Jvm之用C#解析class文件

项目地址

GitHub - lxw112190/JavaClassReader: C# JavaClassReader

项目结构

一个简单的测试类

public class Test {    Integer code = 123;    String name = "lxw";    void method1() { System.out.println("我是method1");    }    public static void main(String[] args) { System.out.println("我是main");    }}

效果

ClassReader

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.IO;using JavaClassReader.basictype;using JavaClassReader.constantinfo;using JavaClassReader.basicinfo;using JavaClassReader.basicinfo.instruction;using JavaClassReader.basicinfo.attribute;namespace JavaClassReader{    public class ClassReader    { public static string read(String classPath) {     StringBuilder info = new StringBuilder();     FileStream file = new FileStream(classPath, FileMode.Open, FileAccess.Read);     try     {  ClassFile classFile = new ClassFile();  classFile.magic = U4.read(file);  classFile.minorVersion = U2.read(file);  classFile.majorVersion = U2.read(file);  //解析常量池  int constant_pool_count = U2.read(file);  ConstantPool constantPool = new ConstantPool(constant_pool_count);  constantPool.read(file);  //获取常量池信息  string cpInfo = constantPool.printConstanPoolInfo(constantPool);  info.Append(cpInfo);  //获取类信息  classFile.accessFlag = U2.read(file);  int classIndex = U2.read(file);  ConstantClass clazz = (ConstantClass)constantPool.cpInfo[classIndex];  //获取类名，并将其转化为ContantClass类  ConstantUtf8 className = (ConstantUtf8)constantPool.cpInfo[clazz.nameIndex];  classFile.className = className.value;  info.Append("classname:" + classFile.className + "\n");  //获取父类信息  int superIndex = U2.read(file);  ConstantClass superClazz = (ConstantClass)constantPool.cpInfo[superIndex];  ConstantUtf8 superclassName = (ConstantUtf8)constantPool.cpInfo[superClazz.nameIndex];  classFile.superClass = superclassName.value;  info.Append("superclass:" + classFile.superClass + "\n");  //获取接口信息  classFile.interfaceCount = U2.read(file);  classFile.interfaces = new String[classFile.interfaceCount];  for (int i = 0; i < classFile.interfaceCount; i++)  {      int interfaceIndex = U2.read(file);      ConstantClass interfaceClazz = (ConstantClass)constantPool.cpInfo[interfaceIndex];      ConstantUtf8 interfaceName = (ConstantUtf8)constantPool.cpInfo[interfaceClazz.nameIndex];      classFile.interfaces[i] = interfaceName.value;      info.Append("interface:" + interfaceName.value + "\n");  }  info.Append("\n");  //获取字段信息  classFile.fieldCount = U2.read(file);  classFile.fields = new MemberInfo[classFile.fieldCount];  for (int i = 0; i < classFile.fieldCount; i++)  {      MemberInfo fieldInfo = new MemberInfo(constantPool);      fieldInfo.read(file);      info.Append("field:" + ((ConstantUtf8)constantPool.cpInfo[fieldInfo.nameIndex]).value + ", ");      info.Append("desc:" + ((ConstantUtf8)constantPool.cpInfo[fieldInfo.descriptorIndex]).value + "\n");  }  info.Append("\n");  //获取方法信息  classFile.methodCount = U2.read(file);  classFile.methods = new MemberInfo[classFile.methodCount];  for (int i = 0; i < classFile.methodCount; i++)  {      MemberInfo methodInfo = new MemberInfo(constantPool);      methodInfo.read(file);      info.Append("method:" + ((ConstantUtf8)constantPool.cpInfo[methodInfo.nameIndex]).value + "(), ");      info.Append("desc:" + ((ConstantUtf8)constantPool.cpInfo[methodInfo.descriptorIndex]).value + "\n");      for (int j = 0; j < methodInfo.attributesCount; j++)      {   if (methodInfo.attributes[j] is CodeAttribute)   {CodeAttribute codeAttribute = (CodeAttribute)methodInfo.attributes[j];for (int m = 0; m < codeAttribute.codeLength; m++){    short code = codeAttribute.code[m];    info.Append(InstructionTable.getInstruction(code) + "\n");}   }      }      info.Append("\n");  }     }     catch (FileNotFoundException e)     {  Console.Error.WriteLine(e);     }     return info.ToString(); }    }}