实现ClassVisitor接口

package com.uwo.resources.asm.test;import org.objectweb.asm.*;/** * Created by yanhao on 2017/5/15. */public class UwoClassVisitor implements ClassVisitor{    public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {        System.out.println("visit");    }    public void visitOuterClass(String owner, String name, String desc) {        System.out.println("visitOuterClass");    }    public void visitInnerClass(String name, String outerName, String innerName, int access) {        System.out.println("visitInnerClass");    }    public void visitAttribute(Attribute attr) {        System.out.println("visitAttribute");    }    public void visitSource(String source, String debug) {        System.out.println("visitSource");    }    public AnnotationVisitor visitAnnotation(String desc, boolean visible) {        System.out.println("Annotation===========start==========");        System.out.println("Annotation desc = " + desc);        System.out.println("Annotation visible = " + visible);        System.out.println("Annotation===========end==========");        return null;    }    public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {        System.out.println("Field===========start==========");        System.out.println("Field access = " + access);        System.out.println("Field name = " + name);        System.out.println("Field desc = " + desc);        System.out.println("Field signature = " + signature);        System.out.println("Field value = " + value);        System.out.println("Field===========end==========");        return null;    }    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {        System.out.println("Method===========start==========");        System.out.println("Method access = " + access);        System.out.println("Method name = " + name);        System.out.println("Method desc = " + desc);        System.out.println("Method signature = " + signature);        System.out.println("Method exceptions = " + exceptions);        System.out.println("Method===========end==========");        return null;    }    public void visitEnd() {        System.out.println("visitEnd");    }}

执行代码

try {    ClassReader cr = new ClassReader(Uwo.class.getName());    cr.accept(new UwoClassVisitor(), 0);} catch (IOException e) {    e.printStackTrace();}

执行结果

visitvisitSourceField===========start==========Field access = 4Field name = nameField desc = Ljava/lang/String;Field signature = nullField value = nullField===========end==========Field===========start==========Field access = 4Field name = sexField desc = Ljava/lang/Integer;Field signature = nullField value = nullField===========end==========Method===========start==========Method access = 1Method name = 
    
     Method desc = (Ljava/lang/String;)VMethod signature = nullMethod exceptions = nullMethod===========end==========Method===========start==========Method access = 1Method name = helloMethod desc = (Ljava/lang/String;)Ljava/lang/String;Method signature = nullMethod exceptions = nullMethod===========end==========Method===========start==========Method access = 1Method name = runMethod desc = ()VMethod signature = nullMethod exceptions = nullMethod===========end==========visitEnd