java 获取目录下所有文件及文件目录
java获取文件或文件夹内最后修改时间：
/**
* @param file
* File
* @return long
*/
public static long getFolderLastModifyTime(File file) {
long result = 0;
if (file == null || !file.exists()) {
Utils.logd(TAG, "Given file not exist.");
return result;
}
if (file.isFile()) {
result = file.lastModified();
} else {
File[] fileList = file.listFiles();
if (fileList == null || fileList.length == 0) {
Utils.loge(TAG, "No sub files in folder:" + file.getAbsolutePath());
return result;
}
for (File subFile : fileList) {
long lastModifiedTime = 0;
if (subFile.isFile()) {
lastModifiedTime = subFile.lastModified();
} else {
lastModifiedTime = getFolderLastModifyTime(subFile);
}
if (lastModifiedTime > result) {
result = lastModifiedTime;
}
}
}
return result;
}java复制文件或文件 夹
/**
* @param sourceFilePath
* String
* @param targetFilePath
* String
* @return boolean
*/
public static boolean doCopy(String sourceFilePath, String targetFilePath) {
Utils.logi(TAG, "-->doCopy() from " + sourceFilePath + " to " + targetFilePath);
File sourceFile = new File(sourceFilePath);
if (null == sourceFile || !sourceFile.exists()) {
Utils.logw(TAG,
"The sourceFilePath = " + sourceFilePath + " is not existes, do copy failed!");
return false;
}
// Get all files and sub directories under the current directory
File[] files = sourceFile.listFiles();
if (null == files) {
// Current file is not a directory
String tagLogPath = sourceFile.getAbsolutePath();
return copyFile(tagLogPath, targetFilePath);
} else {
// Current file is a directory
File targetFile = new File(targetFilePath);
if (!targetFile.exists()) {
targetFile.mkdirs();
}
for (File subFile : files) {
doCopy(subFile.getAbsolutePath(),
targetFilePath + File.separator + subFile.getName());
}
}
return true;
}
private static final int COPY_BUFFER_SIZE = 1024;
private static boolean copyFile(String sourceFilePath, String targetFilePath) {
Utils.logi(TAG, "-->copyFile() from " + sourceFilePath + " to " + targetFilePath);
File sourceFile = new File(sourceFilePath);
if (!sourceFile.exists()) {
Utils.logw(TAG, "The sourceFilePath = " + sourceFilePath + " is not existes, do copy failed!");
return false;
}
File targetFile = new File(targetFilePath);
if (targetFile.exists()) {
targetFile.delete();
}
FileInputStream fis = null;
FileOutputStream fos = null;
try {
fis = new FileInputStream(sourceFile);
File parentFile = targetFile.getParentFile();
if (!parentFile.exists()) {
parentFile.mkdirs();
}
LogFileManager.createNewFile(targetFile);
fos = LogFileManager.getFileOutputStream(targetFile);
if (fos == null) {
return false;
}
byte[] temp = new byte[COPY_BUFFER_SIZE];
int len;
while ((len = fis.read(temp)) != -1) {
fos.write(temp, 0, len);
}
fos.flush();
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
try {
if (fos != null) {
fos.close();
}
if (fis != null) {
fis.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return true;
}java获取文件或文件夹的大小
/**
* Get file or folder size of input filePath.
*
* @param filePath the path of file
* @return filePath size
*/
public static long getFileSize(String filePath) {
long size = 0;
if (filePath == null) {
return 0;
}
File fileRoot = new File(filePath);
if (fileRoot == null || !fileRoot.exists()) {
return 0;
}
if (!fileRoot.isDirectory()) {
size = fileRoot.length();
} else {
File[] files = fileRoot.listFiles();
// why get a null here ?? maybe caused by permission denied
if (files == null || files.length == 0) {
Utils.logv(TAG, "Loop folder [" + filePath + "] get a null/empty list");
return 0;
}
for (File file : files) {
if (file == null) {
continue;
}
size += getFileSize(file.getAbsolutePath());
}
}
return size;
}
java判断文件是否存在及是否有内容
public static boolean isFileExistOrNotEmpty(String filePath) {
try {
File f = new File(filePath);
if (!f.exists() || f.length() == 0) {
return false;
}
} catch (Exception e) {
return false;
}
return true;
}
java 获取目录下所有文件及文件目录,
public static List<File> getAllFiles(File sourceFile, boolean containFolder) {
Stack<File> dirStack = new Stack<File>();
List<File> allFile = new LinkedList<File>();
if(!sourceFile.exists()) {
Log.e(TAG, "file: " + sourceFile + " does not exist");
return allFile;
}
if (sourceFile.isDirectory()) {
dirStack.add(sourceFile);
} else {
allFile.add(sourceFile);
}
while(!dirStack.empty()) {
File file = dirStack.pop();
if(containFolder) {
allFile.add(file);
}
if (file != null) {
File fileArray[] = file.listFiles();
if(fileArray != null){
for(File f : fileArray ) {
if(f.isDirectory()) {
dirStack.push(f);
} else {
allFile.add(f);
}
}
}
}
}
return allFile;
}java压缩文件或文件夹
/**
* @param sourceFilePath String
* @param targetFilePath String
* @return boolean
*/
public static boolean doZip(String sourceFilePath, String targetFilePath) {
Utils.logi(TAG, "-->doZip from " + sourceFilePath + " to " + targetFilePath);
File sourceFile = new File(sourceFilePath);
if (!sourceFile.exists()) {
Utils.logw(TAG,
"The sourceFilePath = " + sourceFilePath + " is not existes, do zip failed!");
return false;
}
File targetFile = new File(targetFilePath);
if (targetFile.exists()) {
LogFileManager.delete(targetFile);
}
ZipOutputStream outZip = null;
FileOutputStream fileOutputStream = null;
try {
fileOutputStream =
LogFileManager.getFileOutputStream(new File(targetFilePath));
if (fileOutputStream == null) {
return false;
}
outZip = new ZipOutputStream(fileOutputStream);
zipFile(sourceFilePath, "", outZip);
outZip.flush();
outZip.finish();
fileOutputStream.close();
outZip.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
try {
if (fileOutputStream != null) {
fileOutputStream.close();
}
if (outZip != null) {
outZip.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return true;
}
private static final int ZIP_BUFFER_SIZE = 100 * 1024;
private static boolean zipFile(String srcRootPath, String fileRelativePath,
ZipOutputStream zout) {
Utils.logd(TAG, "zipFile(), srcRootPath=" + srcRootPath
+ ", fileRelativePath = " + fileRelativePath);
boolean result = false;
File file = new File(srcRootPath);
if (fileRelativePath == null || fileRelativePath.isEmpty()) {
fileRelativePath = file.getName();
}
if (file.exists()) {
if (file.isFile()) {
FileInputStream in = null;
try {
in = new FileInputStream(file);
ZipEntry entry = new ZipEntry(fileRelativePath);
zout.putNextEntry(entry);
int len = 0;
byte[] buffer = new byte[ZIP_BUFFER_SIZE];
while ((len = in.read(buffer)) > -1) {
zout.write(buffer, 0, len);
}
zout.closeEntry();
zout.flush();
result = true;
} catch (FileNotFoundException e) {
Utils.loge(TAG, "FileNotFoundException", e);
} catch (IOException e) {
Utils.loge(TAG, "IOException", e);
} finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return result;
} else {
result = true;
String[] fileList = file.list();
if (fileList == null) {
return false;
}
if (fileList.length <= 0) {
ZipEntry entry = new ZipEntry(fileRelativePath + File.separator);
try {
zout.putNextEntry(entry);
zout.closeEntry();
} catch (IOException e) {
e.printStackTrace();
return false;
}
}
for (String subFileName : fileList) {
String newRelativePath = fileRelativePath.isEmpty() ? subFileName
: (fileRelativePath + File.separator + subFileName);
if (!zipFile(srcRootPath + File.separator + subFileName,
newRelativePath, zout)) {
result = false;
Utils.loge(TAG, "File [" + subFileName + "] zip failed");
}
}
return result;
}
} else {
Utils.loge(TAG, "File [" + file.getPath() + "] does not exitst");
return false;
}
}java 删除文件夹及文件夹所有文件与目录
public static boolean deleteContentsAndDir(File dir) {
if (deleteContents(dir)) {
return dir.delete();
} else {
return false;
}
}
public static boolean deleteContents(File dir) {
File[] files = dir.listFiles();
boolean success = true;
if (files != null) {
for (File file : files) {
if (file.isDirectory()) {
success &= deleteContents(file);
}
if (!file.delete()) {
Log.i("androidodm", "Failed to delete " + file);
success = false;
}
}
}
return success;
}java 删除某个时间前的文件 可以删除指定文件数量
public static boolean deleteOlderFiles(File dir, int minCount, long minAgeMs) {
if (minCount < 0 || minAgeMs < 0) {
throw new IllegalArgumentException("Constraints must be positive or 0");
}
final File[] files = dir.listFiles();
if (files == null) return false;
// Sort with newest files first
Arrays.sort(files, new Comparator<File>() {
@Override
public int compare(File lhs, File rhs) {
return Long.compare(rhs.lastModified(), lhs.lastModified());
}
});
// Keep at least minCount files
boolean deleted = false;
for (int i = minCount; i < files.length; i++) {
final File file = files[i];
// Keep files newer than minAgeMs
final long age = System.currentTimeMillis() - file.lastModified();
if (age > minAgeMs) {
if (file.delete()) {
Log.d(TAG, "Deleted old file " + file);
deleted = true;
}
}
}
return deleted;
}java 删除文件目录
public static void deleteAll(File target) {
if (target.isDirectory()) {
for (File child : target.listFiles()) {
deleteAll(child);
}
}
target.delete();
}java 读取文件的最后一行内容
public static String getLastLine(String filePath){
String res = "";
File file = new File(filePath);
if(!file.exists()){
return res;
}
RandomAccessFile raf = null;
try {
raf = new RandomAccessFile(file,"r");
long len = raf.length();
if(len == 0L){
return res;
}
long pos = len -1;
while(pos > 0){
pos --;
raf.seek(pos);
if(raf.readByte() == '\n'){
break;
}
}
if(pos == 0){
raf.seek(0);
}
byte[] bytes = new byte[(int)(len - pos)];
raf.read(bytes);
res = new String(bytes);
} catch (IOException e) {
e.printStackTrace();
}finally {
try {
if(raf != null){
raf.close();
raf = null;
}
} catch (IOException e) {
e.printStackTrace();
}
}
return res;
}java 保存文件
public static boolean writeFile(String filePath, String content) {
boolean res = true;
File file = new File(filePath);
File dir = new File(file.getParent());
if (!dir.exists())
dir.mkdirs();
try {
if (!file.exists()) {
file.createNewFile();
} else {
file.delete();
file.createNewFile();
}
FileWriter mFileWriter = new FileWriter(file, false);
mFileWriter.write(content);
mFileWriter.close();
} catch (IOException e) {
res = false;
}
return res;
}java 读文件
private int readNodeValue(String file,int defaultValue){
int vales = defaultValue;
try{
BufferedReader bufferedread = new BufferedReader(new FileReader(filepath));
value = Interger.parseInt(bufferedread.readLine(),10)
bufferedread.close();
}catch(Exception e){
e.getMessage();
}
return value;
}java 保存文件
public static long readFileToSaveNewFile(FileInputStream fis, String destFilePath) throws Exception {
if (fis == null || destFilePath == null)
return -1;
long totalLen = 0;
BufferedInputStream bin = null;
BufferedOutputStream bout = null;
File destFile = new File(destFilePath);
if (!destFile.exists()) {
destFile.createNewFile();
}
FileOutputStream fos = new FileOutputStream(destFile);
try {
try {
bin = new BufferedInputStream(fis, 1024);
bout = new BufferedOutputStream(fos, 1024);
byte[] buffer = new byte[1024];
int len = 0;
while ((len = bin.read(buffer)) > 0) {
bout.write(buffer, 0, len);
totalLen += len;
}
} finally {
if (null != bin) {
bin.close();
}
if (null != bout) {
bout.close();
}
if(null != fos) {
fos.close();
}
}
} catch (Exception e) {
e.printStackTrace();
}
return totalLen;
}JAVA File对文件内容的操作：
java IO文件操作
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