java网络编程入门到精通

public class NetTest {
/**设定缓存的属性**/
public static final String PROPERTY_NETCACHE = "networkaddress.cache.ttl";
/**异常信息缓存属性**/
public static final String PROPERTY_EXCEPTIONCACHE = "networkaddress.cache.negative.ttl";

public static void main(String[] args) throws IOException {
/*
* 初始化InetAddress host既可以是主机名也可以是ip地址 addr是以字节数组表示的ip地址
* 1:InetAddress.getByName(String host) 返回该主机所对应的第一个主机名/ip
* 2:InetAddress.getLocalHost() 返回本地主机 主机名/ip
* 3:InetAddress.getAllByName(String host) 返回该主机对应的所有 主机名/ip
* 4:InetAddress.getByAddress(byte[] addr) 返回 主机名/ip
* 5:InetAddress.getByAddress(String host, byte[] addr) 返回主机名/ip
*/
InetAddress ia = InetAddress.getByName("www.baidu.com");
out.println(ia);

InetAddress localIp = InetAddress.getLocalHost();
out.println(localIp);

InetAddress[] allIpAddress = InetAddress.getAllByName("www.google.com");
for (InetAddress address : allIpAddress){
System.out.println(address);
}

InetAddress byAddress = InetAddress.getByAddress(new byte[]{74,125,71,103});
out.println(byAddress);

InetAddress byHostAddress = InetAddress.getByAddress("www.baidu.com", new byte[]{119,75,218-256,45});
out.println(byHostAddress);
/*
* 设置缓存超时 单位秒 -1表示一直缓存
* 设置了缓存机制，第二次访问该dns服务器就直接读缓存
*/
Security.setProperty(PROPERTY_NETCACHE, "-1");
/*
* 设置异常信息缓存秒数
*/
Security.setProperty(PROPERTY_EXCEPTIONCACHE, "10");
//判断能否连接
System.out.println(ia.isReachable(100));
/*
* 获取ip字符串
*/
out.println(ia.getHostAddress());
/*
* 获取该ip地址的主机别名 InetAddress由ip创建 返回主机名
*/
out.println(ia.getHostName());
/*
* 获取该ip地址的主机名
*/
out.println(ia.getCanonicalHostName());
/*
* 获取字节数组组成的ip地址
*/
out.println(ia.getAddress());
/*
* 使用ip创建的InetAddressgetHostName()才访问服务器
*/
out.println(byAddress.getHostName());
/*
* Mire字符串的转换
* URLDecoder 特殊---->一般 URLEncoder 一般---->特殊
*/
//解码
String keyWord = URLDecoder.decode("%E8%8D%89%E6%B3%A5%E9%A9%AC", "UTF-8");
out.println(keyWord);
//编码
String keyWordd = URLEncoder.encode(keyWord, "UTF-8");
out.println(keyWordd);
}
}