Java tutorial
/** * Copyright (c) Lambda Innovation, 2013-2015 * ??Lambda Innovation * http://www.li-dev.cn/ * * This project is open-source, and it is distributed under * the terms of GNU General Public License. You can modify * and distribute freely as long as you follow the license. * ??GNU??? * ???? * http://www.gnu.org/licenses/gpl.html */ package cn.annoreg.asm; import net.minecraft.entity.player.EntityPlayer; import org.objectweb.asm.AnnotationVisitor; import org.objectweb.asm.ClassVisitor; import org.objectweb.asm.ClassWriter; import org.objectweb.asm.Label; import org.objectweb.asm.MethodVisitor; import org.objectweb.asm.Opcodes; import org.objectweb.asm.Type; import cn.annoreg.mc.network.NetworkCallDelegate; import cn.annoreg.mc.network.NetworkCallManager; import cn.annoreg.mc.s11n.StorageOption; import cpw.mods.fml.relauncher.Side; public class DelegateGenerator { /** * Class loader used to generate delegate class. * */ private static class DelegateClassLoader extends ClassLoader { public DelegateClassLoader() { super(NetworkCallDelegate.class.getClassLoader()); } public Class<?> defineClass(String name, byte[] b) { return defineClass(name, b, 0, b.length); } } private static void pushIntegerConst(MethodVisitor mv, int val) { mv.visitLdcInsn(val); //mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, Type.getInternalName(Integer.class), // "intValue", Type.getMethodDescriptor(Type.INT_TYPE)); } private static final DelegateClassLoader classLoader = new DelegateClassLoader(); private static int delegateNextID = 0; public static MethodVisitor generateStaticMethod(ClassVisitor parentClass, MethodVisitor parent, String className, String methodName, String desc, final Side side) { //This method is a little bit complicated. //We need to generate a delegate class implementing NetworkCallDelegate and a redirect //the code that originally generated here in parent, into the delegate class, //by returning a MethodVisitor under the ClassVisitor of the delegate class. //Besides, we should generate a call to NetworkCallManager into parent. //Above is the original method. Now it has a little bit change. To allow private call in //here, we need to generate the delegate method in this class instead of in a delegate class. //We make the delegate method public so that the delegate class can call it. //delegateName is a string used by both sides to identify a network-call delegate. final String delegateName = className + ":" + methodName + ":" + desc; final Type[] args = Type.getArgumentTypes(desc); final Type ret = Type.getReturnType(desc); //Check types for (Type t : args) { //TODO support these types if (!t.getDescriptor().startsWith("L") && !t.getDescriptor().startsWith("[")) { throw new RuntimeException("Unsupported argument type in network call. in method " + methodName + ", " + t.getDescriptor()); } } if (!ret.equals(Type.VOID_TYPE)) { throw new RuntimeException( "Unsupported return value type in network call. " + "Only void is supported."); } //Generate call to NetworkCallManager in parent. parent.visitCode(); //First parameter parent.visitLdcInsn(delegateName); //Second parameter: object array pushIntegerConst(parent, args.length); //array size parent.visitTypeInsn(Opcodes.ANEWARRAY, Type.getInternalName(Object.class)); for (int i = 0; i < args.length; ++i) { parent.visitInsn(Opcodes.DUP); pushIntegerConst(parent, i); parent.visitVarInsn(Opcodes.ALOAD, i); parent.visitInsn(Opcodes.AASTORE); } //Call cn.annoreg.mc.network.NetworkCallManager.onNetworkCall parent.visitMethodInsn(Opcodes.INVOKESTATIC, Type.getInternalName(NetworkCallManager.class), "onNetworkCall", Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(String.class), Type.getType(Object[].class))); parent.visitInsn(Opcodes.RETURN); parent.visitMaxs(5, args.length); parent.visitEnd(); //Create delegate object. final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS); final String delegateId = Integer.toString(delegateNextID++); final Type delegateClassType = Type.getType("cn/annoreg/asm/NetworkCallDelegate_" + delegateId); cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, delegateClassType.getInternalName(), null, Type.getInternalName(Object.class), new String[] { Type.getInternalName(NetworkCallDelegate.class) }); //package cn.annoreg.asm; //class NetworkCallDelegate_? implements NetworkCallDelegate { { MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null); mv.visitCode(); mv.visitVarInsn(Opcodes.ALOAD, 0); mv.visitMethodInsn(Opcodes.INVOKESPECIAL, Type.getInternalName(Object.class), "<init>", "()V"); mv.visitInsn(Opcodes.RETURN); mv.visitMaxs(1, 1); mv.visitEnd(); } //public NetworkCallDelegate_?() {} final String delegateFunctionName = methodName + "_delegate_" + delegateId; { MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "invoke", Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(Object[].class)), null, null); mv.visitCode(); for (int i = 0; i < args.length; ++i) { mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this pushIntegerConst(mv, i); mv.visitInsn(Opcodes.AALOAD); mv.visitTypeInsn(Opcodes.CHECKCAST, args[i].getInternalName()); } mv.visitMethodInsn(Opcodes.INVOKESTATIC, //delegateClassType.getInternalName(), //changed to original class className.replace('.', '/'), delegateFunctionName, desc); mv.visitInsn(Opcodes.RETURN); mv.visitMaxs(args.length + 2, 2); mv.visitEnd(); } //@Override public void invoke(Object[] args) { // xxxx.xxxx_delegated_xxx((Type0) args[0], (Type1) args[1], ...); //} //The returned MethodVisitor will visit the original version of the method, //including its annotation, where we can get StorageOptions. return new MethodVisitor(Opcodes.ASM4, parentClass.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, delegateFunctionName, desc, null, null)) { //Remember storage options for each argument StorageOption.Option[] options = new StorageOption.Option[args.length]; int targetIndex = -1; StorageOption.Target.RangeOption range = StorageOption.Target.RangeOption.SINGLE; double sendRange = -1; { for (int i = 0; i < options.length; ++i) { options[i] = StorageOption.Option.NULL; //set default value } } @Override public AnnotationVisitor visitParameterAnnotation(final int parameter, String desc, boolean visible) { Type type = Type.getType(desc); if (type.equals(Type.getType(StorageOption.Data.class))) { options[parameter] = StorageOption.Option.DATA; } else if (type.equals(Type.getType(StorageOption.Instance.class))) { //INSTANCE as defualt options[parameter] = StorageOption.Option.INSTANCE; //Change to NULLABLE_INSTANCE if nullable set to true return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visit(String name, Object value) { if (name.equals("nullable")) { if ((Boolean) value == true) { options[parameter] = StorageOption.Option.NULLABLE_INSTANCE; } } super.visit(name, value); } }; } else if (type.equals(Type.getType(StorageOption.Update.class))) { options[parameter] = StorageOption.Option.UPDATE; } else if (type.equals(Type.getType(StorageOption.Null.class))) { options[parameter] = StorageOption.Option.NULL; } else if (type.equals(Type.getType(StorageOption.Target.class))) { if (!args[parameter].equals(Type.getType(EntityPlayer.class))) { throw new RuntimeException("Target annotation can only be used on EntityPlayer."); } if (targetIndex != -1) { throw new RuntimeException("You can not specify multiple targets."); } options[parameter] = StorageOption.Option.INSTANCE; targetIndex = parameter; return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visitEnum(String name, String desc, String value) { super.visitEnum(name, desc, value); range = StorageOption.Target.RangeOption.valueOf(value); } }; } else if (type.equals(Type.getType(StorageOption.RangedTarget.class))) { if (targetIndex != -1) { throw new RuntimeException("You can not specify multiple targets."); } range = null; targetIndex = parameter; return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visit(String name, Object value) { super.visit(name, value); sendRange = (double) value; } }; } return super.visitParameterAnnotation(parameter, desc, visible); } @Override public void visitEnd() { super.visitEnd(); //This is the last method in the delegate class. //Finish the class and do the registration. cw.visitEnd(); try { Class<?> clazz = classLoader.defineClass(delegateClassType.getClassName(), cw.toByteArray()); NetworkCallDelegate delegateObj = (NetworkCallDelegate) clazz.newInstance(); if (side == Side.CLIENT) { NetworkCallManager.registerClientDelegateClass(delegateName, delegateObj, options, targetIndex, range, sendRange); } else { NetworkCallManager.registerServerDelegateClass(delegateName, delegateObj, options); } } catch (Throwable e) { throw new RuntimeException("Can not create delegate for network call.", e); } } }; //public static void delegated(Type0 arg0, Type1, arg1, ...) { // //Code generated by caller. //} //} } public static MethodVisitor generateNonStaticMethod(ClassVisitor parentClass, MethodVisitor parent, String className, String methodName, String desc, final Side side) { //convert desc to a non-static method form String nonstaticDesc; { Type staticType = Type.getMethodType(desc); Type retType = staticType.getReturnType(); Type[] argsType = staticType.getArgumentTypes(); Type[] argsTypeWithThis = new Type[argsType.length + 1]; argsTypeWithThis[0] = Type.getType('L' + className.replace('.', '/') + ';'); System.arraycopy(argsType, 0, argsTypeWithThis, 1, argsType.length); nonstaticDesc = Type.getMethodDescriptor(retType, argsTypeWithThis); } //delegateName is a string used by both sides to identify a network-call delegate. final String delegateName = className + ":" + methodName + ":" + desc; final Type[] args = Type.getArgumentTypes(nonstaticDesc); final Type ret = Type.getReturnType(nonstaticDesc); //Check types for (Type t : args) { //TODO support these types if (!t.getDescriptor().startsWith("L") && !t.getDescriptor().startsWith("[")) { throw new RuntimeException("Unsupported argument type in network call. "); } } if (!ret.equals(Type.VOID_TYPE)) { throw new RuntimeException( "Unsupported return value type in network call. " + "Only void is supported."); } //Generate call to NetworkCallManager in parent. parent.visitCode(); //First parameter parent.visitLdcInsn(delegateName); //Second parameter: object array pushIntegerConst(parent, args.length); //this (0) has been included parent.visitTypeInsn(Opcodes.ANEWARRAY, "java/lang/Object"); for (int i = 0; i < args.length; ++i) { parent.visitInsn(Opcodes.DUP); pushIntegerConst(parent, i); parent.visitVarInsn(Opcodes.ALOAD, i); parent.visitInsn(Opcodes.AASTORE); } //Call cn.annoreg.mc.network.NetworkCallManager.onNetworkCall parent.visitMethodInsn(Opcodes.INVOKESTATIC, Type.getInternalName(NetworkCallManager.class), "onNetworkCall", "(Ljava/lang/String;[Ljava/lang/Object;)V"); parent.visitInsn(Opcodes.RETURN); parent.visitMaxs(5, args.length); parent.visitEnd(); //Create delegate object. final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS); final String delegateId = Integer.toString(delegateNextID++); final Type delegateClassType = Type.getType("cn/annoreg/asm/NetworkCallDelegate_" + delegateId); cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, delegateClassType.getInternalName(), null, Type.getInternalName(Object.class), new String[] { Type.getInternalName(NetworkCallDelegate.class) }); //package cn.annoreg.asm; //class NetworkCallDelegate_? implements NetworkCallDelegate { { MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null); mv.visitCode(); mv.visitVarInsn(Opcodes.ALOAD, 0); mv.visitMethodInsn(Opcodes.INVOKESPECIAL, Type.getInternalName(Object.class), "<init>", "()V"); mv.visitInsn(Opcodes.RETURN); mv.visitMaxs(1, 1); mv.visitEnd(); } //public NetworkCallDelegate_?() {} final String delegateMethodName = methodName + "_delegate_" + delegateId; { MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "invoke", Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(Object[].class)), null, null); mv.visitCode(); //check if this is null mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this pushIntegerConst(mv, 0); mv.visitInsn(Opcodes.AALOAD); Label lblEnd = new Label(); mv.visitJumpInsn(Opcodes.IFNULL, lblEnd); for (int i = 0; i < args.length; ++i) { mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this pushIntegerConst(mv, i); mv.visitInsn(Opcodes.AALOAD); mv.visitTypeInsn(Opcodes.CHECKCAST, args[i].getInternalName()); } mv.visitMethodInsn(Opcodes.INVOKESTATIC, //delegateClassType.getInternalName(), className.replace('.', '/'), delegateMethodName, nonstaticDesc); mv.visitLabel(lblEnd); mv.visitInsn(Opcodes.RETURN); mv.visitMaxs(args.length + 2, 2); mv.visitEnd(); } //@Override public void invoke(Object[] args) { // delegated((Type0) args[0], (Type1) args[1], ...); //} //The returned MethodVisitor will visit the original version of the method, //including its annotation, where we can get StorageOptions. return new MethodVisitor(Opcodes.ASM4, parentClass.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, delegateMethodName, nonstaticDesc, null, null)) { //Remember storage options for each argument StorageOption.Option[] options = new StorageOption.Option[args.length]; int targetIndex = -1; double sendRange = -1; StorageOption.Target.RangeOption range = StorageOption.Target.RangeOption.SINGLE; { for (int i = 0; i < options.length; ++i) { options[i] = StorageOption.Option.NULL; //set default value } options[0] = StorageOption.Option.INSTANCE; } @Override public AnnotationVisitor visitParameterAnnotation(int parameter_in_func, String desc, boolean visible) { final int parameter = parameter_in_func + 1; //skip this Type type = Type.getType(desc); if (type.equals(Type.getType(StorageOption.Data.class))) { options[parameter] = StorageOption.Option.DATA; } else if (type.equals(Type.getType(StorageOption.Instance.class))) { //INSTANCE as defualt options[parameter] = StorageOption.Option.INSTANCE; //Change to NULLABLE_INSTANCE if nullable set to true return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visit(String name, Object value) { if (name.equals("nullable")) { if ((Boolean) value == true) { options[parameter] = StorageOption.Option.NULLABLE_INSTANCE; } } super.visit(name, value); } }; } else if (type.equals(Type.getType(StorageOption.Update.class))) { options[parameter] = StorageOption.Option.UPDATE; } else if (type.equals(Type.getType(StorageOption.Null.class))) { options[parameter] = StorageOption.Option.NULL; } else if (type.equals(Type.getType(StorageOption.Target.class))) { if (!args[parameter].equals(Type.getType(EntityPlayer.class))) { throw new RuntimeException("Target annotation can only be used on EntityPlayer."); } if (targetIndex != -1) { throw new RuntimeException("You can not specify multiple targets."); } options[parameter] = StorageOption.Option.INSTANCE; targetIndex = parameter; return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visitEnum(String name, String desc, String value) { super.visitEnum(name, desc, value); range = StorageOption.Target.RangeOption.valueOf(value); } }; } else if (type.equals(Type.getType(StorageOption.RangedTarget.class))) { if (targetIndex != -1) { throw new RuntimeException("You can not specify multiple targets."); } targetIndex = parameter; range = null; return new AnnotationVisitor(this.api, super.visitParameterAnnotation(parameter, desc, visible)) { @Override public void visit(String name, Object value) { super.visit(name, value); sendRange = (double) value; } }; } return super.visitParameterAnnotation(parameter, desc, visible); } //TODO this option (from annotation) @Override public void visitEnd() { super.visitEnd(); //This is the last method in the delegate class. //Finish the class and do the registration. cw.visitEnd(); try { Class<?> clazz = classLoader.defineClass(delegateClassType.getClassName(), cw.toByteArray()); NetworkCallDelegate delegateObj = (NetworkCallDelegate) clazz.newInstance(); if (side == Side.CLIENT) { NetworkCallManager.registerClientDelegateClass(delegateName, delegateObj, options, targetIndex, range, sendRange); } else { NetworkCallManager.registerServerDelegateClass(delegateName, delegateObj, options); } } catch (Throwable e) { throw new RuntimeException("Can not create delegate for network call.", e); } } }; //public static void delegated(Type0 arg0, Type1, arg1, ...) { // //Code generated by caller. //} //} } }