我要把D盘的文件“aa.txt”复制到E盘上,求代码 代码会使用到输入流和输出流最好在这2个地方注释下,这个我还不太明白,谢谢了!javaOutputStream 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 File f=new File("d:\\aa.txt"); f.renameTo("e:\\aa.txt");//移动 f.delete();//删除 我靠,这么简单!能说下file函数和renameto函数吗? 不一定非得用流操作,方法多了。org.apache.commons.io.FileUtils.copyFileToDirectory("d:\\aa.txt", "e:\\", true);这一句就行了 class Test { public static void main(String args[]) { FileInputStream fis = null; FileOutputStream fos = null; byte[] buffer = new byte[100]; int temp = 0; try { fis = new FileInputStream("D:\\aa.txt"); fos = new FileOutputStream("E:\\aa.txt"); while (true) { temp = fis.read(buffer, 0, buffer.length); if (temp == -1) { break; } fos.write(buffer, 0, temp); } } catch (Exception e) { System.out.println(e); } finally { try { fis.close(); fos.close(); } catch (Exception e2) { System.out.println(e2); } } }} import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStreamReader;import java.io.OutputStreamWriter;public class CopyFile { public static void main(String[] args) throws Exception{ //输入流 File file = new File("d:\\aa.txt"); FileInputStream fs = new FileInputStream(file); InputStreamReader isr = new InputStreamReader(fs); BufferedReader br = new BufferedReader(isr); //输出流 File file_copy = new File("e:\\aa.txt"); FileOutputStream fos = new FileOutputStream(file_copy); OutputStreamWriter osw = new OutputStreamWriter(fos); BufferedWriter bw = new BufferedWriter(osw); String str = null; //读写aa.txt的内容 while((str = br.readLine())!=null){ bw.write(str + "\n"); } bw.flush(); bw.close(); }} temp = fis.read(buffer, 0, buffer.length);这句我不理解,求解释 temp = fis.read(buffer, 0, buffer.length);这句我不理解,求解释 从源文件中将最多 buffer.length个字节的数据读入一个 byte 数组中,并用一个int型的变量保存下来,以便用于在目标文件中写入这么多数据。fos.write(buffer, 0, temp); 既然LZ要操作的是文本文件,还是用Reader Writer吧import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;public class CopyFile { public static void main(String[] args) { BufferedReader bufr = null; BufferedWriter bufw = null; File file = new File("D:\\aa.txt"); try { if(!file.exists()) throw new FileNotFoundException("文件不存在"); bufr = new BufferedReader(new FileReader(file)); bufw = new BufferedWriter(new FileWriter("D:\\aa_copy.txt")); String line = null; while((line=bufr.readLine())!=null) { bufw.write(line); bufw.newLine(); bufw.flush(); } } catch (IOException e) { System.out.println(e.toString()); } finally { try { if(bufr!=null) bufr.close(); } catch (IOException e2) { throw new RuntimeException("文件读取流关闭失败"); } try { if(bufw!=null) bufw.close(); } catch (IOException e3) { throw new RuntimeException("文件写入流关闭失败"); } } }} 这句话的意思是,读buffer这个缓冲区,从哪开始读啊?从0开始读,把所以的都读出来 lz去下载个javase6.0_cn的中文api,学会看api org.apache.commons.io.FileUtils.copyFileToDirectory("d:\\aa.txt", "e:\\", true);这一句就行了 org.apache.commons.io.FileUtils.copyFileToDirectory("d:\\aa.txt", "e:\\", true);这一句就行了 急:关于HttpUrlConnection 各位达人帮帮忙! 在线等 菜鸟提问,高手帮帮忙 关于固有代码编译器的提问!!! jacob 打开excel问题 请问JDK帮助文档里面怎么没有Servlet的说明? 有没有JAVA操作注册表的例子啊 大家帮帮忙看看,好奇怪啊!谢了! 字符串转换为整数 决定每次提问给分的数量是由什么决定的???? HashMap扩容的这一步怎么理解 java 如何判断txt的编码字符集 java中打印返回值的问题
f.renameTo("e:\\aa.txt");//移动
f.delete();//删除
org.apache.commons.io.FileUtils.copyFileToDirectory("d:\\aa.txt", "e:\\", true);这一句就行了
public static void main(String args[]) {
FileInputStream fis = null;
FileOutputStream fos = null;
byte[] buffer = new byte[100];
int temp = 0;
try {
fis = new FileInputStream("D:\\aa.txt");
fos = new FileOutputStream("E:\\aa.txt");
while (true) {
temp = fis.read(buffer, 0, buffer.length);
if (temp == -1) {
break;
}
fos.write(buffer, 0, temp);
}
} catch (Exception e) {
System.out.println(e);
} finally {
try {
fis.close();
fos.close();
} catch (Exception e2) {
System.out.println(e2);
}
} }
}
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;public class CopyFile {
public static void main(String[] args) throws Exception{
//输入流
File file = new File("d:\\aa.txt");
FileInputStream fs = new FileInputStream(file);
InputStreamReader isr = new InputStreamReader(fs);
BufferedReader br = new BufferedReader(isr);
//输出流
File file_copy = new File("e:\\aa.txt");
FileOutputStream fos = new FileOutputStream(file_copy);
OutputStreamWriter osw = new OutputStreamWriter(fos);
BufferedWriter bw = new BufferedWriter(osw);
String str = null;
//读写aa.txt的内容
while((str = br.readLine())!=null){
bw.write(str + "\n");
}
bw.flush();
bw.close();
}
}
temp = fis.read(buffer, 0, buffer.length);这句我不理解,求解释
从源文件中将最多 buffer.length个字节的数据读入一个 byte 数组中,并用一个int型的变量保存下来,以便用于在目标文件中写入这么多数据。
fos.write(buffer, 0, temp);
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;public class CopyFile {
public static void main(String[] args)
{
BufferedReader bufr = null;
BufferedWriter bufw = null;
File file = new File("D:\\aa.txt");
try
{
if(!file.exists())
throw new FileNotFoundException("文件不存在");
bufr = new BufferedReader(new FileReader(file));
bufw = new BufferedWriter(new FileWriter("D:\\aa_copy.txt"));
String line = null;
while((line=bufr.readLine())!=null)
{
bufw.write(line);
bufw.newLine();
bufw.flush();
}
}
catch (IOException e)
{
System.out.println(e.toString());
}
finally
{
try
{
if(bufr!=null)
bufr.close();
}
catch (IOException e2)
{
throw new RuntimeException("文件读取流关闭失败");
}
try
{
if(bufw!=null)
bufw.close();
}
catch (IOException e3)
{
throw new RuntimeException("文件写入流关闭失败");
}
}
}
}