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小编给大家分享一下超全文件工具类FileUtil的示例分析,相信大部分人都还不怎么了解,因此分享这篇文章给大家参考一下,希望大家阅读完这篇文章后大有收获,下面让我们一起去了解一下吧!
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1 我项目中用到的文件工具类
1 读取raw文件、file文件,drawable文件,asset文件,比如本地的json数据,本地文本等;
如:String result =FileUtil.getString(context,”raw://first.json”)
2 读取本地的property文件,并转化为hashMap类型的数据 (simpleProperty2HashMap);
3 将raw文件拷贝到指定目录(copyRawFile);
4 基本文件读写操作(readFile,writeFile);
5 从文件的完整路径名(路径+文件名)中提取 路径(extractFilePath);
6 从文件的完整路径名(路径+文件名)中提取文件名(包含扩展名)
如:d:\path\file.ext –> file.ext(extractFileName)
7 检查指定文件的路径是否存在(pathExists)
8 检查制定文件是否存在(fileExists)
9 创建目录(makeDir)
10 移除字符串中的BOM前缀(removeBomHeaderIfExists)
package com.nsu.edu.library.utils; import android.content.Context; import android.graphics.Bitmap; import android.graphics.drawable.BitmapDrawable; import android.text.TextUtils; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; 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.InputStreamReader; import java.io.OutputStream; import java.util.HashMap; import java.util.Iterator; import java.util.Properties; import java.util.Set; /** * Create By Anthony on 2016/1/15 * Class Note:文件工具类 * 包含内容: * 1 读取raw文件、file文件,drawable文件,asset文件,比如本地的json数据,本地文本等; * 如:String result =FileUtil.getString(context,"raw://first.json") * 2 读取本地的property文件,并转化为hashMap类型的数据(simpleProperty2HashMap); * 3 将raw文件拷贝到指定目录(copyRawFile); * 4 基本文件读写操作(readFile,writeFile); * 5 从文件的完整路径名(路径+文件名)中提取 路径(extractFilePath); * 6 从文件的完整路径名(路径+文件名)中提取文件名(包含扩展名) 如:d:\path\file.ext --> file.ext(extractFileName) *7 检查指定文件的路径是否存在(pathExists) *8 检查制定文件是否存在(fileExists) *9 创建目录(makeDir) *10 移除字符串中的BOM前缀(removeBomHeaderIfExists) */ public class FileUtil { public static final String ASSETS_PREFIX = "file://android_assets/"; public static final String ASSETS_PREFIX2 = "file://android_asset/"; public static final String ASSETS_PREFIX3 = "assets://"; public static final String ASSETS_PREFIX4 = "asset://"; public static final String RAW_PREFIX = "file://android_raw/"; public static final String RAW_PREFIX2 = "raw://"; public static final String FILE_PREFIX = "file://"; public static final String DRAWABLE_PREFIX = "drawable://"; public static InputStream getStream(Context context, String url) throws IOException { String lowerUrl = url.toLowerCase(); InputStream is; if (lowerUrl.startsWith(ASSETS_PREFIX)) { String assetPath = url.substring(ASSETS_PREFIX.length()); is = getAssetsStream(context, assetPath); } else if (lowerUrl.startsWith(ASSETS_PREFIX2)) { String assetPath = url.substring(ASSETS_PREFIX2.length()); is = getAssetsStream(context, assetPath); } else if (lowerUrl.startsWith(ASSETS_PREFIX3)) { String assetPath = url.substring(ASSETS_PREFIX3.length()); is = getAssetsStream(context, assetPath); } else if (lowerUrl.startsWith(ASSETS_PREFIX4)) { String assetPath = url.substring(ASSETS_PREFIX4.length()); is = getAssetsStream(context, assetPath); } else if (lowerUrl.startsWith(RAW_PREFIX)) { String rawName = url.substring(RAW_PREFIX.length()); is = getRawStream(context, rawName); } else if (lowerUrl.startsWith(RAW_PREFIX2)) { String rawName = url.substring(RAW_PREFIX2.length()); is = getRawStream(context, rawName); } else if (lowerUrl.startsWith(FILE_PREFIX)) { String filePath = url.substring(FILE_PREFIX.length()); is = getFileStream(filePath); } else if (lowerUrl.startsWith(DRAWABLE_PREFIX)) { String drawableName = url.substring(DRAWABLE_PREFIX.length()); is = getDrawableStream(context, drawableName); } else { throw new IllegalArgumentException(String.format("Unsupported url: %s \n" + "Supported: \n%sxxx\n%sxxx\n%sxxx", url, ASSETS_PREFIX, RAW_PREFIX, FILE_PREFIX)); } return is; } private static InputStream getAssetsStream(Context context, String path) throws IOException { return context.getAssets().open(path); } private static InputStream getFileStream(String path) throws IOException { return new FileInputStream(path); } private static InputStream getRawStream(Context context, String rawName) throws IOException { int id = context.getResources().getIdentifier(rawName, "raw", context.getPackageName()); if (id != 0) { try { return context.getResources().openRawResource(id); } catch (Exception e) { e.printStackTrace(); } } throw new IOException(String.format("raw of id: %s from %s not found", id, rawName)); } private static InputStream getDrawableStream(Context context, String rawName) throws IOException { int id = context.getResources().getIdentifier(rawName, "drawable", context.getPackageName()); if (id != 0) { BitmapDrawable drawable = (BitmapDrawable) context.getResources().getDrawable(id); Bitmap bitmap = drawable.getBitmap(); ByteArrayOutputStream os = new ByteArrayOutputStream(); bitmap.compress(Bitmap.CompressFormat.PNG, 0, os); return new ByteArrayInputStream(os.toByteArray()); } throw new IOException(String.format("bitmap of id: %s from %s not found", id, rawName)); } public static String getString(Context context, String url) throws IOException { return getString(context, url, "UTF-8"); } public static String getString(Context context, String url, String encoding) throws IOException { String result = readStreamString(getStream(context, url), encoding); if (result.startsWith("\ufeff")) { result = result.substring(1); } return result; } public static String readStreamString(InputStream is, String encoding) throws IOException { return new String(readStream(is), encoding); } public static byte[] readStream(InputStream is) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buf = new byte[1024 * 10]; int readlen; while ((readlen = is.read(buf)) >= 0) { baos.write(buf, 0, readlen); } baos.close(); return baos.toByteArray(); } public static Bitmap getDrawableBitmap(Context context, String rawName) { int id = context.getResources().getIdentifier(rawName, "drawable", context.getPackageName()); if (id != 0) { BitmapDrawable drawable = (BitmapDrawable) context.getResources().getDrawable(id); if (drawable != null) { return drawable.getBitmap(); } } return null; } /** * 读取Property文件 */ public static HashMapsimpleProperty2HashMap(Context context, String path) { try { InputStream is = getStream(context, path); return simpleProperty2HashMap(is); } catch (IOException e) { e.printStackTrace(); } return new HashMap (); } private static HashMap simpleProperty2HashMap(InputStream in) throws IOException { HashMap hashMap = new HashMap (); Properties properties = new Properties(); properties.load(in); in.close(); Set keyValue = properties.keySet(); for (Iterator it = keyValue.iterator(); it.hasNext(); ) { String key = (String) it.next(); hashMap.put(key, (String) properties.get(key)); } return hashMap; } /** * 将raw文件拷贝到指定目录 */ public static void copyRawFile(Context ctx, String rawFileName, String to) { String[] names = rawFileName.split("\\."); String toFile = to + "/" + names[0] + "." + names[1]; File file = new File(toFile); if (file.exists()) { return; } try { InputStream is = getStream(ctx, "raw://" + names[0]); OutputStream os = new FileOutputStream(toFile); int byteCount = 0; byte[] bytes = new byte[1024]; while ((byteCount = is.read(bytes)) != -1) { os.write(bytes, 0, byteCount); } os.close(); is.close(); } catch (Exception e) { e.printStackTrace(); } } /** * 基本文件操作 */ public static String FILE_READING_ENCODING = "UTF-8"; public static String FILE_WRITING_ENCODING = "UTF-8"; public static String readFile(String _sFileName, String _sEncoding) throws Exception { StringBuffer buffContent = null; String sLine; FileInputStream fis = null; BufferedReader buffReader = null; if (_sEncoding == null || "".equals(_sEncoding)) { _sEncoding = FILE_READING_ENCODING; } try { fis = new FileInputStream(_sFileName); buffReader = new BufferedReader(new InputStreamReader(fis, _sEncoding)); boolean zFirstLine = "UTF-8".equalsIgnoreCase(_sEncoding); while ((sLine = buffReader.readLine()) != null) { if (buffContent == null) { buffContent = new StringBuffer(); } else { buffContent.append("\n"); } if (zFirstLine) { sLine = removeBomHeaderIfExists(sLine); zFirstLine = false; } buffContent.append(sLine); }// end while return (buffContent == null ? "" : buffContent.toString()); } catch (FileNotFoundException ex) { throw new Exception("要读取的文件没有找到!", ex); } catch (IOException ex) { throw new Exception("读取文件时错误!", ex); } finally { // 增加异常时资源的释放 try { if (buffReader != null) buffReader.close(); if (fis != null) fis.close(); } catch (Exception ex) { ex.printStackTrace(); } } } public static File writeFile(InputStream is, String path, boolean isOverride) throws Exception { String sPath = extractFilePath(path); if (!pathExists(sPath)) { makeDir(sPath, true); } if (!isOverride && fileExists(path)) { if(path.contains(".")) { String suffix = path.substring(path.lastIndexOf(".")); String pre = path.substring(0, path.lastIndexOf(".")); path = pre + "_" + TimeUtils.getNowTime() + suffix; } else { path = path + "_" + TimeUtils.getNowTime(); } } FileOutputStream os = null; File file = null; try { file = new File(path); os = new FileOutputStream(file); int byteCount = 0; byte[] bytes = new byte[1024]; while ((byteCount = is.read(bytes)) != -1) { os.write(bytes, 0, byteCount); } os.flush(); return file; } catch (Exception e) { e.printStackTrace(); throw new Exception("写文件错误", e); } finally { try { if (os != null) os.close(); if (is != null) is.close(); } catch (Exception e) { e.printStackTrace(); } } } public static File writeFile(String path, String content, String encoding, boolean isOverride) throws Exception { if (TextUtils.isEmpty(encoding)) { encoding = FILE_WRITING_ENCODING; } InputStream is = new ByteArrayInputStream(content.getBytes(encoding)); return writeFile(is, path, isOverride); } /** * 从文件的完整路径名(路径+文件名)中提取 路径(包括:Drive+Directroy ) * * @param _sFilePathName * @return */ public static String extractFilePath(String _sFilePathName) { int nPos = _sFilePathName.lastIndexOf('/'); if (nPos < 0) { nPos = _sFilePathName.lastIndexOf('\\'); } return (nPos >= 0 ? _sFilePathName.substring(0, nPos + 1) : ""); } /** * 从文件的完整路径名(路径+文件名)中提取文件名(包含扩展名)
* 如:d:\path\file.ext --> file.ext * * @param _sFilePathName * @return */ public static String extractFileName(String _sFilePathName) { return extractFileName(_sFilePathName, File.separator); } /** * 从文件的完整路径名(路径+文件名)中提取文件名(包含扩展名)
* 如:d:\path\file.ext --> file.ext * * @param _sFilePathName 全文件路径名 * @param _sFileSeparator 文件分隔符 * @return */ public static String extractFileName(String _sFilePathName, String _sFileSeparator) { int nPos = -1; if (_sFileSeparator == null) { nPos = _sFilePathName.lastIndexOf(File.separatorChar); if (nPos < 0) { nPos = _sFilePathName .lastIndexOf(File.separatorChar == '/' ? '\\' : '/'); } } else { nPos = _sFilePathName.lastIndexOf(_sFileSeparator); } if (nPos < 0) { return _sFilePathName; } return _sFilePathName.substring(nPos + 1); } /** * 检查指定文件的路径是否存在 * * @param _sPathFileName 文件名称(含路径) * @return 若存在,则返回true;否则,返回false */ public static boolean pathExists(String _sPathFileName) { String sPath = extractFilePath(_sPathFileName); return fileExists(sPath); } public static boolean fileExists(String _sPathFileName) { File file = new File(_sPathFileName); return file.exists(); } /** * 创建目录 * * @param _sDir 目录名称 * @param _bCreateParentDir 如果父目录不存在,是否创建父目录 * @return */ public static boolean makeDir(String _sDir, boolean _bCreateParentDir) { boolean zResult = false; File file = new File(_sDir); if (_bCreateParentDir) zResult = file.mkdirs(); // 如果父目录不存在,则创建所有必需的父目录 else zResult = file.mkdir(); // 如果父目录不存在,不做处理 if (!zResult) zResult = file.exists(); return zResult; } /** * 移除字符串中的BOM前缀 * * @param _sLine 需要处理的字符串 * @return 移除BOM后的字符串. */ private static String removeBomHeaderIfExists(String _sLine) { if (_sLine == null) { return null; } String line = _sLine; if (line.length() > 0) { char ch = line.charAt(0); // 使用while是因为用一些工具看到过某些文件前几个字节都是0xfffe. // 0xfeff,0xfffe是字节序的不同处理.JVM中,一般是0xfeff while ((ch == 0xfeff || ch == 0xfffe)) { line = line.substring(1); if (line.length() == 0) { break; } ch = line.charAt(0); } } return line; } }
2 网上的工具类
这个工具类也大同小异。其中也有很多和我上面重复的一些方法,也有上面没有的方法。转自Trinea的android-common项目。这里直接贴出来,不做任何更改。希望能对看到的人有帮助。也做一个笔记。
package com.nsu.edu.library.utils; import android.text.TextUtils; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileWriter; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.util.ArrayList; import java.util.List; /** * File Utils *
}
* @return if file not exist, return null, else return content of file
* @throws RuntimeException if an error occurs while operator BufferedReader
*/
public static StringBuilder readFile(String filePath, String charsetName) {
File file = new File(filePath);
StringBuilder fileContent = new StringBuilder("");
if (file == null || !file.isFile()) {
return null;
}
BufferedReader reader = null;
try {
InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
reader = new BufferedReader(is);
String line = null;
while ((line = reader.readLine()) != null) {
if (!fileContent.toString().equals("")) {
fileContent.append("\r\n");
}
fileContent.append(line);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* write file
*
* @param filePath
* @param content
* @param append is append, if true, write to the end of file, else clear content of file and write into it
* @return return false if content is empty, true otherwise
* @throws RuntimeException if an error occurs while operator FileWriter
*/
public static boolean writeFile(String filePath, String content, boolean append) {
if (StringUtils.isEmpty(content)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
fileWriter.write(content);
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* write file
*
* @param filePath
* @param contentList
* @param append is append, if true, write to the end of file, else clear content of file and write into it
* @return return false if contentList is empty, true otherwise
* @throws RuntimeException if an error occurs while operator FileWriter
*/
public static boolean writeFile(String filePath, List contentList, boolean append) {
if (ListUtils.isEmpty(contentList)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
int i = 0;
for (String line : contentList) {
if (i++ > 0) {
fileWriter.write("\r\n");
}
fileWriter.write(line);
}
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* write file, the string will be written to the begin of the file
*
* @param filePath
* @param content
* @return
*/
public static boolean writeFile(String filePath, String content) {
return writeFile(filePath, content, false);
}
/**
* write file, the string list will be written to the begin of the file
*
* @param filePath
* @param contentList
* @return
*/
public static boolean writeFile(String filePath, List contentList) {
return writeFile(filePath, contentList, false);
}
/**
* write file, the bytes will be written to the begin of the file
*
* @param filePath
* @param stream
* @return
* @see {@link #writeFile(String, InputStream, boolean)}
*/
public static boolean writeFile(String filePath, InputStream stream) {
return writeFile(filePath, stream, false);
}
/**
* write file
*
* @param file the file to be opened for writing.
* @param stream the input stream
* @param append if true
, then bytes will be written to the end of the file rather than the beginning
* @return return true
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean writeFile(String filePath, InputStream stream, boolean append) {
return writeFile(filePath != null ? new File(filePath) : null, stream, append);
}
/**
* write file, the bytes will be written to the begin of the file
*
* @param file
* @param stream
* @return
* @see {@link #writeFile(File, InputStream, boolean)}
*/
public static boolean writeFile(File file, InputStream stream) {
return writeFile(file, stream, false);
}
/**
* write file
*
* @param file the file to be opened for writing.
* @param stream the input stream
* @param append if true
, then bytes will be written to the end of the file rather than the beginning
* @return return true
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean writeFile(File file, InputStream stream, boolean append) {
OutputStream o = null;
try {
makeDirs(file.getAbsolutePath());
o = new FileOutputStream(file, append);
byte data[] = new byte[1024];
int length = -1;
while ((length = stream.read(data)) != -1) {
o.write(data, 0, length);
}
o.flush();
return true;
} catch (FileNotFoundException e) {
throw new RuntimeException("FileNotFoundException occurred. ", e);
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(o);
IOUtils.close(stream);
}
}
/**
* move file
*
* @param sourceFilePath
* @param destFilePath
*/
public static void moveFile(String sourceFilePath, String destFilePath) {
if (TextUtils.isEmpty(sourceFilePath) || TextUtils.isEmpty(destFilePath)) {
throw new RuntimeException("Both sourceFilePath and destFilePath cannot be null.");
}
moveFile(new File(sourceFilePath), new File(destFilePath));
}
/**
* move file
*
* @param srcFile
* @param destFile
*/
public static void moveFile(File srcFile, File destFile) {
boolean rename = srcFile.renameTo(destFile);
if (!rename) {
copyFile(srcFile.getAbsolutePath(), destFile.getAbsolutePath());
deleteFile(srcFile.getAbsolutePath());
}
}
/**
* copy file
*
* @param sourceFilePath
* @param destFilePath
* @return
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean copyFile(String sourceFilePath, String destFilePath) {
InputStream inputStream = null;
try {
inputStream = new FileInputStream(sourceFilePath);
} catch (FileNotFoundException e) {
throw new RuntimeException("FileNotFoundException occurred. ", e);
}
return writeFile(destFilePath, inputStream);
}
/**
* read file to string list, a element of list is a line
*
* @param filePath
* @param charsetName The name of a supported {@link java.nio.charset.Charset
charset}
* @return if file not exist, return null, else return content of file
* @throws RuntimeException if an error occurs while operator BufferedReader
*/
public static List readFileToList(String filePath, String charsetName) {
File file = new File(filePath);
List fileContent = new ArrayList();
if (file == null || !file.isFile()) {
return null;
}
BufferedReader reader = null;
try {
InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
reader = new BufferedReader(is);
String line = null;
while ((line = reader.readLine()) != null) {
fileContent.add(line);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* get file name from path, not include suffix
*
*
* getFileNameWithoutExtension(null) = null
* getFileNameWithoutExtension("") = ""
* getFileNameWithoutExtension(" ") = " "
* getFileNameWithoutExtension("abc") = "abc"
* getFileNameWithoutExtension("a.mp3") = "a"
* getFileNameWithoutExtension("a.b.rmvb") = "a.b"
* getFileNameWithoutExtension("c:\\") = ""
* getFileNameWithoutExtension("c:\\a") = "a"
* getFileNameWithoutExtension("c:\\a.b") = "a"
* getFileNameWithoutExtension("c:a.txt\\a") = "a"
* getFileNameWithoutExtension("/home/admin") = "admin"
* getFileNameWithoutExtension("/home/admin/a.txt/b.mp3") = "b"
*
*
* @param filePath
* @return file name from path, not include suffix
* @see
*/
public static String getFileNameWithoutExtension(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (filePosi == -1) {
return (extenPosi == -1 ? filePath : filePath.substring(0, extenPosi));
}
if (extenPosi == -1) {
return filePath.substring(filePosi + 1);
}
return (filePosi < extenPosi ? filePath.substring(filePosi + 1, extenPosi) : filePath.substring(filePosi + 1));
}
/**
* get file name from path, include suffix
*
*
* getFileName(null) = null
* getFileName("") = ""
* getFileName(" ") = " "
* getFileName("a.mp3") = "a.mp3"
* getFileName("a.b.rmvb") = "a.b.rmvb"
* getFileName("abc") = "abc"
* getFileName("c:\\") = ""
* getFileName("c:\\a") = "a"
* getFileName("c:\\a.b") = "a.b"
* getFileName("c:a.txt\\a") = "a"
* getFileName("/home/admin") = "admin"
* getFileName("/home/admin/a.txt/b.mp3") = "b.mp3"
*
*
* @param filePath
* @return file name from path, include suffix
*/
public static String getFileName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -1) ? filePath : filePath.substring(filePosi + 1);
}
/**
* get folder name from path
*
*
* getFolderName(null) = null
* getFolderName("") = ""
* getFolderName(" ") = ""
* getFolderName("a.mp3") = ""
* getFolderName("a.b.rmvb") = ""
* getFolderName("abc") = ""
* getFolderName("c:\\") = "c:"
* getFolderName("c:\\a") = "c:"
* getFolderName("c:\\a.b") = "c:"
* getFolderName("c:a.txt\\a") = "c:a.txt"
* getFolderName("c:a\\b\\c\\d.txt") = "c:a\\b\\c"
* getFolderName("/home/admin") = "/home"
* getFolderName("/home/admin/a.txt/b.mp3") = "/home/admin/a.txt"
*
*
* @param filePath
* @return
*/
public static String getFolderName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -1) ? "" : filePath.substring(0, filePosi);
}
/**
* get suffix of file from path
*
*
* getFileExtension(null) = ""
* getFileExtension("") = ""
* getFileExtension(" ") = " "
* getFileExtension("a.mp3") = "mp3"
* getFileExtension("a.b.rmvb") = "rmvb"
* getFileExtension("abc") = ""
* getFileExtension("c:\\") = ""
* getFileExtension("c:\\a") = ""
* getFileExtension("c:\\a.b") = "b"
* getFileExtension("c:a.txt\\a") = ""
* getFileExtension("/home/admin") = ""
* getFileExtension("/home/admin/a.txt/b") = ""
* getFileExtension("/home/admin/a.txt/b.mp3") = "mp3"
*
*
* @param filePath
* @return
*/
public static String getFileExtension(String filePath) {
if (StringUtils.isBlank(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (extenPosi == -1) {
return "";
}
return (filePosi >= extenPosi) ? "" : filePath.substring(extenPosi + 1);
}
/**
* Creates the directory named by the trailing filename of this file, including the complete directory path required
* to create this directory.
*
*
* Attentions:
* - makeDirs("C:\\Users\\Trinea") can only create users folder
* - makeFolder("C:\\Users\\Trinea\\") can create Trinea folder
*
*
* @param filePath
* @return true if the necessary directories have been created or the target directory already exists, false one of
* the directories can not be created.
*
* - if {@link FileUtils#getFolderName(String)} return null, return false
* - if target directory already exists, return true
* - return {@link File#makeFolder}
*
*/
public static boolean makeDirs(String filePath) {
String folderName = getFolderName(filePath);
if (StringUtils.isEmpty(folderName)) {
return false;
}
File folder = new File(folderName);
return (folder.exists() && folder.isDirectory()) ? true : folder.mkdirs();
}
/**
* @param filePath
* @return
* @see #makeDirs(String)
*/
public static boolean makeFolders(String filePath) {
return makeDirs(filePath);
}
/**
* Indicates if this file represents a file on the underlying file system.
*
* @param filePath
* @return
*/
public static boolean isFileExist(String filePath) {
if (StringUtils.isBlank(filePath)) {
return false;
}
File file = new File(filePath);
return (file.exists() && file.isFile());
}
/**
* Indicates if this file represents a directory on the underlying file system.
*
* @param directoryPath
* @return
*/
public static boolean isFolderExist(String directoryPath) {
if (StringUtils.isBlank(directoryPath)) {
return false;
}
File dire = new File(directoryPath);
return (dire.exists() && dire.isDirectory());
}
/**
* delete file or directory
*
* - if path is null or empty, return true
* - if path not exist, return true
* - if path exist, delete recursion. return true
*
*
* @param path
* @return
*/
public static boolean deleteFile(String path) {
if (StringUtils.isBlank(path)) {
return true;
}
File file = new File(path);
if (!file.exists()) {
return true;
}
if (file.isFile()) {
return file.delete();
}
if (!file.isDirectory()) {
return false;
}
for (File f : file.listFiles()) {
if (f.isFile()) {
f.delete();
} else if (f.isDirectory()) {
deleteFile(f.getAbsolutePath());
}
}
return file.delete();
}
/**
* get file size
*
* - if path is null or empty, return -1
* - if path exist and it is a file, return file size, else return -1
*
*
* @param path
* @return returns the length of this file in bytes. returns -1 if the file does not exist.
*/
public static long getFileSize(String path) {
if (StringUtils.isBlank(path)) {
return -1;
}
File file = new File(path);
return (file.exists() && file.isFile() ? file.length() : -1);
}
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