Hessian相关(转载)

Hessian is a simple binary protocol for connecting web services. The com.caucho.hessian.client and com.caucho.hessian.server packages do not require any other Resin classes, so can be used in smaller clients, like applets.

利用Hessian 实现webService的发布是一种很简单的方式，下面写个简单的例子。

1. 编写要发布的服务接口

package com.lht;

public interface ISomeService {
public String hello();
public int add(int a,int b);
}

package com.lht;

public interface ISomeService {
public String hello();
public int add(int a,int b);
}

2. 编写实现类

package com.lht;

public class SomeServiceImpl implements ISomeService {

    public String hello() {
        // TODO Auto-generated method stub
        return "hello HessianDemo";
    }

    public int add(int a, int b) {
        // TODO Auto-generated method stub
        return a+b;
    }
}

package com.lht;

public class SomeServiceImpl implements ISomeService {

	public String hello() {
		// TODO Auto-generated method stub
		return "hello HessianDemo";
	}

	public int add(int a, int b) {
		// TODO Auto-generated method stub
		return a+b;
	}
}

3. 配置信息

<web-app>
<servlet>
   <servlet-name>hello</servlet-name>
   <servlet-class>com.caucho.hessian.server.HessianServlet</servlet-class>
    <init-param>
      <param-name>home-class</param-name>
      <param-value>example.BasicService</param-value>
    </init-param>
    <init-param>
      <param-name>home-api</param-name>
      <param-value>example.Basic</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <url-pattern>/hello</url-pattern>
    <servlet-name>hello</servlet-name>
  </servlet-mapping>

</web-app>

<web-app>
<servlet>
   <servlet-name>hello</servlet-name>
   <servlet-class>com.caucho.hessian.server.HessianServlet</servlet-class>
    <init-param>
      <param-name>home-class</param-name>
      <param-value>example.BasicService</param-value>
    </init-param>
    <init-param>
      <param-name>home-api</param-name>
      <param-value>example.Basic</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <url-pattern>/hello</url-pattern>
    <servlet-name>hello</servlet-name>
  </servlet-mapping>
  
</web-app>

总结：
利用Hessian  实现分布式，变的相当的简单，就和开发简单的servlet一般。

Hessian的这个远程过程调用，完全使用动态代理来实现的，其实从客户端代码不难看出，HessianProxyFactory的create方法就是创建接口Basic的代理类，该类实现了Basic接口，JDK的proxy类会自动用 InvocationHandler 的实现类（该类在Hessian中表现为HessianProxy）的invoke方法体 来填充所生成代理类的方法体，从而实现远程调用，传输过程使用的是基于Http的二进制字节流。

RMI与Hessian的调用过程比较：
Hessian：客户端（basic.hello()）——>序列化写到输出流——>远程方法（服务器端）——>序列化写到输出流 ——>客户端读取输入流——>输出结果
RMI：客户端——>stub——>序列化——>skeleton——>远程方法——>序列化——>stub—— >输出结果

参考信息
1.http://hessian.caucho.com/
2.http://eis.blogdriver.com/eis/331413.html

 

 

几种基于HTTP协议的RPC性能比较

关键字: burlap hessian

有了整体的了解后，可以发现Hessian的这个远程过程调用，完全使用动态代理来实现的，其实从客户端代码不难看出，HessianProxyFactory的create方法就是创建接口Basic的代理类，该类实现了Basic接口，JDK的proxy类会自动用 InvocationHandler 的实现类（该类在Hessian中表现为HessianProxy）的invoke方法体 来填充所生成代理类的方法体，从而实现远程调用，传输过程使用的是基于Http的二进制字节流。

RMI与Hessian的调用过程比较：

Hessian：客户端（basic.hello()）——>序列化写到输出流——>远程方法（服务器端）——>序列化写到输出流 ——>客户端读取输入流——>输出结果
RMI：客户端——>stub——>序列化——>skeleton——>远程方法——>序列化——>stub—— >输出结果

Hessian：客户端（basic.hello()）——>序列化写到输出流——>远程方法（服务器端）——>序列化写到输出流 ——>客户端读取输入流——>输出结果
RMI：客户端——>stub——>序列化——>skeleton——>远程方法——>序列化——>stub—— >输出结果

服务端的是一个简单的加密、解密方法，各种协议使用同一个实现的代码。
客户端是独立的java程序，分别用各种协议对服务端的方法进行调用。每一种协议循环调用n次，然后取平均值。

循环1,000次的测试
第一次

Axis --------------->> Total time: 11123 ms, Avg time: 11.123 ms
Burlap ------------->> Total time:   866 ms, Avg time:  0.866 ms
Hessian ------------>> Total time:   581 ms, Avg time:  0.581 ms
REST --------------->> Total time:   929 ms, Avg time:  0.929 ms
AxisUsingWSDL2Java ->> Total time: 11998 ms, Avg time: 11.998 ms

Axis --------------->> Total time: 11123 ms, Avg time: 11.123 ms
Burlap ------------->> Total time:   866 ms, Avg time:  0.866 ms
Hessian ------------>> Total time:   581 ms, Avg time:  0.581 ms
REST --------------->> Total time:   929 ms, Avg time:  0.929 ms
AxisUsingWSDL2Java ->> Total time: 11998 ms, Avg time: 11.998 ms

第二次

Axis --------------->> Total time: 11256 ms, Avg time: 11.256 ms
Burlap ------------->> Total time:   816 ms, Avg time:  0.816 ms
Hessian ------------>> Total time:   582 ms, Avg time:  0.582 ms
REST --------------->> Total time:   919 ms, Avg time:  0.919 ms
AxisUsingWSDL2Java ->> Total time: 11908 ms, Avg time: 11.908 ms

Axis --------------->> Total time: 11256 ms, Avg time: 11.256 ms
Burlap ------------->> Total time:   816 ms, Avg time:  0.816 ms
Hessian ------------>> Total time:   582 ms, Avg time:  0.582 ms
REST --------------->> Total time:   919 ms, Avg time:  0.919 ms
AxisUsingWSDL2Java ->> Total time: 11908 ms, Avg time: 11.908 ms

循环10,000次的测试
第一次

Axis --------------->> Total time:  88013 ms, Avg time:  8.8013 ms
Burlap ------------->> Total time:   5789 ms, Avg time:  0.5789 ms
Hessian ------------>> Total time:   5162 ms, Avg time:  0.5162 ms
REST --------------->> Total time:   8316 ms, Avg time:  0.8316 ms
AxisUsingWSDL2Java ->> Total time: 112801 ms, Avg time: 11.2801 ms

Axis --------------->> Total time:  88013 ms, Avg time:  8.8013 ms
Burlap ------------->> Total time:   5789 ms, Avg time:  0.5789 ms
Hessian ------------>> Total time:   5162 ms, Avg time:  0.5162 ms
REST --------------->> Total time:   8316 ms, Avg time:  0.8316 ms
AxisUsingWSDL2Java ->> Total time: 112801 ms, Avg time: 11.2801 ms

第二次

Axis --------------->> Total time:  87359 ms, Avg time:  8.7359 ms
Burlap ------------->> Total time:   5784 ms, Avg time:  0.5784 ms
Hessian ------------>> Total time:   5084 ms, Avg time:  0.5084 ms
REST --------------->> Total time:   7983 ms, Avg time:  0.7983 ms
AxisUsingWSDL2Java ->> Total time: 113234 ms, Avg time: 11.3234 ms

Axis --------------->> Total time:  87359 ms, Avg time:  8.7359 ms
Burlap ------------->> Total time:   5784 ms, Avg time:  0.5784 ms
Hessian ------------>> Total time:   5084 ms, Avg time:  0.5084 ms
REST --------------->> Total time:   7983 ms, Avg time:  0.7983 ms
AxisUsingWSDL2Java ->> Total time: 113234 ms, Avg time: 11.3234 ms

测试结果
Hessian最快，Burlap第二，REST第三，Axis最慢。前3种要比Axis快了10倍或者更多。

上面的测试，服务端用的是Resin-3.0.13，出于好奇，我又用Tomcat-5.5.9测试了一把，结果是Resin确实比Tomcat快些。Tomcat-5.5.9 循环10,000次的测试