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Class FileReader

java.lang.Object
java.io.Reader
java.io.InputStreamReader
java.io.FileReader
All Implemented Interfaces:
Closeable, AutoCloseable, Readable
public class FileReader extends InputStreamReader
Reads text from character files using a default buffer size. Decoding from bytes to characters uses either a specified charset or the default charset.

The FileReader is meant for reading streams of characters. For reading streams of raw bytes, consider using a FileInputStream.

Since:
1.1
See Also:
  • InputStreamReader
  • FileInputStream
  • Charset.defaultCharset()

Field Summary

Fields declared in class Reader

lock
Modifier and Type Field Description
protected Object lock
The object used to synchronize operations on this stream.

Constructor Summary

Constructor Description
FileReader(File file)
Creates a new FileReader, given the File to read, using the default charset.
FileReader(FileDescriptor fd)
Creates a new FileReader, given the FileDescriptor to read, using the default charset.
FileReader(File file, Charset charset)
Creates a new FileReader, given the File to read and the charset.
FileReader(String fileName)
Creates a new FileReader, given the name of the file to read, using the default charset.
FileReader(String fileName, Charset charset)
Creates a new FileReader, given the name of the file to read and the charset.

Method Summary

Methods declared in class InputStreamReader

close, getEncoding, read, read, ready
Modifier and Type Method Description
void close()
Closes the stream and releases any system resources associated with it.
String getEncoding()
Returns the name of the character encoding being used by this stream.
int read()
Reads a single character.
int read(char[] cbuf, int off, int len)
Reads characters into a portion of an array.
boolean ready()
Tells whether this stream is ready to be read.

Methods declared in class Reader

mark, markSupported, nullReader, of, read, read, readAllAsString, readAllLines, reset, skip, transferTo
Modifier and Type Method Description
void mark(int readAheadLimit)
Marks the present position in the stream.
boolean markSupported()
Tells whether this stream supports the mark() operation.
static Reader nullReader()
Returns a new Reader that reads no characters.
static Reader of(CharSequence cs)
Returns a Reader that reads characters from a CharSequence.
int read(char[] cbuf)
Reads characters into an array.
int read(CharBuffer target)
Attempts to read characters into the specified character buffer.
String readAllAsString()
Reads all remaining characters into a string.
List<String> readAllLines()
Reads all remaining characters as lines of text.
void reset()
Resets the stream.
long skip(long n)
Skips characters.
long transferTo(Writer out)
Reads all characters from this reader and writes the characters to the given writer in the order that they are read.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Modifier and Type Method Description
protected Object clone()
Creates and returns a copy of this object.
boolean equals(Object obj)
Indicates whether some other object is "equal to" this one.
protected void finalize()
Deprecated, for removal: This API element is subject to removal in a future version.
Finalization is deprecated and subject to removal in a future release.
final Class<?> getClass()
Returns the runtime class of this Object.
int hashCode()
Returns a hash code value for this object.
final void notify()
Wakes up a single thread that is waiting on this object's monitor.
final void notifyAll()
Wakes up all threads that are waiting on this object's monitor.
String toString()
Returns a string representation of the object.
final void wait()
Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
final void wait(long timeoutMillis)
Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
final void wait(long timeoutMillis, int nanos)
Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

FileReader

public FileReader(String fileName) throws FileNotFoundException
Creates a new FileReader, given the name of the file to read, using the default charset.
Parameters:
fileName - the name of the file to read
Throws:
FileNotFoundException - if the named file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
See Also:
  • Charset.defaultCharset()

FileReader

public FileReader(File file) throws FileNotFoundException
Creates a new FileReader, given the File to read, using the default charset.
Parameters:
file - the File to read
Throws:
FileNotFoundException - if the file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
See Also:
  • Charset.defaultCharset()

FileReader

public FileReader(FileDescriptor fd)
Creates a new FileReader, given the FileDescriptor to read, using the default charset.
Parameters:
fd - the FileDescriptor to read
See Also:
  • Charset.defaultCharset()

FileReader

public FileReader(String fileName, Charset charset) throws IOException
Creates a new FileReader, given the name of the file to read and the charset.
Parameters:
fileName - the name of the file to read
charset - the charset
Throws:
IOException - if the named file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
Since:
11

FileReader

public FileReader(File file, Charset charset) throws IOException
Creates a new FileReader, given the File to read and the charset.
Parameters:
file - the File to read
charset - the charset
Throws:
IOException - if the file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
Since:
11

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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