com.blade.kit.AsmKit Maven / Gradle / Ivy
/**
* Copyright (c) 2016, biezhi 王爵 ([email protected])
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.blade.kit;
import lombok.experimental.UtilityClass;
import org.objectweb.asm.*;
import java.io.IOException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* ASM Tools
*
* @author biezhi
* @since 1.6.6
*/
@UtilityClass
public class AsmKit {
/**
* Cached method names
*/
private static final Map METHOD_NAMES_POOL = new ConcurrentHashMap<>(64);
/**
* Compare whether the parameter type is consistent
*
* @param types the type of the asm({@link Type})
* @param classes java type({@link Class})
* @return return param type equals
*/
private static boolean sameType(Type[] types, Class[] classes) {
if (types.length != classes.length) return false;
for (int i = 0; i < types.length; i++) {
if (!Type.getType(classes[i]).equals(types[i])) return false;
}
return true;
}
/**
* get method param names
*
* @param m method
* @return return method param names
*/
public static String[] getMethodParamNames(final Method m) {
if (METHOD_NAMES_POOL.containsKey(m)) return METHOD_NAMES_POOL.get(m);
final String[] paramNames = new String[m.getParameterTypes().length];
final String n = m.getDeclaringClass().getName();
ClassReader cr;
try {
cr = new ClassReader(n);
} catch (IOException e) {
return null;
}
cr.accept(new ClassVisitor(Opcodes.ASM5) {
@Override
public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) {
final Type[] args = Type.getArgumentTypes(desc);
// The method name is the same and the number of parameters is the same
if (!name.equals(m.getName()) || !sameType(args, m.getParameterTypes())) {
return super.visitMethod(access, name, desc, signature, exceptions);
}
MethodVisitor v = super.visitMethod(access, name, desc, signature, exceptions);
return new MethodVisitor(Opcodes.ASM5, v) {
@Override
public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
int i = index - 1;
// if it is a static method, the first is the parameter
// if it's not a static method, the first one is "this" and then the parameter of the method
if (Modifier.isStatic(m.getModifiers())) {
i = index;
}
if (i >= 0 && i < paramNames.length) {
paramNames[i] = name;
}
super.visitLocalVariable(name, desc, signature, start, end, index);
}
};
}
}, 0);
METHOD_NAMES_POOL.put(m, paramNames);
return paramNames;
}
}