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一、使用tcp协议实现client向server发送数据
//TCP编程例一：客户端给服务端发送信息。服务端输出此信息到控制台上
//网络编程实际上就是Socket的编程
public class TestTCP1 {
// 客户端
@Test
public void client() {
Socket socket = null;
OutputStream os = null;
try {
// 1.创建一个Socket的对象，通过构造器指明服务端的IP地址，以及其接收程序的端口号
socket = new Socket(InetAddress.getByName("127.0.0.1"), 9090);
// 2.getOutputStream()：发送数据，方法返回OutputStream的对象
os = socket.getOutputStream();
// 3.具体的输出过程
os.write("我是客户端，请多关照".getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
// 4.关闭相应的流和Socket对象
if (os != null) {
try {
os.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
// 服务端
@Test
public void server() {
ServerSocket ss = null;
Socket s = null;
InputStream is = null;
try {
// 1.创建一个ServerSocket的对象，通过构造器指明自身的端口号
ss = new ServerSocket(9090);
// 2.调用其accept()方法，返回一个Socket的对象
s = ss.accept();
// 3.调用Socket对象的getInputStream()获取一个从客户端发送过来的输入流
is = s.getInputStream();
// 4.对获取的输入流进行的操作
byte[] b = new byte[20];
int len;
while ((len = is.read(b)) != -1) {
String str = new String(b, 0, len);
System.out.print(str);
}
System.out.println("收到来自于" + s.getInetAddress().getHostAddress()
+ "的连接");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
// 5.关闭相应的流以及Socket、ServerSocket的对象
if (is != null) {
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (s != null) {
try {
s.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (ss != null) {
try {
ss.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}二、在一的基础上实现server向client返回数据
//TCP编程例二：客户端给服务端发送信息，服务端将信息打印到控制台上，同时发送“已收到信息”给客户端
public class TestTCP2 {
//客户端
@Test
public void client(){
Socket socket = null;
OutputStream os = null;
InputStream is = null;
try {
socket = new Socket(InetAddress.getByName("127.0.0.1"),8989);
os = socket.getOutputStream();
os.write("我是客户端".getBytes());
//shutdownOutput():执行此方法，显式的告诉服务端发送完毕！
socket.shutdownOutput();
is = socket.getInputStream();
byte[] b = new byte[20];
int len;
while((len = is.read(b)) != -1){
String str = new String(b,0,len);
System.out.print(str);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(is != null){
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(os != null){
try {
os.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(socket != null){
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
//服务端
@Test
public void server(){
ServerSocket ss = null;
Socket s = null;
InputStream is = null;
OutputStream os = null;
try {
ss = new ServerSocket(8989);
s = ss.accept();
is = s.getInputStream();
byte[] b = new byte[20];
int len;
while((len = is.read(b)) != -1){
String str = new String(b,0,len);
System.out.print(str);
}
os = s.getOutputStream();
os.write("我已收到你的情意".getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(os != null){
try {
os.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(is != null){
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(s != null){
try {
s.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(ss != null){
try {
ss.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}三、使用流，client向server发送文件
//TCP编程例三：从客户端发送文件给服务端，服务端保存到本地。并返回“发送成功”给客户端。并关闭相应的连接。
//如下的程序，处理异常时，要使用try-catch-finally!!本例仅为了书写方便~
public class TestTCP3 {
@Test
public void client()throws Exception{
//1.创建Socket的对象
Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9898);
//2.从本地获取一个文件发送给服务端
OutputStream os = socket.getOutputStream();
FileInputStream fis = new FileInputStream(new File("1.jpg"));
byte[] b = new byte[1024];
int len;
while((len = fis.read(b)) != -1){
os.write(b,0,len);
}
socket.shutdownOutput();
//3.接收来自于服务端的信息
InputStream is = socket.getInputStream();
byte[] b1 = new byte[1024];
int len1;
while((len1 = is.read(b1)) != -1){
String str = new String(b1,0,len1);
System.out.print(str);
}
//4.关闭相应的流和Socket对象
is.close();
os.close();
fis.close();
socket.close();
}
@Test
public void server() throws Exception{
//1.创建一个ServerSocket的对象
ServerSocket ss = new ServerSocket(9898);
//2.调用其accept()方法，返回一个Socket的对象
Socket s = ss.accept();
//3.将从客户端发送来的信息保存到本地
InputStream is = s.getInputStream();
FileOutputStream fos = new FileOutputStream(new File("3.jpg"));
byte[] b = new byte[1024];
int len;
while((len = is.read(b)) != -1){
fos.write(b, 0, len);
}
System.out.println("收到来自于" + s.getInetAddress().getHostAddress() + "的文件");
//4.发送"接收成功"的信息反馈给客户端
OutputStream os = s.getOutputStream();
os.write("你发送的图片我已接收成功！".getBytes());
//5.关闭相应的流和Socket及ServerSocket的对象
os.close();
fos.close();
is.close();
s.close();
ss.close();
}
}