exists file java_java 中File类的exists()方法

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileWriter;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.MalformedURLException;

import java.net.URL;

import ch.unifr.article.util.Constant;

public class ReadInformation {

/**

* @param args

*/

private InputStream l_urlStream;

private FileWriter fw;

private String coding = "UTF-8";

public String getUrlText(String s) {

String text = "";

String sCurrentLine = "";

try {

URL url = new URL(s);

java.net.HttpURLConnection l_connection = (java.net.HttpURLConnection) url

.openConnection();

l_connection.connect();

l_urlStream = l_connection.getInputStream();

java.io.InputStreamReader read = new InputStreamReader(l_urlStream,

coding);

java.io.BufferedReader l_reader = new java.io.BufferedReader(read);

while ((sCurrentLine = l_reader.readLine()) != null) {

text += sCurrentLine;

}// viewSource(url);

} catch (MalformedURLException ex) {

System.out.println("网络连接错误:" + s);

ex.printStackTrace();

} catch (FileNotFoundException e) {

System.out.println("文件不存在:" + s);

e.printStackTrace();

} catch (IOException e) {

System.out.println("其他IO错误:" + s);

e.printStackTrace();

}

return text;

}

public static void main(String[] args) {

ReadInformation ri = new ReadInformation();

String url = "http://xxxx.com/sss.txt";//此处请lz填写txt地址

System.out.println(ri.getUrlText(url));

}

}