如何將下載的java源代碼導(dǎo)入到eclipse中運(yùn)行

eclipse打開并運(yùn)行一個已經(jīng)寫好的java文件步驟如下：

1、新建一個java工程項(xiàng)目：右鍵Eclipse的PackageExplorer空白部分，點(diǎn)擊New，再點(diǎn)擊JavaProject，輸入工程名，點(diǎn)擊finish；

2、在新建的工程里新建一個類：右鍵工程，點(diǎn)擊New，再點(diǎn)擊Class，輸入類名，點(diǎn)擊finish；

3、把寫好的java文件的代碼復(fù)制到新建的類中；

4、右鍵新建的類文件，點(diǎn)擊RunAs，再點(diǎn)擊JavaApplication即可運(yùn)行Java文件。

需要注意的是：java文件要成功運(yùn)行，前提是要有主方法（main）的存在，沒有主方法沒辦法運(yùn)行java程序。

Java文件下載怎么實(shí)現(xiàn)的

下載就很簡單了

把你要下載的文件做成超級鏈接，可以不用任何組件

比如說

下載一個word文檔

a href="名稱.doc"名稱.doc/a

路徑你自己寫

import java.io.File;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.io.InputStream;

import java.io.RandomAccessFile;

import java點(diǎn)虐.HttpURLConnection;

import java點(diǎn)虐.ProtocolException;

import java點(diǎn)虐.URI;

import java點(diǎn)虐.URL;

import java.util.Random;

/**

*

* 實(shí)現(xiàn)了下載的功能*/

public class SimpleTh {

public static void main(String[] args){

// TODO Auto-generated method stub

//String path = "倩女幽魂.mp3";//MP3下載的地址

String path ="";

try {

new SimpleTh().download(path, 3); //對象調(diào)用下載的方法

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static String getFilename(String path){//獲得文件的名字

return path.substring(path.lastIndexOf('/')+1);

}

public void download(String path,int threadsize) throws Exception//下載的方法

{//參數(shù) 下載地址，線程數(shù)量

URL url = new URL(path);

HttpURLConnection conn = (HttpURLConnection)url.openConnection();//獲取HttpURLConnection對象

conn.setRequestMethod("GET");//設(shè)置請求格式，這里是GET格式

conn.setReadTimeout(5*1000);//

int filelength = conn.getContentLength();//獲取要下載文件的長度

String filename = getFilename(path);

File saveFile = new File(filename);

RandomAccessFile accessFile = new RandomAccessFile(saveFile, "rwd");

accessFile.setLength(filelength);

accessFile.close();

int block = filelength%threadsize ==0?filelength/threadsize:filelength/threadsize+1;

for(int threadid = 0;threadid=threadsize;threadid++){

new DownloadThread(url,saveFile,block,threadid).start();

}

}

private final class DownloadThread extends Thread{

private URL url;

private File saveFile;

private int block;//每條線程下載的長度

private int threadid;//線程id

public DownloadThread(URL url,File saveFile,int block,int threadid){

this.url = url;

this.saveFile= saveFile;

this.block = block;

this.threadid = threadid;

}

@Override

public void run() {

//計(jì)算開始位置的公式：線程id*每條線程下載的數(shù)據(jù)長度=？

//計(jì)算結(jié)束位置的公式：（線程id+1）*每條線程下載數(shù)據(jù)長度-1=？

int startposition = threadid*block;

int endposition = (threadid+1)*block-1;

try {

try {

RandomAccessFile accessFile = new RandomAccessFile(saveFile, "rwd");

accessFile.seek(startposition);//設(shè)置從什么位置寫入數(shù)據(jù)

HttpURLConnection conn = (HttpURLConnection)url.openConnection();

conn.setRequestMethod("GET");

conn.setReadTimeout(5*1000);

conn.setRequestProperty("Range","bytes= "+startposition+"-"+endposition);

InputStream inStream = conn.getInputStream();

byte[]buffer = new byte[1024];

int len = 0;

while((len = inStream.read(buffer))!=-1){

accessFile.write(buffer, 0, len);

}

inStream.close();

accessFile.close();

System.out.println("線程id："+threadid+"下載完成");

} catch (FileNotFoundException e) {

e.printStackTrace();

}

} catch (IOException e) {

e.printStackTrace();

}

}

}

}

Java 下載文件的方法怎么寫

參考下面

public HttpServletResponse download(String path, HttpServletResponse response) {

try {

// path是指欲下載的文件的路徑。

File file = new File(path);

// 取得文件名。

String filename = file.getName();

// 取得文件的后綴名。

String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();

// 以流的形式下載文件。

InputStream fis = new BufferedInputStream(new FileInputStream(path));

byte[] buffer = new byte[fis.available()];

fis.read(buffer);

fis.close();

// 清空response

response.reset();

// 設(shè)置response的Header

response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));

response.addHeader("Content-Length", "" + file.length());

OutputStream toClient = new BufferedOutputStream(response.getOutputStream());

response.setContentType("application/octet-stream");

toClient.write(buffer);

toClient.flush();

toClient.close();

} catch (IOException ex) {

ex.printStackTrace();

}

return response;

}

// 下載本地文件

public void downloadLocal(HttpServletResponse response) throws FileNotFoundException {

String fileName = "Operator.doc".toString(); // 文件的默認(rèn)保存名

// 讀到流中

InputStream inStream = new FileInputStream("c:/Operator.doc");// 文件的存放路徑

// 設(shè)置輸出的格式

response.reset();

response.setContentType("bin");

response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");

// 循環(huán)取出流中的數(shù)據(jù)

byte[] b = new byte[100];

int len;

try {

while ((len = inStream.read(b)) 0)

response.getOutputStream().write(b, 0, len);

inStream.close();

} catch (IOException e) {

e.printStackTrace();

}

}

// 下載網(wǎng)絡(luò)文件

public void downloadNet(HttpServletResponse response) throws MalformedURLException {

int bytesum = 0;

int byteread = 0;

URL url = new URL("windine.blogdriver點(diǎn)抗/logo.gif");

try {

URLConnection conn = url.openConnection();

InputStream inStream = conn.getInputStream();

FileOutputStream fs = new FileOutputStream("c:/abc.gif");

byte[] buffer = new byte[1204];

int length;

while ((byteread = inStream.read(buffer)) != -1) {

bytesum += byteread;

System.out.println(bytesum);

fs.write(buffer, 0, byteread);

}

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

//支持在線打開文件的一種方式

public void downLoad(String filePath, HttpServletResponse response, boolean isOnLine) throws Exception {

File f = new File(filePath);

if (!f.exists()) {

response.sendError(404, "File not found!");

return;

}

BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));

byte[] buf = new byte[1024];

int len = 0;

response.reset(); // 非常重要

if (isOnLine) { // 在線打開方式

URL u = new URL("" + filePath);

response.setContentType(u.openConnection().getContentType());

response.setHeader("Content-Disposition", "inline; filename=" + f.getName());

// 文件名應(yīng)該編碼成UTF-8

} else { // 純下載方式

response.setContentType("application/x-msdownload");

response.setHeader("Content-Disposition", "attachment; filename=" + f.getName());

}

OutputStream out = response.getOutputStream();

while ((len = br.read(buf)) 0)

out.write(buf, 0, len);

br.close();

out.close();

}

java 下載文件

package?needlnotify;

import?java.io.*;

import?java點(diǎn)虐.*;

public?class?HomeWorkMyself2?{

????public?static?void?main(String...?args)?throws?IOException?{

????????download(new?URL(args[0]),?new?FileOutputStream(args[1])?);

????}

????/**

?????*?JDK?7?風(fēng)格的下載代碼

[email protected]

?????*/

????static?private?void?download(URL?url,OutputStream?out)?throws?IOException?{

????????byte[]?buf?=?new?byte[8096];

????????int?r;

????????try(?InputStream??ins?=?url.openStream()?)?{

????????????while((?r=ins.read(buf))!=-1?)?

????????????????out.write(buf,0,r);

????????}

????}

}