package com.gu.file;
import java.io.File;
//相对路径与绝对路径构建file对象
public class Demo1 {
public static void main(String[] args) {
//String path="E:"+File.pathSeparator+"";
String parentPath="E";
String name="2.txt";
//相对
File f=new File(parentPath, name);
System.out.println(f.getName());
//在当前路径下构建文件
f=new File("test.txt");
System.out.println(f.getName());
System.out.println(f.getAbsolutePath());
//绝对路径
f=new File("E:/test2");
System.out.println(f.getAbsolutePath());
}
}
package com.gu.file;
import java.io.File;
import java.io.FilenameFilter;
import java.util.Arrays;
/**
* 输出目录下文件
* @author 谷
*
*/
public class Demo2 {
public static void main(String[] args) {
String path="E:/test";
File parent =new File(path);
//printName(parent);
//printFiles(parent);
File []roots=File.listRoots();
System.out.println(Arrays.toString(roots));
}
//递归显示所有子文件和文件夹
public static void printFiles(File src){
if(src==null||!src.exists()){
return ;
}
System.out.println(src.getAbsolutePath());
if(src.isDirectory()){
for(File f:src.listFiles()){
printFiles(f);
}
}
}
//递归显示所有子文件
public static void printName(File src){
getdric(src);
File []files=src.listFiles(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return new File(dir, name).isDirectory();
}
});
for(File ff:files){
//System.out.println(ff.getAbsolutePath());
printName(ff);
}
}
//获取当前目录下的子文件夹
public static void getdric(File src){
if(src==null||!src.exists()){
return ;
}
if(src.isDirectory()){
for(File f:src.listFiles(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return new File(dir, name).isFile();
}
})){
System.out.println(f.getAbsolutePath());
src=f;
}
}
package com.gu.stream;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
/**
* 字节缓冲流无新增方法,但提高性能
* 字符缓冲流有reader.readLine(),write.newLine（）；
* 例如：String line=null;
* while(null!=(line=bufferedreader.readline))
* 替换：char[]in=new char[1024];
* int len=0;
* while(-1!=(len=reader.read(in)))
* @author 谷
*
*/
public class filecopyUtil {
public static void main(String[] args) {
File src=new File ("E:/test/dd/Demo1.txt");
File dest=new File ("E:/test/");
try {
copyFile(src, dest);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void copyFile(String srcPath,String destpath) throws IOException {
copyFile(new File (srcPath),new File(destpath));
}
public static void copyFile(File src,File dest) throws IOException ,FileNotFoundException{
if(!src.isFile()){
System.out.print("不是文件");
throw new IOException("只能拷贝文件");
}
if(src==null||!src.exists()){
return ;
}
BufferedInputStream in=new BufferedInputStream(new FileInputStream(src));
//OutputStream out=new FileOutputStream(dest);
BufferedOutputStream out=new BufferedOutputStream(new FileOutputStream(dest));
//BufferedOutputStream ，BufferedInputStream 无新增方法
byte[]car=new byte[10];
int len;
while(-1!=(len=in.read(car))){
out.write(car, 0, len);
}
out.flush();
in.close();
out.close();
}
}
}
}
