android 輔助工具類——文件簡單操作輔助類

爲了以後其他項目中方便使用，提取之前項目中的一些通用的類，分享給大家。該類爲文件簡單操作輔助類。

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * 文件簡單操作輔助類
 * @author 
 *
 */
public class FILE {
	/**
	 * 文件是否存在
	 * @param filePathName
	 * @return
	 */
	public static boolean isExist(String filePathName) {
		File file = new File(filePathName);
		return (!file.isDirectory() && file.exists());
	}
	
	public static boolean isDirExist(String filePathName) {
		if(!filePathName.endsWith("/")) filePathName +="/";
		File file = new File(filePathName);
		return (file.isDirectory() && file.exists());
	}
	
	/**
	 * 獲取路徑，不帶文件名，末尾帶'/'
	 * @param filePathName
	 * @return
	 */
	public static String getPath(String filePathName) {
		try {
			return filePathName.substring(0, filePathName.lastIndexOf('/') + 1);
		} catch (Exception e) {
			return "";
		}
	}
	
	/**
	 * 獲取目錄的名稱 注意：只能獲取如：/aaaa/ssss/ 或 /aaaa/dsddd
	 * @param filePathName
	 * @return
	 */
	public static String getDirPathName(String filePathName) {
		try {
			if(filePathName.endsWith("/"))
				filePathName = filePathName.substring(0, filePathName.lastIndexOf('/'));
			return filePathName.substring(filePathName.lastIndexOf("/") + 1, filePathName.length());
		} catch (Exception e) {
			return "";
		}
	}
	/**
	 * 獲取文件名，帶後綴
	 * @param filePathName
	 * @return
	 */
	public static String getName(String filePathName) {
		try {
			return filePathName.substring(filePathName.lastIndexOf('/') + 1);
		} catch (Exception e) {
			return "";
		}
	}
	
	/**
	 * 獲取文件名，不帶後綴
	 * @return
	 */
	public static String getNameNoPostfix(String filePathName) {
		try {
			return filePathName.substring(filePathName.lastIndexOf('/') + 1, filePathName.lastIndexOf('.'));
		} catch (Exception e) {
			return "";
		}
	}
	
	/**
	 * 重命名
	 * @param filePathName
	 * @param newPathName
	 */
	public static void rename(String filePathName, String newPathName) {
		if(isNullString(filePathName)) return ;
		if(isNullString(newPathName)) return ;
		
		FILE.delete(newPathName); //liuwp 20120830 新名稱對應的文件可能已經存在，先刪除
		
		File file = new File(filePathName);
		File newFile = new File(newPathName);
		file.renameTo(newFile);
	}
	
	/**
	 * 刪除文件
	 */
	public static void delete(String filePathName) {
		if(isNullString(filePathName)) return ;
 		File file = new File(filePathName);
		if (file.isFile() && file.exists()) {
			boolean flag = file.delete();
			LOG.I("LOG", "filePathName reset:"+filePathName+" flag:"+flag);
		}
	}
	
	/**
	 * 創建目錄，整個路徑上的目錄都會創建
	 * @param path
	 */
	public static void createDir(String path) {
		File file = new File(path);
		if (!file.exists()) {
			file.mkdirs();
		}
	}
	
	/** 嘗試創建空文件
	 * <br> 如果文件已經存在不操作,返回true
	 * @param path 路徑
	 * @return	如果創建失敗(Exception) 返回false，否則true
	 */
	public static boolean createEmptyFile(String path){
		File file = new File(path);
		if(!file.exists()){
			try{
				return file.createNewFile();
			}
			catch (Exception e) {
				return false;
			}
		}
		return true;
	}
	
	/**
	 * 獲取文件大小
	 * @param filePathName
	 * @return
	 */
	public static long getSize(String filePathName) {
		if(isNullString(filePathName)) return 0;
		File file = new File(filePathName);
		if (file.isFile()) return file.length();
		return 0;
	}
	
	/**
	 * 讀取文件數據到byte數組
	 * @param filePathName 文件名
	 * @param readOffset 從哪裏開始讀
	 * @param readLength 讀取長度
	 * @param dataBuf 保存數據的緩衝區
	 * @param bufOffset 從哪裏保存
	 * @return
	 */
	public static boolean readData(String filePathName, int readOffset, int readLength, byte[] dataBuf, int bufOffset) {
		try {
			int readedTotalSize = 0;
			int onceReadSize = 0;
			
			BufferedInputStream in = new BufferedInputStream(new FileInputStream(filePathName));
			in.skip(readOffset);
			while (readedTotalSize < readLength 
					&& (onceReadSize = in.read(dataBuf, bufOffset + readedTotalSize, readLength - readedTotalSize)) >= 0) {
				readedTotalSize += onceReadSize;
			}
			in.read(dataBuf, bufOffset, readLength);
			in.close();
			in = null;
		} catch (Exception e) {
			return false;
		}
		return true;
	}
	
	/** 將某個流的內容輸出到文件
	 * @param in 輸入流
	 * @param filePathName 目標文件
	 * @return 
	 */
	public static boolean writeFile(InputStream in,String filePathName){
		boolean flag = false;
		OutputStream outStream = null;
		try {
			File destFile = new File(filePathName);
			if (destFile.exists()) {
				destFile.delete();
			} else {
				destFile.createNewFile();
			}
			outStream = new FileOutputStream(filePathName);
			byte[] buffer = new byte[1024];
			int count = 0;
			while(true){
				int length = in.read(buffer, 0, 1024);
				if(length > 0){
					outStream.write(buffer, 0, length);
				}else{
					break;
				}
				count+=length;
			}
			if(count > 0){
				flag = true;
			}
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			if(outStream != null){
				try{outStream.close();}catch(Exception e){e.printStackTrace();}
			}
		}
		return flag;
	}
	
	/**
	 * 判斷當前字符串是否爲空
	 * @param str
	 * @return
	 */
	public static boolean isNullString(String str) {
		if(str == null || str.equals("")) return true ;
		return false;
	}
	
	/**
	 * 複製文件
	 * @param fromPathName
	 * @param toPathName
	 * @return
	 */
	public static int copy(String fromPathName, String toPathName) {
		try {
			InputStream from = new FileInputStream(fromPathName);
			return copy(from, toPathName);
		} catch (FileNotFoundException e) {
			return -1;
		}
	}
	
	/**
	 * 複製文件
	 * @param from
	 * @param toPathName
	 * @return
	 */
	public static int copy(InputStream from, String toPathName) {
		try {
			FILE.delete(toPathName); //liuwp 20120925 先刪除
			OutputStream to = new FileOutputStream(toPathName);
			byte buf[] = new byte[1024];
			int c;
			while ((c = from.read(buf)) > 0) {
				to.write(buf, 0, c);
			}
			from.close();
			to.close();
			return 0;
		} catch (Exception ex) {
			return -1;
		}
	}
	
	
	/**
	 * 根據zip文件路徑轉換爲文件路徑
	 *  @param zipFullPath 必須帶.zip
	 * @return
	 */
	public static String zip2FileFullPath(String zipFullPath) {
		int zipIndex = zipFullPath.lastIndexOf(".zip");
		int zipIndexTmp = zipFullPath.lastIndexOf(".ZIP");
		String tmp = "";
		if(zipIndex > -1) {
			tmp = zipFullPath.substring(0, zipIndex);
		} else if(zipIndexTmp > -1) {
			tmp = zipFullPath.substring(0, zipIndexTmp);
		}
		return tmp;
	}
	
	/**
	 * 改變文件權限
	 * @param permission
	 * @param filePathName
	 */
	public static void chmod(String permission, String filePathName)
	{
		try {
			String command = "chmod " + permission + " " + filePathName;
			Runtime runtime = Runtime.getRuntime();
			runtime.exec(command);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}