# 概述
通訊，源于網絡，網絡從下到上，分為7層：物理層、數據鏈路層、網絡層、傳輸層、會話層、表示層和應用層；通訊，基于協議，常用的協議有很多，比如網絡層協議IP、傳輸層協議TCP/UDP、應用層協議HTTP/SOAP/REST等。
我們還會經常聽到Socket，TCP/IP也要提供可供程序員做網絡開發所用的接口，這就是Socket編程接口。有個形象的比喻：HTTP是轎車，提供了封裝或者顯示數據的具體形式；Socket是發動機，提供了網絡通信的能力。
任何語言，都會提供對通訊的支持，我們今天用Java語言，演示幾種在Java中比較常用的通訊技術，包括：Socket、Http、REST、Dubbo、Thrift、FTP。
# Socket
**SocketServer.java**
~~~
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class SocketServer {
public static void main(String[] args) {
SocketServer ss = new SocketServer();
//設定服務端的端口號
ServerSocket s = null;
try {
s = new ServerSocket(10099);
System.out.println("ServerSocket Start:"+s);
while(true)
{
Socket socket = s.accept(); //這個地方是阻塞的
System.out.println("Server_Accept:"+socket);
SocketServer.HandleSocket vsm = ss.new HandleSocket(socket);
new Thread(vsm).start();
}
} catch (IOException e) {
e.printStackTrace();
} finally
{
try {
s.close();
} catch (IOException e) {
}
}
}
class HandleSocket implements Runnable
{
private Socket socket;
public HandleSocket(Socket socket)
{
this.socket = socket;
}
@Override
public void run() {
BufferedReader br = null;
PrintWriter pw = null;
try {
//用于接收客戶端發來的請求
br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
//用于發送返回信息,可以不需要裝飾這么多io流使用緩沖流時發送數據要注意調用.flush()方法
pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
String str = br.readLine();
if(str != null)
{
pw.println("OK_"+Thread.currentThread().getName());
pw.flush();
System.out.println("Command:"+str);
}
} catch (Exception e) {
e.printStackTrace();
}finally{
System.out.println("Server_Close:"+socket);
try {
br.close();
pw.close();
socket.close();
} catch (Exception e2) {
}
}
}
}
}
~~~
**SocketClient.java**
~~~
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
public class SocketClient {
public static void main(String[] args) throws InterruptedException {
for(int i=0;i<10;i++) {
call( "Hello" + i);
}
}
public static void call(String command) {
Socket socket = null;
BufferedReader br = null;
PrintWriter pw = null;
try {
//客戶端socket指定服務器的地址和端口號
socket = new Socket("127.0.0.1", 10099);
System.out.println("Client_Open" + socket + " Command:" + command);
//同服務器原理一樣
br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())));
pw.println(command);
pw.flush();
String str = br.readLine();
System.out.println("Client_Receive:"+str);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
System.out.println("Client_Close："+socket);
br.close();
pw.close();
socket.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
~~~
# Http
### **HttpConnection演示**
~~~
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpConnectionTest {
public static void main(String[] args) throws Exception {
System.out.println("begin send");
String inputParam = "<?xml version=\"1.0\" encoding=\"UTF-8\"?><content>Test</content></page>";
URL url = null;
HttpURLConnection httpConn = null;
OutputStream output = null;
OutputStreamWriter outr = null;
//url = new URL("http://127.0.0.1:8888/iotest/ReadServlet");
url = new URL("http://www.baidu.com");
httpConn = (HttpURLConnection) url.openConnection();
httpConn.setConnectTimeout(30000);
httpConn.setReadTimeout(30000);
HttpURLConnection.setFollowRedirects(true);
httpConn.setDoOutput(true);
httpConn.setRequestMethod("POST");
httpConn.setRequestProperty("Content-Type", "text/xml");
httpConn.connect();
output = httpConn.getOutputStream();
outr = new OutputStreamWriter(output);
// 寫入請求參數
outr.write(inputParam.toString().toCharArray(), 0, inputParam.toString().length());
outr.flush();
outr.close();
System.out.println("send ok");
int code = httpConn.getResponseCode();
System.out.println("code " + code);
System.out.println(httpConn.getResponseMessage());
//讀取響應內容
String sCurrentLine = "";
String sTotalString = "";
if (code == 200)
{
java.io.InputStream is = httpConn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
while ((sCurrentLine = reader.readLine()) != null)
if (sCurrentLine.length() > 0)
sTotalString = sTotalString + sCurrentLine.trim();
} else
{
sTotalString = "遠程服務器連接失敗,錯誤代碼:" + code;
}
System.out.println("response:" + sTotalString);
}
}
~~~
### **Apache HttpComponents**
官網：[http://hc.apache.org/](http://hc.apache.org/)
已經廢棄的Jar（這個項目，自從2007年8月份就不再維護了，已經遷移到org.apache.httpcomponents了）：
~~~
<dependency>
<groupId>commons-httpclient</groupId>
<artifactId>commons-httpclient</artifactId>
<version>3.1</version>
</dependency>
~~~
org.apache.httpcomponents maven依賴：
~~~
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore</artifactId>
<version>4.2.3</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.2.3</version>
</dependency>
~~~
Apache HttpComponents代碼演示：
~~~
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.KeyStore;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpException;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.CoreConnectionPNames;
import org.apache.http.params.HttpParams;
import com.creditease.ns.oltp.tunneladapter.tunnels.cb.util.CbConst;
/**
* 更多參考網址：http://hc.apache.org/
*
*/
public class HttpClientTest {
static String url = "http://www.tuicool.com/";
public static void main(String[] args) throws HttpException, IOException {
testHttp2();
}
public static void testHttp2() {
org.apache.http.client.HttpClient httpClient = null;
HttpPost httpPost = null;
InputStream in = null;
httpClient = new DefaultHttpClient();
httpPost = new HttpPost(url);
String resp = "";
try {
httpClient = new DefaultHttpClient();
httpPost = new HttpPost(url);
if (url.indexOf("https") != -1) {
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
in = new FileInputStream("quick.keystore");
keyStore.load(in, "chinabank".toCharArray());
SSLSocketFactory sslSocketFactory = new SSLSocketFactory(keyStore);
Scheme scheme = new Scheme("https", 443, sslSocketFactory);
httpClient.getConnectionManager().getSchemeRegistry().register(scheme);
}
HttpParams httpParams = httpClient.getParams();
httpParams.setIntParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 1000 * 20);
httpParams.setIntParameter(CoreConnectionPNames.SO_TIMEOUT, 1000 * 40);
List<NameValuePair> reqPair = new ArrayList<NameValuePair>();
reqPair.add(new BasicNameValuePair("charset", "UTF-8"));
reqPair.add(new BasicNameValuePair("req", "nihao"));
UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(reqPair, "UTF-8");
httpPost.setEntity(urlEncodedFormEntity);
HttpResponse response = httpClient.execute(httpPost);
HttpEntity responseEntity = response.getEntity();
if (responseEntity != null) {
InputStream is = responseEntity.getContent();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int ch = 0;
while ((ch = is.read(buffer)) != -1) {
baos.write(buffer, 0, ch);
}
byte bytes[] = baos.toByteArray();
resp = new String(bytes, CbConst.ENCODING);
}
int statusCode = response.getStatusLine().getStatusCode();
System.out.println("statusCode：" + statusCode);
System.out.println("resp：" + resp);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (in != null) {
in.close();
}
httpPost.releaseConnection();
httpClient.getConnectionManager().shutdown();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
~~~
quick.keystore，是一個密碼保護的文件，存放私鑰和證書。可以通過JDK自帶的keytool工具生成。只要有密碼，可以提取出私鑰和證書。參考網址：
[從Java Keystore文件中提取私鑰、證書](http://blog.csdn.net/moreorless/article/details/4985940)[](#)
[keystore提取私鑰和證書](http://blog.csdn.net/madun/article/details/8677783)
[java 調用 keytool 生成keystore 和 cer 證書](http://blog.csdn.net/saindy5828/article/details/11987587)
[KeyStore中的別名](http://blog.csdn.net/peterwanghao/article/details/1771723)
### 一個Http壓測例程
~~~
import java.io.BufferedReader;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map.Entry;
import java.util.Timer;
import java.util.TimerTask;
import java.util.UUID;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class HttpSocketPressTest {
private Long succNum = 0L;
private Long failNum = 0L;
private Long connFailNum = 0L;
private Long readFailNum = 0L;
private Long otherFailNum = 0L;
private Long beginTime = System.currentTimeMillis();
private Boolean recordSuccReturn = false;
private String url = "http://www.baidu.com";
public static final int ThreadNum = 100;
public static final int MonitorInterval = 3;
public static void main(String[] args) throws Exception {
createDir("d:\\httptest\\");
createDir("d:\\httptest\\succ\\");
createDir("d:\\httptest\\fail\\");
createDir("d:\\httptest\\exec\\");
createDir("d:\\httptest\\execother\\");
HttpSocketPressTest hspt = new HttpSocketPressTest();
if ((args != null) && (args.length > 0)) {
hspt.setRecordSuccReturn(true);
}
System.out.println("開" + ThreadNum + "個線程，測試用使用Socket5[10.100.140.85:1080]代理Get方式訪問外網。");
System.out.println("如果需要對200返回也記錄返回內容，請運行程序時輸入任意參數，記錄位置d:/httptest/succ。");
System.out.println("異常及非200返回會寫在d:/httptest/exception和fail目錄。");
ExecutorService executorService = Executors.newFixedThreadPool(ThreadNum);
for (int i = 0; i < ThreadNum; i++) {
executorService.submit(new HttpConn(hspt));
}
Monitor m = new Monitor(hspt);
Timer timer = new Timer();
timer.schedule(m, MonitorInterval * 1000, MonitorInterval * 1000);
}
public synchronized void IncreaseSuccNum() {
succNum++;
}
public synchronized void IncreaseFailNum() {
failNum++;
}
public synchronized void IncreaseConnFailNum() {
connFailNum++;
}
public synchronized void IncreaseReadFailNum() {
readFailNum++;
}
public synchronized void IncreaseOtherFailNum() {
otherFailNum++;
}
public synchronized Long getSuccNum() {
return succNum;
}
public synchronized Long getFailNum() {
return failNum;
}
public synchronized Long getConnFailNum() {
return connFailNum;
}
public synchronized Long getReadFailNum() {
return readFailNum;
}
public synchronized Long getOtherFailNum() {
return otherFailNum;
}
public Long getBeginTime() {
return beginTime;
}
public void setRecordSuccReturn(Boolean b) {
recordSuccReturn = b;
}
public Boolean getRecordSuccReturn() {
return recordSuccReturn;
}
public String getUrl() {
return url;
}
private static void createDir(String dir) {
File f = new File(dir);
if (!f.exists()) {
f.mkdir();
}
}
}
class Monitor extends TimerTask {
private HttpSocketPressTest hspt;
private Long times = 0L;
public Monitor(HttpSocketPressTest hspt) {
this.hspt = hspt;
}
@Override
public void run() {
Long nowTime = System.currentTimeMillis();
Long interval = nowTime - hspt.getBeginTime();
System.out.println("");
System.out.println("間隔" + HttpSocketPressTest.MonitorInterval + "秒報告一次結果，這是第" + ++times + "次，如下：");
System.out.println("當前時間：" + new Date());
System.out.println("累計運行時間（單位秒）：" + (interval / 1000));
System.out.println("成功次數：" + hspt.getSuccNum() + "；平均每秒成功次數：" + ((hspt.getSuccNum() * 1000) / interval));
System.out.println("失敗次數：" + hspt.getFailNum() + "【Connection timed out：" + hspt.getConnFailNum()
+ "，Read timed out：" + hspt.getReadFailNum() + "，其他異常：" + hspt.getOtherFailNum() + "】");
}
}
class HttpConn implements Runnable {
private HttpSocketPressTest hspt;
public HttpConn(HttpSocketPressTest hspt) {
this.hspt = hspt;
}
@Override
public void run() {
while (true) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd-HHmmss");
String d = sdf.format(new Date());
// System.out.println("[" + d + "] [" + Thread.currentThread().getName() +
// "] [訪問外網]");
// long startTime = System.currentTimeMillis();
String strUrl = hspt.getUrl();
String domainName = strUrl.split("\\.")[1];
HttpURLConnection httpConn = null;
BufferedReader reader = null;
try {
URL url = null;
url = new URL(strUrl);
Proxy p;
p = new Proxy(Proxy.Type.SOCKS, new InetSocketAddress("10.100.140.85", 1080));
httpConn = (HttpURLConnection) url.openConnection(p);
httpConn.setConnectTimeout(30 * 1000);
httpConn.setReadTimeout(30 * 1000);
HttpURLConnection.setFollowRedirects(true);
httpConn.setDoOutput(true);
httpConn.setRequestMethod("GET");
httpConn.setRequestProperty("Content-Type", "text/xml");
for (Entry<String, List<String>> m : httpConn.getHeaderFields().entrySet()) {
// System.out.println(m.getKey() + ":" + m.getValue());
}
// 這行代碼會報：java.net.ConnectException: Connection timed out: connect
httpConn.connect();
int code = httpConn.getResponseCode();
// 讀取響應內容
String sCurrentLine = "";
StringBuilder sb = new StringBuilder();
if (code == 200) {
hspt.IncreaseSuccNum();
} else {
hspt.IncreaseFailNum();
}
sb.append("StatusCode:").append(code).append("\n");
sb.append("url:").append(strUrl).append("\n");
InputStream is = httpConn.getInputStream();
reader = new BufferedReader(new InputStreamReader(is));
// 這行代碼會報：java.net.SocketTimeoutException: Read timed out
while ((sCurrentLine = reader.readLine()) != null) {
if (sCurrentLine.length() > 0) {
sb.append(sCurrentLine.trim());
}
}
// System.out.println("接收內容大小:" + sb.toString().length());
if (hspt.getRecordSuccReturn() && (code == 200)) {
writeFile("d:\\httptest\\succ\\" + d + "_" + UUID.randomUUID() + ".html", sb.toString());
}
if (code != 200) {
writeFile("d:\\httptest\\fail\\" + d + "_" + UUID.randomUUID() + ".html", sb.toString());
}
} catch (Exception e) {
e.printStackTrace();
System.out.println(new Date());
hspt.IncreaseFailNum();
String msg = e.toString();
Boolean isOther = false;
if (msg.indexOf("Connection timed out") != -1) {
hspt.IncreaseConnFailNum();
} else if (msg.indexOf("Read timed out") != -1) {
hspt.IncreaseReadFailNum();
} else {
isOther = true;
hspt.IncreaseOtherFailNum();
}
if (isOther) {
writeFile("d:\\httptest\\execother\\" + domainName + "_" + d + "_" + UUID.randomUUID() + ".txt", strUrl
+ "\r\n" + e);
} else {
writeFile("d:\\httptest\\exec\\" + domainName + "_" + d + "_" + UUID.randomUUID() + ".txt", strUrl + "\r\n"
+ e);
}
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (httpConn != null) {
httpConn.disconnect();
}
// System.out.println("[" + d + "] [" + Thread.currentThread().getName()
// + "] [訪問外網] [cost:["
// + (System.currentTimeMillis() - startTime) + "ms]]");
}
}
}
private void writeFile(String name, String content) {
FileWriter writer = null;
try {
// 打開一個寫文件器，構造函數中的第二個參數true表示以追加形式寫文件
writer = new FileWriter(name, false);
writer.write(content);
writer.close();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (writer != null) {
try {
writer.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
~~~
# Dubbo
...待續
# Thrift
...待續
# Rest
...待續
# FTP
...待續
- 前言
- Java之旅--如何從草根成為技術專家
- 《深入理解Java虛擬機》學習筆記
- 《Spring3.X企業應用開發實戰》學習筆記--IoC和AOP
- 《Tomcat權威指南》第二版學習筆記
- Java之旅--多線程進階
- Java之旅--Web.xml解析
- 《Spring3.X企業應用開發實戰》學習筆記--DAO和事務
- 《Spring3.X企業應用開發實戰》學習筆記--SpringMVC
- Java之旅--定時任務(Timer、Quartz、Spring、LinuxCron)
- Spring實用功能--Profile、WebService、緩存、消息、ORM
- JDK框架簡析--java.lang包中的基礎類庫、基礎數據類型
- JDK框架簡析--java.util包中的工具類庫
- JDK框架簡析--java.io包中的輸入輸出類庫
- Java之旅--通訊
- Java之旅--XML/JSON
- Java之旅--Linux&amp;java進階（看清操作系統層面的事）
- Java之旅--硬件和Java并發（神之本源）
- Java之旅--設計模式
- jetty