/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// BEGIN android-note
// We've dropped Windows support, except where it's exposed: we still support
// non-Unix separators in serialized File objects, for example, but we don't
// have any code for UNC paths or case-insensitivity.
// We've also changed the JNI interface to better match what the Java actually wants.
// (The JNI implementation is also much simpler.)
// Some methods have been rewritten to reduce unnecessary allocation.
// Some duplication has been factored out.
// END android-note
package java.io;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.security.AccessController;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.List;
import org.apache.harmony.luni.util.DeleteOnExit;
import org.apache.harmony.luni.util.Msg;
import org.apache.harmony.luni.util.PriviAction;
import org.apache.harmony.luni.util.Util;
/**
* An "abstract" representation of a file system entity identified by a
* pathname. The pathname may be absolute (relative to the root directory
* of the file system) or relative to the current directory in which the program
* is running.
* <p>
* The actual file referenced by a {@code File} may or may not exist. It may
* also, despite the name {@code File}, be a directory or other non-regular
* file.
* <p>
* This class provides limited functionality for getting/setting file
* permissions, file type, and last modified time.
* <p>
* Although Java doesn't specify a character encoding for filenames, on Android
* Java strings are converted to UTF-8 byte sequences when sending filenames to
* the operating system, and byte sequences returned by the operating system
* (from the various {@code list} methods) are converted to Java strings by
* decoding them as UTF-8 byte sequences.
*
* @see java.io.Serializable
* @see java.lang.Comparable
*/
public class File implements Serializable, Comparable<File> {
private static final long serialVersionUID = 301077366599181567L;
private static final String EMPTY_STRING = ""; //$NON-NLS-1$
// Caches the UTF-8 Charset for newCString.
private static final Charset UTF8 = Charset.forName("UTF-8");
/**
* The system dependent file separator character.
* This field is initialized from the system property "file.separator".
* Later changes to that property will have no effect on this field or this class.
*/
public static final char separatorChar;
/**
* The system dependent file separator string.
* This field is a single-character string equal to String.valueOf(separatorChar).
*/
public static final String separator;
/**
* The system dependent path separator character.
* This field is initialized from the system property "path.separator".
* Later changes to that property will have no effect on this field or this class.
*/
public static final char pathSeparatorChar;
/**
* The system dependent path separator string.
* This field is a single-character string equal to String.valueOf(pathSeparatorChar).
*/
public static final String pathSeparator;
/* Temp file counter */
private static int counter;
/**
* The path we return from getPath. This is almost the path we were
* given, but without duplicate adjacent slashes and without trailing
* slashes (except for the special case of the root directory). This
* path may be the empty string.
*/
private String path;
/**
* The cached UTF-8 byte sequence corresponding to 'path'.
* This is suitable for direct use by our JNI, and includes a trailing NUL.
* For non-absolute paths, the "user.dir" property is prepended: that is,
* this byte sequence usually represents an absolute path (the exception
* being if the user overwrites the "user.dir" property with a non-absolute
* path).
*/
transient byte[] pathBytes;
static {
// The default protection domain grants access to these properties.
separatorChar = System.getProperty("file.separator", "/").charAt(0); //$NON-NLS-1$ //$NON-NLS-2$
pathSeparatorChar = System.getProperty("path.separator", ":").charAt(0); //$NON-NLS-1$//$NON-NLS-2$
separator = String.valueOf(separatorChar);
pathSeparator = String.valueOf(pathSeparatorChar);
}
/**
* Constructs a new file using the specified directory and name.
*
* @param dir
* the directory where the file is stored.
* @param name
* the file's name.
* @throws NullPointerException
* if {@code name} is {@code null}.
*/
public File(File dir, String name) {
this(dir == null ? null : dir.getPath(), name);
}
/**
* Constructs a new file using the specified path.
*
* @param path
* the path to be used for the file.
*/
public File(String path) {
init(path);
}
/**
* Constructs a new File using the specified directory path and file name,
* placing a path separator between the two.
*
* @param dirPath
* the path to the directory where the file is stored.
* @param name
* the file's name.
* @throws NullPointerException
* if {@code name} is {@code null}.
*/
public File(String dirPath, String name) {
if (name == null) {
throw new NullPointerException();
}
if (dirPath == null || dirPath.length() == 0) {
init(name);
} else if (name.length() == 0) {
init(dirPath);
} else {
init(join(dirPath, name));
}
}
/**
* Constructs a new File using the path of the specified URI. {@code uri}
* needs to be an absolute and hierarchical Unified Resource Identifier with
* file scheme and non-empty path component, but with undefined authority,
* query or fragment components.
*
* @param uri
* the Unified Resource Identifier that is used to construct this
* file.
* @throws IllegalArgumentException
* if {@code uri} does not comply with the conditions above.
* @see #toURI
* @see java.net.URI
*/
public File(URI uri) {
// check pre-conditions
checkURI(uri);
init(uri.getPath());
}
private void init(String dirtyPath) {
// Keep a copy of the cleaned-up string path.
this.path = fixSlashes(dirtyPath);
// Cache the UTF-8 bytes we need for the JNI.
// TODO: we shouldn't do this caching at all; the RI demonstrably doesn't.
if (path.length() > 0 && path.charAt(0) == separatorChar) { // http://b/2486943
this.pathBytes = newCString(path);
return;
}
String userDir = AccessController.doPrivileged(
new PriviAction<String>("user.dir")); //$NON-NLS-1$
this.pathBytes = newCString(path.length() == 0 ? userDir : join(userDir, path));
}
private byte[] newCString(String s) {
ByteBuffer buffer = UTF8.encode(s);
// Add a trailing NUL, because this byte[] is going to be used as a char*.
int byteCount = buffer.limit() + 1;
byte[] bytes = new byte[byteCount];
buffer.get(bytes, 0, byteCount - 1);
// This is an awful mistake, because '\' is a perfectly acceptable
// character on Linux/Android. But we've shipped so many versions
// that behaved like this, I'm too scared to change it.
for (int i = 0; i < bytes.length; ++i) {
if (bytes[i] == '\\') {
bytes[i] = '/';
}
}
return bytes;
}
// Removes duplicate adjacent slashes and any trailing slash.
private String fixSlashes(String origPath) {
// Remove duplicate adjacent slashes.
boolean lastWasSlash = false;
char[] newPath = origPath.toCharArray();
int length = newPath.length;
int newLength = 0;
for (int i = 0; i < length; ++i) {
char ch = newPath[i];
if (ch == '/') {
if (!lastWasSlash) {
newPath[newLength++] = separatorChar;
lastWasSlash = true;
}
} else {
newPath[newLength++] = ch;
lastWasSlash = false;
}
}
// Remove any trailing slash (unless this is the root of the file system).
if (lastWasSlash && newLength > 1) {
newLength--;
}
// Reuse the original string if possible.
return (newLength != length) ? new String(newPath, 0, newLength) : origPath;
}
// Joins two path components, adding a separator only if necessary.
private String join(String prefix, String suffix) {
int prefixLength = prefix.length();
boolean haveSlash = (prefixLength > 0 && prefix.charAt(prefixLength - 1) == separatorChar);
if (!haveSlash) {
haveSlash = (suffix.length() > 0 && suffix.charAt(0) == separatorChar);
}
return haveSlash ? (prefix + suffix) : (prefix + separatorChar + suffix);
}
@SuppressWarnings("nls")
private void checkURI(URI uri) {
if (!uri.isAbsolute()) {
throw new IllegalArgumentException(Msg.getString("K031a", uri));
} else if (!uri.getRawSchemeSpecificPart().startsWith("/")) {
throw new IllegalArgumentException(Msg.getString("K031b", uri));
}
String temp = uri.getScheme();
if (temp == null || !temp.equals("file")) {
throw new IllegalArgumentException(Msg.getString("K031c", uri));
}
temp = uri.getRawPath();
if (temp == null || temp.length() == 0) {
throw new IllegalArgumentException(Msg.getString("K031d", uri));
}
if (uri.getRawAuthority() != null) {
throw new IllegalArgumentException(Msg.getString("K031e",
new String[] { "authority", uri.toString() }));
}
if (uri.getRawQuery() != null) {
throw new IllegalArgumentException(Msg.getString("K031e",
new String[] { "query", uri.toString() }));
}
if (uri.getRawFragment() != null) {
throw new IllegalArgumentException(Msg.getString("K031e",
new String[] { "fragment", uri.toString() }));
}
}
/**
* Lists the file system roots. The Java platform may support zero or more
* file systems, each with its own platform-dependent root. Further, the
* canonical pathname of any file on the system will always begin with one
* of the returned file system roots.
*
* @return the array of file system roots.
*/
public static File[] listRoots() {
return new File[] { new File("/") };
}
/**
* Indicates whether the current context is allowed to read from this file.
*
* @return {@code true} if this file can be read, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies the
* read request.
*/
public boolean canRead() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return isReadableImpl(pathBytes);
}
private native boolean isReadableImpl(byte[] filePath);
/**
* Indicates whether the current context is allowed to write to this file.
*
* @return {@code true} if this file can be written, {@code false}
* otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies the
* write request.
*/
public boolean canWrite() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
}
return isWritableImpl(pathBytes);
}
private native boolean isWritableImpl(byte[] filePath);
/**
* Returns the relative sort ordering of the paths for this file and the
* file {@code another}. The ordering is platform dependent.
*
* @param another
* a file to compare this file to
* @return an int determined by comparing the two paths. Possible values are
* described in the Comparable interface.
* @see Comparable
*/
public int compareTo(File another) {
return this.getPath().compareTo(another.getPath());
}
/**
* Deletes this file. Directories must be empty before they will be deleted.
*
* @return {@code true} if this file was deleted, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies the
* request.
* @see java.lang.SecurityManager#checkDelete
*/
public boolean delete() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkDelete(path);
}
return deleteImpl(pathBytes);
}
private native boolean deleteImpl(byte[] filePath);
/**
* Schedules this file to be automatically deleted once the virtual machine
* terminates. This will only happen when the virtual machine terminates
* normally as described by the Java Language Specification section 12.9.
*
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies the
* request.
*/
public void deleteOnExit() {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkDelete(path);
}
DeleteOnExit.getInstance().addFile(getAbsoluteName());
}
/**
* Compares {@code obj} to this file and returns {@code true} if they
* represent the <em>same</em> object using a path specific comparison.
*
* @param obj
* the object to compare this file with.
* @return {@code true} if {@code obj} is the same as this object,
* {@code false} otherwise.
*/
@Override
public boolean equals(Object obj) {
if (!(obj instanceof File)) {
return false;
}
return path.equals(((File) obj).getPath());
}
/**
* Returns a boolean indicating whether this file can be found on the
* underlying file system.
*
* @return {@code true} if this file exists, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #getPath
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
*/
public boolean exists() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return existsImpl(pathBytes);
}
private native boolean existsImpl(byte[] filePath);
/**
* Returns the absolute path of this file.
*
* @return the absolute file path.
*/
public String getAbsolutePath() {
return Util.toUTF8String(pathBytes, 0, pathBytes.length - 1);
}
/**
* Returns a new file constructed using the absolute path of this file.
*
* @return a new file from this file's absolute path.
* @see java.lang.SecurityManager#checkPropertyAccess
*/
public File getAbsoluteFile() {
return new File(this.getAbsolutePath());
}
/**
* Returns the absolute path of this file with all references resolved. An
* <em>absolute</em> path is one that begins at the root of the file
* system. The canonical path is one in which all references have been
* resolved. For the cases of '..' and '.', where the file system supports
* parent and working directory respectively, these are removed and replaced
* with a direct directory reference. If the file does not exist,
* getCanonicalPath() may not resolve any references and simply returns an
* absolute path name or throws an IOException.
*
* @return the canonical path of this file.
* @throws IOException
* if an I/O error occurs.
*/
public String getCanonicalPath() throws IOException {
// BEGIN android-removed
// Caching the canonical path is bogus. Users facing specific
// performance problems can perform their own caching, with
// eviction strategies that are appropriate for their application.
// A VM-wide cache with no mechanism to evict stale elements is a
// disservice to applications that need up-to-date data.
// String canonPath = FileCanonPathCache.get(absPath);
// if (canonPath != null) {
// return canonPath;
// }
// END android-removed
byte[] result = pathBytes;
if(separatorChar == '/') {
// resolve the full path first
result = resolveLink(result, result.length, false);
// resolve the parent directories
result = resolve(result);
}
int numSeparators = 1;
for (int i = 0; i < result.length; i++) {
if (result[i] == separatorChar) {
numSeparators++;
}
}
int sepLocations[] = new int[numSeparators];
int rootLoc = 0;
if (separatorChar != '/') {
if (result[0] == '\\') {
rootLoc = (result.length > 1 && result[1] == '\\') ? 1 : 0;
} else {
rootLoc = 2; // skip drive i.e. c:
}
}
byte newResult[] = new byte[result.length + 1];
int newLength = 0, lastSlash = 0, foundDots = 0;
sepLocations[lastSlash] = rootLoc;
for (int i = 0; i <= result.length; i++) {
if (i < rootLoc) {
newResult[newLength++] = result[i];
} else {
if (i == result.length || result[i] == separatorChar) {
if (i == result.length && foundDots == 0) {
break;
}
if (foundDots == 1) {
/* Don't write anything, just reset and continue */
foundDots = 0;
continue;
}
if (foundDots > 1) {
/* Go back N levels */
lastSlash = lastSlash > (foundDots - 1) ? lastSlash
- (foundDots - 1) : 0;
newLength = sepLocations[lastSlash] + 1;
foundDots = 0;
continue;
}
sepLocations[++lastSlash] = newLength;
newResult[newLength++] = (byte) separatorChar;
continue;
}
if (result[i] == '.') {
foundDots++;
continue;
}
/* Found some dots within text, write them out */
if (foundDots > 0) {
for (int j = 0; j < foundDots; j++) {
newResult[newLength++] = (byte) '.';
}
}
newResult[newLength++] = result[i];
foundDots = 0;
}
}
// remove trailing slash
if (newLength > (rootLoc + 1)
&& newResult[newLength - 1] == separatorChar) {
newLength--;
}
newResult[newLength] = 0;
newResult = getCanonImpl(newResult);
newLength = newResult.length;
// BEGIN android-changed
// caching the canonical path is completely bogus
return Util.toUTF8String(newResult, 0, newLength);
// FileCanonPathCache.put(absPath, canonPath);
// return canonPath;
// END android-changed
}
/*
* Resolve symbolic links in the parent directories.
*/
private byte[] resolve(byte[] newResult) throws IOException {
int last = 1, nextSize, linkSize;
byte[] linkPath = newResult, bytes;
boolean done, inPlace;
for (int i = 1; i <= newResult.length; i++) {
if (i == newResult.length || newResult[i] == separatorChar) {
done = i >= newResult.length - 1;
// if there is only one segment, do nothing
if (done && linkPath.length == 1) {
return newResult;
}
inPlace = false;
if (linkPath == newResult) {
bytes = newResult;
// if there are no symbolic links, terminate the C string
// instead of copying
if (!done) {
inPlace = true;
newResult[i] = '\0';
}
} else {
nextSize = i - last + 1;
linkSize = linkPath.length;
if (linkPath[linkSize - 1] == separatorChar) {
linkSize--;
}
bytes = new byte[linkSize + nextSize];
System.arraycopy(linkPath, 0, bytes, 0, linkSize);
System.arraycopy(newResult, last - 1, bytes, linkSize,
nextSize);
// the full path has already been resolved
}
if (done) {
return bytes;
}
linkPath = resolveLink(bytes, inPlace ? i : bytes.length, true);
if (inPlace) {
newResult[i] = '/';
}
last = i + 1;
}
}
throw new InternalError();
}
/*
* Resolve a symbolic link. While the path resolves to an existing path,
* keep resolving. If an absolute link is found, resolve the parent
* directories if resolveAbsolute is true.
*/
private byte[] resolveLink(byte[] pathBytes, int length,
boolean resolveAbsolute) throws IOException {
boolean restart = false;
byte[] linkBytes, temp;
do {
linkBytes = getLinkImpl(pathBytes);
if (linkBytes == pathBytes) {
break;
}
if (linkBytes[0] == separatorChar) {
// link to an absolute path, if resolving absolute paths,
// resolve the parent dirs again
restart = resolveAbsolute;
pathBytes = linkBytes;
} else {
int last = length - 1;
while (pathBytes[last] != separatorChar) {
last--;
}
last++;
temp = new byte[last + linkBytes.length];
System.arraycopy(pathBytes, 0, temp, 0, last);
System.arraycopy(linkBytes, 0, temp, last, linkBytes.length);
pathBytes = temp;
}
length = pathBytes.length;
} while (existsImpl(pathBytes));
// resolve the parent directories
if (restart) {
return resolve(pathBytes);
}
return pathBytes;
}
private native byte[] getLinkImpl(byte[] filePath);
/**
* Returns a new file created using the canonical path of this file.
* Equivalent to {@code new File(this.getCanonicalPath())}.
*
* @return the new file constructed from this file's canonical path.
* @throws IOException
* if an I/O error occurs.
* @see java.lang.SecurityManager#checkPropertyAccess
*/
public File getCanonicalFile() throws IOException {
return new File(getCanonicalPath());
}
private native byte[] getCanonImpl(byte[] filePath);
/**
* Returns the name of the file or directory represented by this file.
*
* @return this file's name or an empty string if there is no name part in
* the file's path.
*/
public String getName() {
int separatorIndex = path.lastIndexOf(separator);
return (separatorIndex < 0) ? path : path.substring(separatorIndex + 1,
path.length());
}
/**
* Returns the pathname of the parent of this file. This is the path up to
* but not including the last name. {@code null} is returned if there is no
* parent.
*
* @return this file's parent pathname or {@code null}.
*/
public String getParent() {
int length = path.length(), firstInPath = 0;
if (separatorChar == '\\' && length > 2 && path.charAt(1) == ':') {
firstInPath = 2;
}
int index = path.lastIndexOf(separatorChar);
if (index == -1 && firstInPath > 0) {
index = 2;
}
if (index == -1 || path.charAt(length - 1) == separatorChar) {
return null;
}
if (path.indexOf(separatorChar) == index
&& path.charAt(firstInPath) == separatorChar) {
return path.substring(0, index + 1);
}
return path.substring(0, index);
}
/**
* Returns a new file made from the pathname of the parent of this file.
* This is the path up to but not including the last name. {@code null} is
* returned when there is no parent.
*
* @return a new file representing this file's parent or {@code null}.
*/
public File getParentFile() {
String tempParent = getParent();
if (tempParent == null) {
return null;
}
return new File(tempParent);
}
/**
* Returns the path of this file.
*
* @return this file's path.
*/
public String getPath() {
return path;
}
/**
* Returns an integer hash code for the receiver. Any two objects for which
* {@code equals} returns {@code true} must return the same hash code.
*
* @return this files's hash value.
* @see #equals
*/
@Override
public int hashCode() {
return getPath().hashCode() ^ 1234321;
}
/**
* Indicates if this file's pathname is absolute. Whether a pathname is
* absolute is platform specific. On Android, absolute paths start with
* the character '/'.
*
* @return {@code true} if this file's pathname is absolute, {@code false}
* otherwise.
* @see #getPath
*/
public boolean isAbsolute() {
return path.length() > 0 && path.charAt(0) == separatorChar;
}
/**
* Indicates if this file represents a <em>directory</em> on the
* underlying file system.
*
* @return {@code true} if this file is a directory, {@code false}
* otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
*/
public boolean isDirectory() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return isDirectoryImpl(pathBytes);
}
private native boolean isDirectoryImpl(byte[] filePath);
/**
* Indicates if this file represents a <em>file</em> on the underlying
* file system.
*
* @return {@code true} if this file is a file, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
*/
public boolean isFile() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return isFileImpl(pathBytes);
}
private native boolean isFileImpl(byte[] filePath);
/**
* Returns whether or not this file is a hidden file as defined by the
* operating system. The notion of "hidden" is system-dependent. For Unix
* systems a file is considered hidden if its name starts with a ".". For
* Windows systems there is an explicit flag in the file system for this
* purpose.
*
* @return {@code true} if the file is hidden, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
*/
public boolean isHidden() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return getName().startsWith(".");
}
/**
* Returns the time when this file was last modified, measured in
* milliseconds since January 1st, 1970, midnight.
* Returns 0 if the file does not exist.
*
* @return the time when this file was last modified.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
*/
public long lastModified() {
if (path.length() == 0) {
return 0;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return lastModifiedImpl(pathBytes);
}
private native long lastModifiedImpl(byte[] filePath);
/**
* Sets the time this file was last modified, measured in milliseconds since
* January 1st, 1970, midnight.
*
* @param time
* the last modification time for this file.
* @return {@code true} if the operation is successful, {@code false}
* otherwise.
* @throws IllegalArgumentException
* if {@code time < 0}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access to this file.
*/
public boolean setLastModified(long time) {
if (path.length() == 0) {
return false;
}
if (time < 0) {
throw new IllegalArgumentException(Msg.getString("K006a")); //$NON-NLS-1$
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
}
return setLastModifiedImpl(pathBytes, time);
}
private native boolean setLastModifiedImpl(byte[] path, long time);
/**
* Marks this file or directory to be read-only as defined by the operating
* system.
*
* @return {@code true} if the operation is successful, {@code false}
* otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access to this file.
*/
public boolean setReadOnly() {
if (path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
}
return setReadOnlyImpl(pathBytes);
}
private native boolean setReadOnlyImpl(byte[] path);
/**
* Returns the length of this file in bytes.
* Returns 0 if the file does not exist.
* The result for a directory is not defined.
*
* @return the number of bytes in this file.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
*/
public long length() {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
return lengthImpl(pathBytes);
}
private native long lengthImpl(byte[] filePath);
/**
* Returns an array of strings with the file names in the directory
* represented by this file. The result is {@code null} if this file is not
* a directory.
* <p>
* The entries {@code .} and {@code ..} representing the current and parent
* directory are not returned as part of the list.
*
* @return an array of strings with file names or {@code null}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #isDirectory
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
*/
public String[] list() {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(path);
}
if (path.length() == 0) {
return null;
}
return listImpl(pathBytes);
}
private native String[] listImpl(byte[] path);
/**
* Gets a list of the files in the directory represented by this file. This
* list is then filtered through a FilenameFilter and the names of files
* with matching names are returned as an array of strings. Returns
* {@code null} if this file is not a directory. If {@code filter} is
* {@code null} then all filenames match.
* <p>
* The entries {@code .} and {@code ..} representing the current and parent
* directories are not returned as part of the list.
*
* @param filter
* the filter to match names against, may be {@code null}.
* @return an array of files or {@code null}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #getPath
* @see #isDirectory
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
*/
public String[] list(FilenameFilter filter) {
String[] filenames = list();
if (filter == null || filenames == null) {
return filenames;
}
List<String> result = new ArrayList<String>(filenames.length);
for (String filename : filenames) {
if (filter.accept(this, filename)) {
result.add(filename);
}
}
return result.toArray(new String[result.size()]);
}
/**
* Returns an array of files contained in the directory represented by this
* file. The result is {@code null} if this file is not a directory. The
* paths of the files in the array are absolute if the path of this file is
* absolute, they are relative otherwise.
*
* @return an array of files or {@code null}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #list
* @see #isDirectory
*/
public File[] listFiles() {
return filenamesToFiles(list());
}
/**
* Gets a list of the files in the directory represented by this file. This
* list is then filtered through a FilenameFilter and files with matching
* names are returned as an array of files. Returns {@code null} if this
* file is not a directory. If {@code filter} is {@code null} then all
* filenames match.
* <p>
* The entries {@code .} and {@code ..} representing the current and parent
* directories are not returned as part of the list.
*
* @param filter
* the filter to match names against, may be {@code null}.
* @return an array of files or {@code null}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #list(FilenameFilter filter)
* @see #getPath
* @see #isDirectory
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
*/
public File[] listFiles(FilenameFilter filter) {
return filenamesToFiles(list(filter));
}
/**
* Gets a list of the files in the directory represented by this file. This
* list is then filtered through a FileFilter and matching files are
* returned as an array of files. Returns {@code null} if this file is not a
* directory. If {@code filter} is {@code null} then all files match.
* <p>
* The entries {@code .} and {@code ..} representing the current and parent
* directories are not returned as part of the list.
*
* @param filter
* the filter to match names against, may be {@code null}.
* @return an array of files or {@code null}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies read
* access to this file.
* @see #getPath
* @see #isDirectory
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
*/
public File[] listFiles(FileFilter filter) {
File[] files = listFiles();
if (filter == null || files == null) {
return files;
}
List<File> result = new ArrayList<File>(files.length);
for (File file : files) {
if (filter.accept(file)) {
result.add(file);
}
}
return result.toArray(new File[result.size()]);
}
/**
* Converts a String[] containing filenames to a File[].
* Note that the filenames must not contain slashes.
* This method is to remove duplication in the implementation
* of File.list's overloads.
*/
private File[] filenamesToFiles(String[] filenames) {
if (filenames == null) {
return null;
}
int count = filenames.length;
File[] result = new File[count];
for (int i = 0; i < count; ++i) {
result[i] = new File(this, filenames[i]);
}
return result;
}
/**
* Creates the directory named by the trailing filename of this file. Does
* not create the complete path required to create this directory.
*
* @return {@code true} if the directory has been created, {@code false}
* otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access for this file.
* @see #mkdirs
*/
public boolean mkdir() {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
}
return mkdirImpl(pathBytes);
}
private native boolean mkdirImpl(byte[] filePath);
/**
* Creates the directory named by the trailing filename of this file,
* including the complete directory path required to create this directory.
*
* @return {@code true} if the necessary directories have been created,
* {@code false} if the target directory already exists or one of
* the directories can not be created.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access for this file.
* @see #mkdir
*/
public boolean mkdirs() {
/* If the terminal directory already exists, answer false */
if (exists()) {
return false;
}
/* If the receiver can be created, answer true */
if (mkdir()) {
return true;
}
String parentDir = getParent();
/* If there is no parent and we were not created, answer false */
if (parentDir == null) {
return false;
}
/* Otherwise, try to create a parent directory and then this directory */
return (new File(parentDir).mkdirs() && mkdir());
}
/**
* Creates a new, empty file on the file system according to the path
* information stored in this file.
*
* @return {@code true} if the file has been created, {@code false} if it
* already exists.
* @throws IOException if it's not possible to create the file.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access for this file.
*/
public boolean createNewFile() throws IOException {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
}
if (path.length() == 0) {
throw new IOException(Msg.getString("KA012")); //$NON-NLS-1$
}
return createNewFileImpl(pathBytes);
}
private native boolean createNewFileImpl(byte[] filePath);
/**
* Creates an empty temporary file using the given prefix and suffix as part
* of the file name. If suffix is {@code null}, {@code .tmp} is used. This
* method is a convenience method that calls
* {@link #createTempFile(String, String, File)} with the third argument
* being {@code null}.
*
* @param prefix
* the prefix to the temp file name.
* @param suffix
* the suffix to the temp file name.
* @return the temporary file.
* @throws IOException
* if an error occurs when writing the file.
*/
public static File createTempFile(String prefix, String suffix)
throws IOException {
return createTempFile(prefix, suffix, null);
}
/**
* Creates an empty temporary file in the given directory using the given
* prefix and suffix as part of the file name.
*
* @param prefix
* the prefix to the temp file name.
* @param suffix
* the suffix to the temp file name.
* @param directory
* the location to which the temp file is to be written, or
* {@code null} for the default location for temporary files,
* which is taken from the "java.io.tmpdir" system property. It
* may be necessary to set this property to an existing, writable
* directory for this method to work properly.
* @return the temporary file.
* @throws IllegalArgumentException
* if the length of {@code prefix} is less than 3.
* @throws IOException
* if an error occurs when writing the file.
*/
@SuppressWarnings("nls")
public static File createTempFile(String prefix, String suffix,
File directory) throws IOException {
// Force a prefix null check first
if (prefix.length() < 3) {
throw new IllegalArgumentException(Msg.getString("K006b"));
}
String newSuffix = suffix == null ? ".tmp" : suffix;
File tmpDirFile;
if (directory == null) {
String tmpDir = AccessController.doPrivileged(
new PriviAction<String>("java.io.tmpdir", "."));
tmpDirFile = new File(tmpDir);
} else {
tmpDirFile = directory;
}
File result;
do {
result = genTempFile(prefix, newSuffix, tmpDirFile);
} while (!result.createNewFile());
return result;
}
private static File genTempFile(String prefix, String suffix, File directory) {
if (counter == 0) {
// TODO: this doesn't make a lot of sense. SecureRandom for the seed, but then always just add one?
int newInt = new SecureRandom().nextInt();
counter = ((newInt / 65535) & 0xFFFF) + 0x2710;
}
StringBuilder newName = new StringBuilder();
newName.append(prefix);
newName.append(counter++);
newName.append(suffix);
return new File(directory, newName.toString());
}
/**
* Renames this file to the name represented by the {@code dest} file. This
* works for both normal files and directories.
*
* @param dest
* the file containing the new name.
* @return {@code true} if the File was renamed, {@code false} otherwise.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies write
* access for this file or the {@code dest} file.
*/
public boolean renameTo(java.io.File dest) {
if (path.length() == 0 || dest.path.length() == 0) {
return false;
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkWrite(path);
security.checkWrite(dest.path);
}
return renameToImpl(pathBytes, dest.pathBytes);
}
private native boolean renameToImpl(byte[] pathExist, byte[] pathNew);
/**
* Returns a string containing a concise, human-readable description of this
* file.
*
* @return a printable representation of this file.
*/
@Override
public String toString() {
return path;
}
/**
* Returns a Uniform Resource Identifier for this file. The URI is system
* dependent and may not be transferable between different operating / file
* systems.
*
* @return an URI for this file.
*/
@SuppressWarnings("nls")
public URI toURI() {
String name = getAbsoluteName();
try {
if (!name.startsWith("/")) {
// start with sep.
return new URI("file", null, new StringBuilder(
name.length() + 1).append('/').append(name).toString(),
null, null);
} else if (name.startsWith("//")) {
return new URI("file", "", name, null); // UNC path
}
return new URI("file", null, name, null, null);
} catch (URISyntaxException e) {
// this should never happen
return null;
}
}
/**
* Returns a Uniform Resource Locator for this file. The URL is system
* dependent and may not be transferable between different operating / file
* systems.
*
* @return a URL for this file.
* @throws java.net.MalformedURLException
* if the path cannot be transformed into a URL.
*/
@SuppressWarnings("nls")
public URL toURL() throws java.net.MalformedURLException {
String name = getAbsoluteName();
if (!name.startsWith("/")) {
// start with sep.
return new URL(
"file", EMPTY_STRING, -1, new StringBuilder(name.length() + 1) //$NON-NLS-1$
.append('/').append(name).toString(), null);
} else if (name.startsWith("//")) {
return new URL("file:" + name); // UNC path
}
return new URL("file", EMPTY_STRING, -1, name, null);
}
private String getAbsoluteName() {
File f = getAbsoluteFile();
String name = f.getPath();
if (f.isDirectory() && name.charAt(name.length() - 1) != separatorChar) {
// Directories must end with a slash
name = new StringBuilder(name.length() + 1).append(name)
.append('/').toString();
}
if (separatorChar != '/') { // Must convert slashes.
name = name.replace(separatorChar, '/');
}
return name;
}
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
stream.writeChar(separatorChar);
}
private void readObject(ObjectInputStream stream) throws IOException,
ClassNotFoundException {
stream.defaultReadObject();
char inSeparator = stream.readChar();
init(path.replace(inSeparator, separatorChar));
}
}