Java 发送HTTP或HTTPS请求获取网页码源（1）

闲来无事，封装了一个简单的工具类，用于向某个URL发送请求并获取响应的文本内容。发送HTTP请求的方式比较简单，但用来发送HTTPS请求却不行的。 于是查了一些资料，根据前人经验写了这个工具类，能够区分URL是HTTP类型还是HTTPS类型的，但对HTTPS方式的原理的研究尚浅，也只是拿来便用。 因为是工具类，所有方法均为static修饰，但只对外部提供了getSourceFromUrl(String url,String charsetName) 和 getSourceFromUrl(String url) 两个重载的方法，第一个可以按指定编码读取流。 码源如下，JDK1.7下测试通过，仅使用JDK提供的Jar包： import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.security.SecureRandom; import java.security.cert.CertificateException; import java.security.cert.X509Certificate; import javax.net.ssl.HttpsURLConnection; import javax.net.ssl.SSLContext; import javax.net.ssl.SSLSocketFactory; import javax.net.ssl.TrustManager; import javax.net.ssl.X509TrustManager; /** * 通用工具类 * 更新：2016-12-3 16:13:27 * 版本：1.0.0 */ public final class CommonNetUtil { //默认编码 private final static String CHARSETNAME = "UTF-8"; //协议类型 private final static String HTTP = "http:"; private final static String HTTPS = "https:"; /** * 判断协议类型，转发到不同的方法进行处理 * @throws IOException */ private static String chooseProtocol(String url,String charsetName) throws IOException{ if (url == null) { throw new RuntimeException("url shouldn't be null."); } //字符编码格式 if (charsetName == null){ throw new NullPointerException("charsetName shouldn't be null."); } if (!url.startsWith(HTTP) && !url.startsWith(HTTPS)) { throw new RuntimeException("url format is not supported."); } //如果是http协议 if (url.startsWith(HTTP)) { return getFromHttp(url,charsetName); }else if (url.startsWith(HTTPS)) { //如果是https协议 return getFromHttps(url, charsetName); } return null; } /** * http协议的url * @param url * @param charsetName * @return * @throws IOException */ private static String getFromHttp(String url,String charsetName) throws IOException{ HttpURLConnection con = null; try { // 打开网页 con = (HttpURLConnection) new URL(url).openConnection(); con.connect(); //判断状态码 if (con.getResponseCode() == 200) { //读取流 return getTextFromCon(con,charsetName); } } catch (IOException e) { throw new IOException("Connet exception.", e); } finally { if (con != null) { con.disconnect(); } } return null; } /** * https协议的url * @param url * @param charsetName * @return * @throws IOException */ private static String getFromHttps(String url,String charsetName) throws IOException{ HttpsURLConnection httpsConn = null; try { //构造TrustManager 对象数组 TrustManager[] tm = {new X509TrustManager() { @Override public X509Certificate[] getAcceptedIssuers() { return null; } @Override public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException { } @Override public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException { } }}; //创建SSLContext对象，并使用我们指定的信任管理器初始化 SSLContext sslContext = SSLContext.getInstance("SSL","SunJSSE"); sslContext.init(null, tm, new SecureRandom()); //从上述SSLContext对象中得到SSLSocketFactory对象 SSLSocketFactory ssf = sslContext.getSocketFactory(); //创建HttpsURLConnection对象，并设置其SSLSocketFactory对象 httpsConn = (HttpsURLConnection)new URL(url).openConnection(); httpsConn.setSSLSocketFactory(ssf); //连接 httpsConn.connect(); //判断状态码 if (httpsConn.getResponseCode() == 200) { //读取流 return getTextFromCon(httpsConn,charsetName); } } catch (Exception e) { throw new IOException("Connet exception.", e); }finally{ if (httpsConn != null) { httpsConn.disconnect(); } } return null; } /** * 从流中读取数据 * @param con * @param charsetName * @return * @throws IOException */ private static String getTextFromCon(URLConnection con,String charsetName) throws IOException{ StringBuffer sb = new StringBuffer(); try( BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream(),charsetName)); ) { String s = null; while ((s = br.readLine()) != null) { //sb.append(s); //不换行 sb.append(s + "\n"); //换行 } return sb.toString(); } catch (IOException e) { throw new IOException("Read stream exception.", e); } } /** * 根据URL获取码源 * @param url * @return 返回字符串型码源 * @throws IOException */ public static String getSourceFromUrl(String url) throws IOException { return chooseProtocol(url, CHARSETNAME); } /** * 根据URL获取码源，可指定用何种编码进行解码 * @param url * @param charsetName 编码类型 * @return 返回字符串型码源 * @throws IOException */ public static String getSourceFromUrl(String url,String charsetName) throws IOException { return chooseProtocol(url, charsetName); } }

测试类：

import java.io.IOException; /* 测试类*/ public class Test { public static void main(String[] args) { String url = "https://www.baidu.com"; try { String content= CommonNetUtil.getSourceFromUrl(url); System.out.println(content); } catch (IOException e) { e.printStackTrace(); } } }

结果：

记录到此。

发送HTTPS请求参考了此文，http://blog.csdn.net/lifj07/article/details/8638098，表示感谢。