前言：
時下互聯網第一波的浪潮已消逝，隨著而來的基於千萬數據的物聯網時代，因而數據成為企業的重要戰略資源之一。基於資料抓取技術，本文介紹了java相關抓取工具，並附上demo原始碼供有興趣的朋友測試！
1）JDK自備HTTP連接，取得頁面或Json
2） JDK自帶URL連接，取得頁面或Json
#3）HttpClient Get工具，取得頁面或Json
4）commons-io工具，取得頁面或Json
# 
5） Jsoup工具（通常用於html欄位解析），取得頁面,非Json返回格式】
#完整程式碼：
package com.yeezhao.common.http;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.URL;import org.apache.commons.httpclient.HttpClient;import org.apache.commons.httpclient.HttpMethod;import org.apache.commons.httpclient.methods.GetMethod;import org.apache.commons.io.IOUtils;import org.jsoup.Jsoup;/**
* http工具对比
*
* @author Administrator -> junhong
*
* 2016年12月27日 */public class HttpFetchUtil {
/**
* 获取访问的状态码
* @param request
* @return
* @throws Exception */
public static int getResponseCode(String request) throws Exception {
URL url = new URL(request);
HttpURLConnection conn = (HttpURLConnection) url.openConnection(); return conn.getResponseCode();
} /**
* 1）JDK自带HTTP连接，获取页面或Json
* @param request
* @param charset
* @return
* @throws Exception */
public static String JDKFetch(String request, String charset) throws Exception {
URL url = new URL(request);
HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //模拟浏览器参数
conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36"
+ " (KHTML, like Gecko) Chrome/45.0.2454.101 Safari/537.36"); if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
InputStream input = conn.getInputStream();
StringBuffer sb = new StringBuffer();
BufferedReader reader = new BufferedReader(new InputStreamReader(input, charset));
String s; while ((s = reader.readLine()) != null) {
sb.append(s + "\n");
}
input.close();
conn.disconnect(); return sb.toString();
} return "";
} /**
* 2） JDK自带URL连接，获取页面或Json
* @param request
* @param charset
* @return
* @throws Exception */
public static String URLFetch(String request, String charset) throws Exception {
URL url = new URL(request); return IOUtils.toString(url.openStream());
} /**
* 3）HttpClient Get工具，获取页面或Json
* @param url
* @param charset
* @return
* @throws Exception */
public static String httpClientFetch(String url, String charset) throws Exception { // GET
HttpClient httpClient = new HttpClient();
httpClient.getParams().setContentCharset(charset);
HttpMethod method = new GetMethod(url);
httpClient.executeMethod(method); return method.getResponseBodyAsString();
} /**
* 4）commons-io工具，获取页面或Json
* @param url
* @param charset
* @return
* @throws Exception */
public static String commonsIOFetch(String url, String charset) throws Exception { return IOUtils.toString(new URL(url), charset);
}
/**
* 5） Jsoup工具（通常用于html字段解析），获取页面,非Json返回格式
* @param url
* @return
* @throws Exception */
public static String jsoupFetch(String url) throws Exception { return Jsoup.parse(new URL(url), 2 * 1000).html();
}
}登入後複製
测试代码：
package com.yeezhao.common.http;import org.junit.After;import org.junit.Before;import org.junit.Test;/**
* 测试类
* 3个测试链接：
* 1）百科网页
* 2）浏览器模拟获取接口数据
* 3）获取普通接口数据
* @author Administrator -> junhong
*
* 2016年12月27日 */public class HttpFetchUtilTest {
String seeds[] = {"http://baike.baidu.com/view/1.htm","http://m.ximalaya.com/tracks/26096131.json","http://remyapi.yeezhao.com/api/query?wd=%E5%91%A8%E6%98%9F%E9%A9%B0%E7%9A%84%E7%94%B5%E5%BD%B1"}; final static String DEFAULT_CHARSET = "UTF-8";
@Before public void setUp() throws Exception {
}
@After public void tearDown() throws Exception {
System.out.println("--- down ---");
}
@Test public void testGetResponseCode() throws Exception{ for(String seed:seeds){ int responseCode = HttpFetchUtil.getResponseCode(seed);
System.out.println("ret="+responseCode);
}
}
@Test public void testJDKFetch() throws Exception{ for(String seed:seeds){
String ret = HttpFetchUtil.JDKFetch(seed, DEFAULT_CHARSET);
System.out.println("ret="+ret);
}
}
@Test public void testURLFetch() throws Exception{ for(String seed:seeds){
String ret = HttpFetchUtil.URLFetch(seed, DEFAULT_CHARSET);
System.out.println("ret="+ret);
}
}
@Test public void testHttpClientFetch()throws Exception { for(String seed:seeds){
String ret = HttpFetchUtil.httpClientFetch(seed, DEFAULT_CHARSET);
System.out.println("ret="+ret);
}
}
@Test public void testCommonsIOFetch()throws Exception { for(String seed:seeds){
String ret = HttpFetchUtil.commonsIOFetch(seed, DEFAULT_CHARSET);
System.out.println("ret="+ret);
}
}
@Test public void testJsoupFetch() throws Exception{ for(String seed:seeds){
String ret = HttpFetchUtil.jsoupFetch(seed);
System.out.println("ret="+ret);
}
}
}登入後複製
附：相关jar依赖
...<dependency>
<groupid>org.jsoup</groupid>
<artifactid>jsoup</artifactid>
<version>1.7.3</version>
</dependency>
<dependency>
<groupid>commons-httpclient</groupid>
<artifactid>commons-httpclient</artifactid>
<version>3.1</version>
</dependency>
<dependency>
<groupid>commons-io</groupid>
<artifactid>commons-io</artifactid>
<version>2.4</version>
</dependency>...
登入後複製
后语：
现在的数据时代，有着"数据即财富"的理念。因此，数据抓取技术将一直发展更新，基于此后续还将扩充针对POST方法的抓取方式，敬请期待！
以上是http資料抓取Java實作的幾種方式的詳細內容。更多資訊請關注PHP中文網其他相關文章！
