filehelper.java

一个java编写的下载器源码

package com.leapget.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * 对本地文件进行操作
 * 
 * @author  0501xql
 * @date    2008-8-4
 * @version 1.0
 */
public class FileHelper {

	// 新建一个临时文件
	public static File getTempFile(String filePath){
		File file = new File(filePath + "_tmp.xql");
		return file;
	}
	// 合并临时文件
	public static void uniteFile(String tmpFile) {
		try {
			new File(tmpFile+"_tmp.xql").renameTo(new File(tmpFile));
			new File(tmpFile+"_ini.xql").delete();		// 配置文件
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	// 获得一个网络文件的大小
	public static int getFileLength(String fileUrl) {
		int len = -1;
		HttpURLConnection conn = null;
		try {
			conn = (HttpURLConnection) (new URL(fileUrl)).openConnection();
			len = conn.getContentLength();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if (conn != null)
				conn.disconnect();
		}
		return len;
	}
}