Java 文件操作工具类详解编程语言

  
package util; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileOutputStream; 
import java.io.FilenameFilter; 
public class FileUtil { 
private final static String FILE_SUFFIX = ".java.drl"; 
private final static String FILE_TEMP = "C:/temp/"; 
/** 
* 将已存在的drl文件删除 
*  
* @param ObjectPath 
*/ 
public static void deleteExistedDRLFile(String ObjectPath) { 
File filePath = new File(ObjectPath); 
if (!filePath.exists()) { 
System.out.println("目录不存在!"); 
} else { 
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(new FilenameFilter() { 
public boolean accept(File dir, String name) { 
return name.endsWith(FILE_SUFFIX); 
} 
}); 
for (int i = 0; i < list.length; i++) { 
list[i].delete(); 
} 
} 
} 
} 
/** 
* 创建文件夹,如果有则不创建 
*  
* @param ObjectPath 
*/ 
public static boolean creareDirectory(String ObjectPath) { 
boolean flag = true; 
File filePath = new File(ObjectPath); 
if (!filePath.exists()) { 
filePath.mkdir(); 
flag = false; 
} 
return flag; 
} 
/** 
* 查看某文件夹下面是否有文件,有文件则创建一个temp文件夹,将文件拷贝到temp目录下(备份文件) 没有文件怎什么都不做 
* 备份后，把原文件夹里文件删除 
*  
* @param ObjectPath 
*/ 
public static void backupFile(String ObjectPath, String dirName) { 
String backupPath; 
if (!FILE_TEMP.endsWith(File.separator)) { 
backupPath = FILE_TEMP + File.separator + dirName; 
} else { 
backupPath = FILE_TEMP + dirName; 
} 
File backupFilePath = new File(backupPath); 
if (!backupFilePath.exists()) { 
backupFilePath.mkdirs(); 
} 
File filePath = new File(ObjectPath); 
if (!filePath.exists()) { 
System.out.println("目录不存在!"); 
} else { 
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(); 
if (list != null && list.length != 0) { 
copyFolder(ObjectPath, backupPath);// 文件备份 
for (int i = 0; i < list.length; i++) { 
list[i].delete(); 
} 
} 
} 
} 
} 
/** 
* 复原文件，把文件从备份文件夹拷贝到原来文件夹 
*  
* @param ObjectPath 
* @param dirName 
*/ 
public static void recoverFile(String ObjectPath, String dirName) { 
String backupPath; 
if (ObjectPath.endsWith(File.separator)) { 
ObjectPath = new StringBuffer(ObjectPath).append(dirName) 
.toString(); 
} else { 
ObjectPath = new StringBuffer(ObjectPath) 
.append(File.separatorChar).append(dirName).toString(); 
} 
if (!FILE_TEMP.endsWith(File.separator)) { 
backupPath = FILE_TEMP + File.separator + dirName; 
} else { 
backupPath = FILE_TEMP + dirName; 
} 
File backupFilePath = new File(backupPath); 
if (!backupFilePath.exists()) { 
backupFilePath.mkdirs(); 
} 
File filePath = new File(ObjectPath); 
if (!filePath.exists()) { 
System.out.println("目录不存在!"); 
} else { 
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(); 
if (list != null && list.length != 0) { 
copyFolder(backupPath, ObjectPath);// 文件复原 
} 
} 
} 
} 
/** 
* 复制整个文件夹内容 
*  
* @param oldPath 
*            String 原文件路径 如：c:/fqf 
* @param newPath 
*            String 复制后路径 如：f:/fqf/ff 
* @return boolean 
*/ 
public static void copyFolder(String oldPath, String newPath) { 
try { 
(new File(newPath)).mkdir(); // 如果文件夹不存在 则建立新文件夹 
File a = new File(oldPath); 
String[] file = a.list(); 
File temp = null; 
for (int i = 0; i < file.length; i++) { 
if (oldPath.endsWith(File.separator)) { 
temp = new File(oldPath + file[i]); 
} else { 
temp = new File(oldPath + File.separator + file[i]); 
} 
if (temp.isFile()) { 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream(newPath 
+ "/" + (temp.getName()).toString()); 
byte[] b = new byte[1024 * 5]; 
int len; 
while ((len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
} 
if (temp.isDirectory()) {// 如果是子文件夹 
copyFolder(oldPath + "/" + file[i], newPath + "/" + file[i]); 
} 
} 
} catch (Exception e) { 
System.out.println("复制整个文件夹内容操作出错"); 
e.printStackTrace(); 
} 
} 
/** 
* 删除备份文件和存放备份文件的文件夹 
*  
* @param ObjectPath 
*/ 
public static void deleteFileAndDirectory(String dirName) { 
String ObjectPath; 
if (!FILE_TEMP.endsWith(File.separator)) { 
ObjectPath = FILE_TEMP + File.separator + dirName; 
} else { 
ObjectPath = FILE_TEMP + dirName; 
} 
File filePath = new File(ObjectPath); 
if (!filePath.exists()) { 
filePath.mkdirs(); 
System.out.println("目录不存在!"); 
} else { 
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(); 
for (int i = 0; i < list.length; i++) { 
list[i].delete(); 
} 
} 
filePath.delete(); 
} 
} 
/** 
* 判断某文件夹下是否存在文件，存在返回true 
*  
* @param ObjectPath 
* @return 
*/ 
public static boolean existFileInDirectory(String ObjectPath) { 
boolean flag = false; 
File filePath = new File(ObjectPath); 
if (filePath.exists()) { 
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(); 
if (list != null && list.length != 0) { 
flag = true; 
} 
} 
} 
return flag; 
} 
/** 
* 删除某个文件夹 
* @param ObjectPath 
*/ 
public static void deleteDirectory(String ObjectPath) { 
File filePath = new File(ObjectPath); 
if (filePath.exists()) { 
filePath.delete(); 
} 
} 
/** 
* 将已存在的文件删除 
*  
* @param ObjectPath 
*/ 
public static boolean deleteExistedFile(String ObjectPath,final String fileName) { 
boolean flag =false; 
File filePath = new File(ObjectPath); 
if (filePath.exists()) {             
if (filePath.isDirectory()) { 
File[] list = filePath.listFiles(new FilenameFilter() { 
public boolean accept(File dir, String name) { 
return name.equals(fileName); 
} 
}); 
for (int i = 0; i < list.length; i++) { 
list[i].delete(); 
} 
flag=true; 
} 
} 
return flag; 
} 
}