RPC(Remote Procedure Call) 在介绍分布是RPC前首先介绍一个下JAVA中简单的RPC实现
服务器端，通过SocketServer，持续接收客户端的请求，并将客户端的请求分发到指定的处理器出去处理。
阻塞通线模型，是server对每一个请求都开启一条线程去执行请求，此种方式的缺点是服务器端线程的数量和客户端并发访问请求树呈1:1的正比关系。
此处对此作出了一定优化，伪异步IO通信，将所有用户请求放到线程池中处理。
/**
*
* @author zhangwei_david
* @version $Id: ServiceServer.java, v 0.1 2015年8月8日 上午11:40:41 zhangwei_david Exp $
*/
public class ServiceServer implements InitializingBean, Lifecycle, ApplicationContextAware {
/**服务端口号**/
private int port = 12000;
private ServerSocket server;
//线程池
@Autowired
private Executor executorService;
public Map<String, Object> handlerMap = new ConcurrentHashMap<>();
private void publishedService() throws Exception {
server = new ServerSocket(port);
// 一直服务
for (;;) {
try {
// 获取socket
final Socket socket = server.accept();
executorService.execute(new Runnable() {
@Override
public void run() {
try {
// 获取input
ObjectInputStream input = new ObjectInputStream(socket.getInputStream());
ObjectOutputStream output = new ObjectOutputStream(socket
.getOutputStream());
try {
// 获取引用
String interfaceName = input.readUTF();
//获取 方法名
String methodName = input.readUTF();
//
Class<?>[] parameterTypes = (Class<?>[]) input.readObject();
Object[] arguments = (Object[]) input.readObject();
try {
Object service = handlerMap.get(interfaceName);
Method method = service.getClass().getMethod(methodName,
parameterTypes);
Object result = method.invoke(service, arguments);
output.writeObject(result);
} catch (Throwable t) {
output.writeObject(t);
} finally {
input.close();
}
} finally {
socket.close();
}
} catch (Exception e) {
}
}
});
} catch (Exception e) {
}
}
}
public void init() {
}
/**
* @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
*/
@Override
public void afterPropertiesSet() throws Exception {
//发布服务
publishedService();
}
/**
* @see org.springframework.context.Lifecycle#start()
*/
@Override
public void start() {
}
/**
* @see org.springframework.context.Lifecycle#stop()
*/
@Override
public void stop() {
if (server != null) {
try {
server.close();
} catch (IOException e) {
}
}
}
/**
* @see org.springframework.context.Lifecycle#isRunning()
*/
@Override
public boolean isRunning() {
return false;
}
/**
* @see org.springframework.context.ApplicationContextAware#setApplicationContext(org.springframework.context.ApplicationContext)
*/
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
Map<String, Object> serviceBeanMap = applicationContext.getBeansWithAnnotation(SRPC.class);
System.out.println(serviceBeanMap);
if (serviceBeanMap != null && !serviceBeanMap.isEmpty()) {
for (Object serviceBean : serviceBeanMap.values()) {
String interfaceName = serviceBean.getClass().getAnnotation(SRPC.class).interf()
.getName();
handlerMap.put(interfaceName, serviceBean);
}
}
}
/**
* Setter method for property <tt>executorService</tt>.
*
* @param executorService value to be assigned to property executorService
*/
public void setExecutorService(Executor executorService) {
this.executorService = executorService;
}
}
/**
*
* @author zhangwei_david
* @version $Id: SRPC.java, v 0.1 2015年8月8日 下午12:51:17 zhangwei_david Exp $
*/
@Documented
@Target({ ElementType.TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Component
public @interface SRPC {
public Class<?> interf();
}
至此就实现了服务的自动发现自动注册，当然这个仅针对单机环境下的自动注册。
/**
*
* @author zhangwei_david
* @version $Id: Client.java, v 0.1 2015年8月8日 下午12:28:44 zhangwei_david Exp $
*/
public class Client {
/**
* 引用服务
*
* @param <T> 接口泛型
* @param interfaceClass 接口类型
* @param host 服务器主机名
* @param port 服务器端口
* @return 远程服务
* @throws Exception
*/
@SuppressWarnings("unchecked")
public static <T> T refer(final Class<T> interfaceClass, final String host, final int port)
throws Exception {
if (interfaceClass == null || !interfaceClass.isInterface()) {
throw new IllegalArgumentException("必须指定服务接口");
}
if (host == null || host.length() == 0) {
throw new IllegalArgumentException("必须指定服务器的地址和端口号");
}
return (T) Proxy.newProxyInstance(interfaceClass.getClassLoader(),
new Class<?>[] { interfaceClass }, new InvocationHandler() {
@Override
public Object invoke(Object proxy, Method method, Object[] arguments)
throws Throwable {
Socket socket = new Socket(host, port);
try {
ObjectOutputStream output = new ObjectOutputStream(socket.getOutputStream());
try {
output.writeUTF(interfaceClass.getName());
output.writeUTF(method.getName());
output.writeObject(method.getParameterTypes());
output.writeObject(arguments);
ObjectInputStream input = new ObjectInputStream(socket.getInputStream());
try {
Object result = input.readObject();
if (result instanceof Throwable) {
throw (Throwable) result;
}
return result;
} finally {
input.close();
}
} finally {
output.close();
}
} finally {
socket.close();
}
}
});
}
}
上面在没有使用第三方依赖包实现了简单的RPC，优化增加 request和reponse,定义RPC协议。
/**
*
* @author zhangwei_david
* @version $Id: SrpcRequest.java, v 0.1 2015年8月8日 下午1:45:53 zhangwei_david Exp $
*/
public class SrpcRequest implements Serializable {
/** */
private static final long serialVersionUID = 6132853628325824727L;
// 请求Id
private String requestId;
// 远程调用接口名称
private String interfaceName;
//远程调用方法名称
private String methodName;
// 参数类型
private Class<?>[] parameterTypes;
// 参数值
private Object[] parameters;
/**
* Getter method for property <tt>requestId</tt>.
*
* @return property value of requestId
*/
public String getRequestId() {
return requestId;
}
/**
* Setter method for property <tt>requestId</tt>.
*
* @param requestId value to be assigned to property requestId
*/
public void setRequestId(String requestId) {
this.requestId = requestId;
}
/**
* Getter method for property <tt>interfaceName</tt>.
*
* @return property value of interfaceName
*/
public String getInterfaceName() {
return interfaceName;
}
/**
* Setter method for property <tt>interfaceName</tt>.
*
* @param interfaceName value to be assigned to property interfaceName
*/
public void setInterfaceName(String interfaceName) {
this.interfaceName = interfaceName;
}
/**
* Getter method for property <tt>methodName</tt>.
*
* @return property value of methodName
*/
public String getMethodName() {
return methodName;
}
/**
* Setter method for property <tt>methodName</tt>.
*
* @param methodName value to be assigned to property methodName
*/
public void setMethodName(String methodName) {
this.methodName = methodName;
}
/**
* Getter method for property <tt>parameterTypes</tt>.
*
* @return property value of parameterTypes
*/
public Class<?>[] getParameterTypes() {
return parameterTypes;
}
/**
* Setter method for property <tt>parameterTypes</tt>.
*
* @param parameterTypes value to be assigned to property parameterTypes
*/
public void setParameterTypes(Class<?>[] parameterTypes) {
this.parameterTypes = parameterTypes;
}
/**
* Getter method for property <tt>parameters</tt>.
*
* @return property value of parameters
*/
public Object[] getParameters() {
return parameters;
}
/**
* Setter method for property <tt>parameters</tt>.
*
* @param parameters value to be assigned to property parameters
*/
public void setParameters(Object[] parameters) {
this.parameters = parameters;
}
}
/**
*
* @author zhangwei_david
* @version $Id: SrpcResponse.java, v 0.1 2015年8月8日 下午1:47:46 zhangwei_david Exp $
*/
public class SrpcResponse implements Serializable {
/** */
private static final long serialVersionUID = -5934073769679010930L;
// 请求的Id
private String requestId;
// 异常
private Throwable error;
// 响应
private Object result;
/**
* Getter method for property <tt>requestId</tt>.
*
* @return property value of requestId
*/
public String getRequestId() {
return requestId;
}
/**
* Setter method for property <tt>requestId</tt>.
*
* @param requestId value to be assigned to property requestId
*/
public void setRequestId(String requestId) {
this.requestId = requestId;
}
/**
* Getter method for property <tt>error</tt>.
*
* @return property value of error
*/
public Throwable getError() {
return error;
}
/**
* Setter method for property <tt>error</tt>.
*
* @param error value to be assigned to property error
*/
public void setError(Throwable error) {
this.error = error;
}
/**
* Getter method for property <tt>result</tt>.
*
* @return property value of result
*/
public Object getResult() {
return result;
}
/**
* Setter method for property <tt>result</tt>.
*
* @param result value to be assigned to property result
*/
public void setResult(Object result) {
this.result = result;
}
}
/**
*
* @author zhangwei_david
* @version $Id: ServiceServer.java, v 0.1 2015年8月8日 上午11:40:41 zhangwei_david Exp $
*/
public class ServiceServer implements InitializingBean, Lifecycle, ApplicationContextAware {
/**服务端口号**/
private int port = 12000;
private ServerSocket server;
//线程池
@Autowired
private Executor executorService;
public Map<String, Object> handlerMap = new ConcurrentHashMap<>();
private void publishedService() throws Exception {
server = new ServerSocket(port);
// 一直服务
for (;;) {
try {
// 获取socket
final Socket socket = server.accept();
executorService.execute(new Runnable() {
@Override
public void run() {
try {
// 获取input
ObjectInputStream input = new ObjectInputStream(socket.getInputStream());
try {
// 获取RPC请求
SrpcRequest request = (SrpcRequest) input.readObject();
ObjectOutputStream output = new ObjectOutputStream(socket
.getOutputStream());
try {
SrpcResponse response = doHandle(request);
output.writeObject(response);
} finally {
input.close();
}
} finally {
socket.close();
}
} catch (Exception e) {
}
}
});
} catch (Exception e) {
}
}
}
private SrpcResponse doHandle(SrpcRequest request) {
SrpcResponse response = new SrpcResponse();
response.setRequestId(request.getRequestId());
try {
Object service = handlerMap.get(request.getInterfaceName());
Method method = service.getClass().getMethod(request.getMethodName(),
request.getParameterTypes());
response.setResult(method.invoke(service, request.getParameters()));
} catch (Exception e) {
response.setError(e);
}
return response;
}
public void init() {
}
/**
* @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
*/
@Override
public void afterPropertiesSet() throws Exception {
//发布
publishedService();
}
/**
* @see org.springframework.context.Lifecycle#start()
*/
@Override
public void start() {
}
/**
* @see org.springframework.context.Lifecycle#stop()
*/
@Override
public void stop() {
if (server != null) {
try {
server.close();
} catch (IOException e) {
}
}
}
/**
* @see org.springframework.context.Lifecycle#isRunning()
*/
@Override
public boolean isRunning() {
return false;
}
/**
* @see org.springframework.context.ApplicationContextAware#setApplicationContext(org.springframework.context.ApplicationContext)
*/
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
Map<String, Object> serviceBeanMap = applicationContext.getBeansWithAnnotation(SRPC.class);
System.out.println(serviceBeanMap);
if (serviceBeanMap != null && !serviceBeanMap.isEmpty()) {
for (Object serviceBean : serviceBeanMap.values()) {
String interfaceName = serviceBean.getClass().getAnnotation(SRPC.class).interf()
.getName();
handlerMap.put(interfaceName, serviceBean);
}
}
}
/**
* Setter method for property <tt>executorService</tt>.
*
* @param executorService value to be assigned to property executorService
*/
public void setExecutorService(Executor executorService) {
this.executorService = executorService;
}
}
/**
*
* @author zhangwei_david
* @version $Id: Client.java, v 0.1 2015年8月8日 下午12:28:44 zhangwei_david Exp $
*/
public class Client {
/**
* 引用服务
*
* @param <T> 接口泛型
* @param interfaceClass 接口类型
* @param host 服务器主机名
* @param port 服务器端口
* @return 远程服务
* @throws Exception
*/
@SuppressWarnings("unchecked")
public static <T> T refer(final Class<T> interfaceClass, final String host, final int port)
throws Exception {
if (interfaceClass == null || !interfaceClass.isInterface()) {
throw new IllegalArgumentException("必须指定服务接口");
}
if (host == null || host.length() == 0) {
throw new IllegalArgumentException("必须指定服务器的地址和端口号");
}
return (T) Proxy.newProxyInstance(interfaceClass.getClassLoader(),
new Class<?>[] { interfaceClass }, new InvocationHandler() {
@Override
public Object invoke(Object proxy, Method method, Object[] arguments)
throws Throwable {
Socket socket = new Socket(host, port);
try {
ObjectOutputStream output = new ObjectOutputStream(socket.getOutputStream());
try {
SrpcRequest request = new SrpcRequest();
request.setRequestId(UUID.randomUUID().toString());
request.setInterfaceName(interfaceClass.getName());
request.setMethodName(method.getName());
request.setParameterTypes(method.getParameterTypes());
request.setParameters(arguments);
output.writeObject(request);
ObjectInputStream input = new ObjectInputStream(socket.getInputStream());
try {
SrpcResponse response = (SrpcResponse) input.readObject();
if (response.getError() != null
&& response.getError() instanceof Throwable) {
throw response.getError();
}
return response.getResult();
} finally {
input.close();
}
} finally {
output.close();
}
} finally {
socket.close();
}
}
});
}
}