package com.coshaho.learn.javassist;

import java.io.File;

import java.io.FileOutputStream;

import javassist.ClassPool;

import javassist.CtClass;

import javassist.CtMethod;

import javassist.Modifier;

import javassist.bytecode.AnnotationsAttribute;

import javassist.bytecode.ClassFile;

import javassist.bytecode.ConstPool;

import javassist.bytecode.ParameterAnnotationsAttribute;

import javassist.bytecode.annotation.Annotation;

import javassist.bytecode.annotation.StringMemberValue;

public class DynamicWebserviceGenerator

{

	public Class<?> createDynamicClazz() throws Exception

	{

		ClassPool pool = ClassPool.getDefault();

		// 创建类

		CtClass cc = pool.makeClass("com.coshaho.learn.DynamicHelloWorld");

		// 创建方法

	    CtClass ccStringType = pool.get("java.lang.String");

		// 参数：  1：返回类型  2：方法名称  3：传入参数类型  4：所属类CtClass

		CtMethod ctMethod=new CtMethod(ccStringType,"sayHello",new CtClass[]{ccStringType},cc);

		ctMethod.setModifiers(Modifier.PUBLIC);

		StringBuffer body=new StringBuffer();

		body.append("{");

		body.append("\n    System.out.println($1);");

		body.append("\n    return \"Hello, \" + $1;");

		body.append("\n}");

		ctMethod.setBody(body.toString());

		cc.addMethod(ctMethod);  

		ClassFile ccFile = cc.getClassFile();

		ConstPool constPool = ccFile.getConstPool();

		// 添加类注解

		AnnotationsAttribute bodyAttr = new AnnotationsAttribute(constPool, AnnotationsAttribute.visibleTag);

		Annotation bodyAnnot = new Annotation("javax.jws.WebService", constPool);

		bodyAnnot.addMemberValue("name", new StringMemberValue("HelloWoldService", constPool));

		bodyAttr.addAnnotation(bodyAnnot);

		ccFile.addAttribute(bodyAttr);

		// 添加方法注解

		AnnotationsAttribute methodAttr = new AnnotationsAttribute(constPool, AnnotationsAttribute.visibleTag);

		Annotation methodAnnot = new Annotation("javax.jws.WebMethod", constPool);

		methodAnnot.addMemberValue("operationName", new StringMemberValue("sayHelloWorld", constPool));

		methodAttr.addAnnotation(methodAnnot);

		Annotation resultAnnot = new Annotation("javax.jws.WebResult", constPool);

		resultAnnot.addMemberValue("name", new StringMemberValue("result", constPool));

		methodAttr.addAnnotation(resultAnnot);

		ctMethod.getMethodInfo().addAttribute(methodAttr);

		// 添加参数注解

		ParameterAnnotationsAttribute parameterAtrribute = new ParameterAnnotationsAttribute(

				constPool, ParameterAnnotationsAttribute.visibleTag);

	    Annotation paramAnnot = new Annotation("javax.jws.WebParam", constPool);

	    paramAnnot.addMemberValue("name", new StringMemberValue("name",constPool));

	    Annotation[][] paramArrays = new Annotation[1][1];

	    paramArrays[0][0] = paramAnnot;

	    parameterAtrribute.setAnnotations(paramArrays);

	    ctMethod.getMethodInfo().addAttribute(parameterAtrribute);

		//把生成的class文件写入文件

		byte[] byteArr = cc.toBytecode();

		FileOutputStream fos = new FileOutputStream(new File("D://DynamicHelloWorld.class"));

		fos.write(byteArr);

		fos.close();

		return cc.toClass();

	}

}

package com.coshaho.learn.javassist;

import org.apache.cxf.endpoint.Server;

import org.apache.cxf.jaxws.JaxWsServerFactoryBean;

public class DynamicWebServiceServer

{

    public static void main(String[] args) throws Exception

    {

        DynamicWebserviceGenerator javassistLearn = new DynamicWebserviceGenerator();

        Class<?> webservice = javassistLearn.createDynamicClazz();

        JaxWsServerFactoryBean factoryBean = new JaxWsServerFactoryBean();

        // Web服务的地址

        factoryBean.setAddress("http://localhost:8081/dynamicHello");

        // Web服务对象调用接口

        factoryBean.setServiceClass(webservice);

        Server server = factoryBean.create();

        server.start();

    }

}