Java 下載 HTTP 資源儲存到本地
阿新 • • 發佈：2019-01-07
最近做個新功能，需要用到這個功能，測試無誤，發上來備忘 :)
package com.xxx.utility;
/*******************************************************************************
* <p>Title: xxx</p> * <p>Description: xxx</p> * <p>Copyright: Copyright (c) 2006 DavidHsing All Rights Reserved</p> * <p>Company: xxx</p> * * @author : DavidHsing <DavidHsing(At)163.com> * @version : 1.00 * @date : 2007-08-28 * @direction: 下載 HTTP 網路資源儲存到本地
******************************************************************************/import java.io.*;import java.net.*;//******************************************************************************publicclass HttpDownload{ //========================================================================== //public HttpDownload() {} //========================================================================== private Vector vRemoteHttpURL =new Vector(); private Vector vLocalSaveFile =new Vector(); //==========================================================================
/**
* 設定代理伺服器 * @param String * @param String
*/ publicvoid setProxy(String sProxyHost, String sProxyPort) { if (sProxyHost !=null&&!sProxyHost.trim().equals("")) { if (sProxyPort ==null|| sProxyPort.trim().equals("")) { sProxyPort ="80"; } System.getProperties().put("proxySet", "true"); System.getProperties().put("proxyHost", sProxyHost); System.getProperties().put("proxyPort", sProxyPort); } } //========================================================================== /** * 新增一個下載任務 * @param String * @param String * @return boolean */ publicboolean addOneTask(String sRemoteHttpURL, String sLocalSaveFile) { if (sRemoteHttpURL ==null|| sRemoteHttpURL.trim().equals("") ||!sRemoteHttpURL.trim().substring(0, 7).equalsIgnoreCase("http://")) { System.out.println(" @> HttpDownload.addOneTask() : 源地址有誤，不是一個有效的 http 地址！"); returnfalse; } else { if (sLocalSaveFile ==null|| sLocalSaveFile.trim().equals("")) { sLocalSaveFile ="./"+ sRemoteHttpURL.substring(sRemoteHttpURL.lastIndexOf("/") +1); } vRemoteHttpURL.add(sRemoteHttpURL); vLocalSaveFile.add(sLocalSaveFile); } returntrue; } //========================================================================== /** * 清除下載列表 */ publicvoid clearAllTasks() { vRemoteHttpURL.clear(); vLocalSaveFile.clear(); } //========================================================================== /** * 根據列表下載資源 * @return boolean */ publicboolean downLoadByList() { for (int i =0; i < vRemoteHttpURL.size(); i++) { String sRemoteHttpURL = (String)vRemoteHttpURL.get(i); String sLocalSaveFile = (String)vLocalSaveFile.get(i); if (!saveToFile(sRemoteHttpURL, sLocalSaveFile)) { System.out.println(" @> HttpDownload.downLoadByList() : 下載遠端資源時出現異常！"); //return false; } } returntrue; } //========================================================================== /** * 將 HTTP 資源儲存為檔案 * @param String * @param String * @return boolean */ privateboolean saveToFile(String sRemoteHttpURL, String sLocalSaveFile) { if (sRemoteHttpURL ==null|| sRemoteHttpURL.trim().equals("")) { System.out.println(" @> HttpDownload.saveToFile() : 要下載的遠端資源地址不能為空！"); returnfalse; } try { URL tURL =new URL(sRemoteHttpURL); HttpURLConnection tHttpURLConnection = (HttpURLConnection)tURL.openConnection(); tHttpURLConnection.connect(); BufferedInputStream tBufferedInputStream =new BufferedInputStream(tHttpURLConnection.getInputStream()); FileOutputStream tFileOutputStream =new FileOutputStream(sLocalSaveFile); int nBufferSize =1024*5; byte[] bufContent =newbyte[nBufferSize]; int nContentSize =0; while ((nContentSize = tBufferedInputStream.read(bufContent)) !=-1) { tFileOutputStream.write(bufContent, 0, nContentSize); } tFileOutputStream.close(); tBufferedInputStream.close(); tHttpURLConnection.disconnect(); tURL =null; tHttpURLConnection =null; tBufferedInputStream =null; tFileOutputStream =null; } catch (Exception ex) { System.out.println(" @> HttpDownload.saveToFile() : 下載遠端資源時出現異常！"); System.out.println(" 遠端地址："+ sRemoteHttpURL); System.out.println(" 本地路徑："+ sLocalSaveFile); returnfalse; }