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + */ + +package javassist.convert; + +import javassist.bytecode.*; +import javassist.CtClass; +import javassist.CannotCompileException; + +final public class TransformNewClass extends Transformer { + private int nested; + private String classname, newClassName; + private int newClassIndex, newMethodNTIndex, newMethodIndex; + + public TransformNewClass(Transformer next, + String classname, String newClassName) { + super(next); + this.classname = classname; + this.newClassName = newClassName; + } + + public void initialize(ConstPool cp, CodeAttribute attr) { + nested = 0; + newClassIndex = newMethodNTIndex = newMethodIndex = 0; + } + + /** + * Modifies a sequence of + * NEW classname + * DUP + * ... + * INVOKESPECIAL classname:method + */ + public int transform(CtClass clazz, int pos, CodeIterator iterator, + ConstPool cp) throws CannotCompileException + { + int index; + int c = iterator.byteAt(pos); + if (c == NEW) { + index = iterator.u16bitAt(pos + 1); + if (cp.getClassInfo(index).equals(classname)) { + if (iterator.byteAt(pos + 3) != DUP) + throw new CannotCompileException( + "NEW followed by no DUP was found"); + + if (newClassIndex == 0) + newClassIndex = cp.addClassInfo(newClassName); + + iterator.write16bit(newClassIndex, pos + 1); + ++nested; + } + } + else if (c == INVOKESPECIAL) { + index = iterator.u16bitAt(pos + 1); + int typedesc = cp.isConstructor(classname, index); + if (typedesc != 0 && nested > 0) { + int nt = cp.getMethodrefNameAndType(index); + if (newMethodNTIndex != nt) { + newMethodNTIndex = nt; + newMethodIndex = cp.addMethodrefInfo(newClassIndex, nt); + } + + iterator.write16bit(newMethodIndex, pos + 1); + --nested; + } + } + + return pos; + } +} |