这样新建文件为何不行? FileWriter fw=new FileWriter(folderPath + "/'"+tempName+"'");FileWriter fw=new FileWriter(folderPath + "/"+tempName);你是调试的时候走到这里就结束了,还是运行的时候? 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 我认为:import java.io.*;public class FileTest{ public static void main(String[] args){ String tempName="c.txt"; File file = new File(".",tempName);try{ //file.createNewFile(); String folderPath ="export"; FileWriter fw = new FileWriter(folderPath + "\\"+ tempName); }catch(Exception e){ System.out.println("e"); } }}我试验了一下,得出如下结论:1。如果你当前文件夹下存在export目录,那么new FileWriter时就会在该目录下,创建一个新的文件2。如果不存在export目录,那么就抛出异常。因此你应该保证当前目录下存在export目录,否则,你应该先创建该目录。 给你个实例,相信可以帮到你.package com.io;import java.io.File;import java.io.IOException;import java.io.FileWriter;import java.io.BufferedWriter;import java.util.Date;import java.text.SimpleDateFormat;/** * Created by IntelliJ IDEA. * User: heyj * Date: 2003/09/03 * Time: 13:56:55 * To change this template use Options | File Templates. */public class FileTest { /** * create txt file by current date+time * @param String _fileName * @return boolean * @throws IOException */ public boolean ctFile(String _path, String _fileName) throws IOException { boolean success = false; String fileName = _fileName; String filePath = _path; try { File file = new File(filePath); if (!file.isDirectory()) { file.mkdirs(); } File f = new File(filePath + File.separator + fileName + ".txt"); success = f.createNewFile(); } catch (IOException e) { e.printStackTrace(); } return success; } /** * write string into specify file * @param _fileName * @throws IOException */ public void writeFile(String _path, String _fileName) throws IOException { try { BufferedWriter out = new BufferedWriter(new FileWriter(_path + File.separator + _fileName + ".txt")); out.write("this is a test string!"); out.newLine(); out.flush(); BufferedWriter appOut = new BufferedWriter(new FileWriter(_path + File.separator + _fileName + ".txt", true)); appOut.write("this string is append str"); appOut.flush(); out.close(); } catch (IOException e) { e.printStackTrace(); } } public static void main(String args[]) { SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMddHHmmss"); String fileName = formatter.format(new Date()); FileTest b = new FileTest(); try { //create file boolean succ = b.ctFile("c:\\aa\\bb", fileName); System.out.println("create file success:" + succ); //write file b.writeFile("c:\\aa\\bb", fileName); System.out.println("write file success!"); } catch (IOException e) { e.printStackTrace(); } }} 希望大家与我交流.msn:[email protected] java打包以后在另一台电脑上能打开,但是连不上数据库,十万火急,13号要交作业 关于字节流读中文的问题,抛分了啊 JTextField问题 自动聚焦(在线等) GUI 设计 菜鸟socket问题 为什么不能添加记录?? JAVA 语法 菜鸟求指导 类型转换 下周靠SCWCD,给我一点力量吧! 在JAVA中经常有*.jar文件,请问有什么用?可以打开吗? 如何使图的画填上填充上clolor?我的代码是。。。 列表读取的一个简单问题。请教
import java.io.*;
public class FileTest{
public static void main(String[] args){
String tempName="c.txt"; File file = new File(".",tempName);
try{
//file.createNewFile(); String folderPath ="export"; FileWriter fw = new FileWriter(folderPath + "\\"+ tempName);
}catch(Exception e){
System.out.println("e");
}
}}我试验了一下,得出如下结论:
1。如果你当前文件夹下存在export目录,那么new FileWriter时就会在该目录下,创建一个新的文件
2。如果不存在export目录,那么就抛出异常。
因此你应该保证当前目录下存在export目录,否则,你应该先创建该目录。
package com.io;import java.io.File;
import java.io.IOException;
import java.io.FileWriter;
import java.io.BufferedWriter;
import java.util.Date;
import java.text.SimpleDateFormat;/**
* Created by IntelliJ IDEA.
* User: heyj
* Date: 2003/09/03
* Time: 13:56:55
* To change this template use Options | File Templates.
*/
public class FileTest { /**
* create txt file by current date+time
* @param String _fileName
* @return boolean
* @throws IOException
*/
public boolean ctFile(String _path, String _fileName) throws IOException {
boolean success = false;
String fileName = _fileName;
String filePath = _path;
try {
File file = new File(filePath);
if (!file.isDirectory()) {
file.mkdirs();
}
File f = new File(filePath + File.separator + fileName + ".txt");
success = f.createNewFile(); } catch (IOException e) {
e.printStackTrace();
}
return success; } /**
* write string into specify file
* @param _fileName
* @throws IOException
*/
public void writeFile(String _path, String _fileName) throws IOException { try {
BufferedWriter out = new BufferedWriter(new FileWriter(_path + File.separator + _fileName + ".txt"));
out.write("this is a test string!");
out.newLine();
out.flush();
BufferedWriter appOut = new BufferedWriter(new FileWriter(_path + File.separator + _fileName + ".txt", true)); appOut.write("this string is append str");
appOut.flush();
out.close();
} catch (IOException e) {
e.printStackTrace();
} } public static void main(String args[]) { SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMddHHmmss");
String fileName = formatter.format(new Date()); FileTest b = new FileTest();
try {
//create file
boolean succ = b.ctFile("c:\\aa\\bb", fileName);
System.out.println("create file success:" + succ); //write file
b.writeFile("c:\\aa\\bb", fileName);
System.out.println("write file success!"); } catch (IOException e) {
e.printStackTrace();
} }}