Alugg's Blog
0%

java-Day14——网络

发表于 分类于
本文字数： 3.7k 阅读时长 ≈ 3 分钟

InetAddress的使用

作用

InetAddress类的一个实例就代表一个具体的ip地址

实例化方式

InetAddress getByName(String host):获取指定ip对应的InetAddress的实例

InetAddress getLocalHost():获取本地ip对应的InetAddress的实例

常用方法

getHostName():

getHostAddress()

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
public class netTest {
    @Test
    public void test(){
    try{
        //1.实例化
        //getByName(String host):获取指定ip对应的InetAddress的实例
        InetAddress inet1 = InetAddress.getByName("192.168.23.31");
        System.out.println(inet1);

        InetAddress inet2 = InetAddress.getByName("www.baidu.com");
        System.out.println(inet2);

        //getLocalHost():获取本地Ip对应的InetAddress的实例
        InetAddress inet3 = InetAddress.getLocalHost();
        System.out.println(inet3);

        //2.两个常用方法
        System.out.println(inet1.getHostName());
        System.out.println(inet1.getHostAddress());

    }catch (UnknownHostException e){
            e.printStackTrace();
        }

    }
}

Socket类

TCP

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
public class TCPTest2 {
    @Test
    public void client(){
        Socket socket = null;
        FileInputStream fis = null;
        OutputStream os = null;
        try {
            //1.创建Socket
            InetAddress inetAddress = InetAddress.getByName("127.0.0.1");
            int port = 9090;
            socket = new Socket(inetAddress, port);
            //2.创建File的实例、FileInputStream的实例
            File file = new File("xx.jpg");
            fis = new FileInputStream(file);
            //3.通过Socket获取输出流
            os = socket.getOutputStream();
            //读写数据
            byte[] buffer = new byte[1024];
            int len;
            while ((len=fis.read(buffer))!=-1){
                os.write(buffer,0,len);
            }
            //4.接收来自于服务端的数据
            InputStream is = socket.getInputStream();
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            byte[] buffer1 = new byte[5];
            int len1;
            while((len1 = is.read(buffer))!=-1){
                baos.write(buffer1,0,len);
            }
            System.out.println(baos.toString());
            //客户端不再继续发送数据
            socket.shutdownOutput();

        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {
            //5.关闭Socket和相关流
            try {
                os.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            try {
                fis.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            try {
                socket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

    }

    @Test
    public void server(){
        ServerSocket serverSocket = null;
        Socket socket = null;
        InputStream is = null;
        FileOutputStream fos = null;
        try {
            //创建ServerSocket
            int port = 9090;
            serverSocket = new ServerSocket();
            //2.接受来自于客户端的socket：accept(_
            socket = serverSocket.accept();
            //3.通过Socket获取一个输入流
            is = socket.getInputStream();
            //4.创建File类的实例、FileOutputStream
            File file = new File("xxx_copy.jpg");
            fos = new FileOutputStream(file);
            //5.读写过程
            byte[] buffer = new byte[1024];
            int len;
            while((len = is.read(buffer))!=-1){
                fos.write(buffer, 0, len);
            }
            //6.服务端发送数据给客户端
            OutputStream os = socket.getOutputStream();
            os.write("pic recevied".getBytes());

        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {
            //6关闭相关Socket和流
            try {
                fos.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            try {
                is.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            try {
                socket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            try {
                serverSocket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

    }
}

URL

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
public class UrlTest {
    @Test
    public void test(){
        String str = "http://www.google.com";
        try {
            URL url = new URL(str);

            System.out.println(url.getProtocol());
            System.out.println(url.getHost());
            System.out.println(url.getPort());
            System.out.println(url.getFile());

        } catch (MalformedURLException e) {
            throw new RuntimeException(e);
        }
    }
}
-------------本文结束感谢您的阅读-------------