Java.Utils：网络工具包[通俗易懂]

大家好，又见面了，我是你们的朋友全栈君。

Don’t say much, just go to the code.

package org.bood.shimmer.common.utils;

import org.springframework.util.MultiValueMap;
import org.springframework.web.util.UriComponentsBuilder;

import javax.net.ssl.HttpsURLConnection;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.*;

/** * 网络工具包 * * @author bood * @since 2020/9/25 */
public class NetUtils { 
   

    private NetUtils() { 
   
    }


    /** * <p> * 获取请求中的 IP * </p> * * @param request: * @return：java.lang.String * @author：bood * @date：2020/9/25 */
    public static String getIpAddress(HttpServletRequest request) { 
   
        String[] ipHeaders = { 
   "x-forwarded-for", "Proxy-Client-IP", "WL-Proxy-Client-IP", "HTTP_CLIENT_IP", "HTTP_X_FORWARDED_FOR"};
        String[] localhostIp = { 
   "127.0.0.1", "0:0:0:0:0:0:0:1"};
        String ip = request.getRemoteAddr();
        for (String header : ipHeaders) { 
   
            if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) { 
   
                break;
            }
            ip = request.getHeader(header);
        }
        for (String local : localhostIp) { 
   
            if (ip != null && ip.equals(local)) { 
   
                try { 
   
                    ip = InetAddress.getLocalHost().getHostAddress();
                } catch (UnknownHostException ignored) { 
   
                }
                break;
            }
        }
        if (ip != null && ip.length() > 15 && ip.contains(",")) { 
   
            ip = ip.substring(0, ip.indexOf(','));
        }
        return ip;
    }

    /** * <p> * IP 转 Integer * </p> * * @param ip: IP 地址 * @return：java.lang.Integer * @author：bood * @date：2020/9/25 */
    public static Integer ipToInteger(String ip) { 
   
        String[] ips = ip.split("\\.");
        int ipFour = 0;
        for (String ip4 : ips) { 
   
            Integer ip4a = Integer.parseInt(ip4);
            ipFour = (ipFour << 8) | ip4a;
        }
        return ipFour;
    }

    /** * <p> * Integer 转 IP * </p> * * @param ip: IP 地址 * @return：java.lang.String * @author：bood * @date：2020/9/25 */
    public static String IntegerToIp(Integer ip) { 
   
        StringBuilder sb = new StringBuilder();
        for (int i = 3; i >= 0; i--) { 
   
            int ipa = (ip >> (8 * i)) & (0xff);
            sb.append(ipa + ".");
        }
        sb.delete(sb.length() - 1, sb.length());
        return sb.toString();
    }

    /** * <p> * IP 地址是否可达 * </p> * * @param ip: IP 地址 * @return：boolean * @author：bood * @date：2020/9/25 */
    public static boolean isReachable(String ip) { 
   
        InetAddress address;
        try { 
   
            address = InetAddress.getByName(ip);
            if (address.isReachable(5000)) { 
   
                return true;
            }
        } catch (IOException e) { 
   
            e.printStackTrace();
        }
        return false;
    }

    /** * <p> * 根据 url 和请求参数获取 URI * </p> * * @param url: 请求地址 * @param params: 请求参数 * @return：java.net.URI * @author：bood * @date：2020/9/25 */
    public static URI getURIwithParams(String url, MultiValueMap<String, String> params) { 
   
        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(url).queryParams(params);
        return builder.build().encode().toUri();
    }

    /** * <p> * 判断网址是否有效 * 对于404页面，如果被电信或者联通劫持了，也会返回200的状态，这个是不准确的 * </p> * * @param url: 请求地址 * @return：boolean * @author：bood * @date：2020/9/25 */
    public static boolean isReachable(URL url) { 
   
        boolean reachable = false;
        HttpURLConnection httpconn = null;
        HttpsURLConnection httpsconn = null;
        int code = 0;

        try { 
   
            if ("https".equals(url.getProtocol())) { 
   
                httpsconn = (HttpsURLConnection) url.openConnection();
                code = httpsconn.getResponseCode();
            } else { 
   
                httpconn = (HttpURLConnection) url.openConnection();
                code = httpconn.getResponseCode();
            }
            if (code == 200) { 
   
                reachable = true;
            }
        } catch (Exception e) { 
   
            reachable = false;
        }

        return reachable;
    }

    /** * <p> * 实现 Ping 命令 * Ping 的字符串换行使用 java 的换行符"\n"，如果 ping 不同返回 null * </p> * * @param ip: IP 地址 * @return：java.lang.String * @author：bood * @date：2020/9/25 */
    public static String ping(String ip) { 
   
        String res = "";
        String line = null;
        try { 
   
            Process pro = Runtime.getRuntime().exec("ping " + ip);
            BufferedReader buf = new BufferedReader(new InputStreamReader(pro.getInputStream(), "GBK"));
            while ((line = buf.readLine()) != null) { 
   
                if (!"".equals(line)) { 
   
                    res += line + "\n";
                }
            }
        } catch (Exception e) { 
   
            res = null;
        }
        return res;
    }

}