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Since: API Level 1

public class

PrintStream

extends FilterOutputStream
implements Closeable Appendable

java.lang.Object
↳	java.io.OutputStream
	↳	java.io.FilterOutputStream
		↳	java.io.PrintStream

Class Overview

Wraps an existing OutputStream and provides convenience methods for writing common data types in a human readable format. This is not to be confused with DataOutputStream which is used for encoding common data types so that they can be read back in. No IOException is thrown by this class. Instead, callers should use checkError() to see if a problem has occurred in this stream.

Summary

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Inherited Fields

From class java.io.FilterOutputStream

Public Constructors
	PrintStream(OutputStream out) Constructs a new `PrintStream` with `out` as its target stream.
	PrintStream(OutputStream out, boolean autoFlush) Constructs a new `PrintStream` with `out` as its target stream.
	PrintStream(OutputStream out, boolean autoFlush, String enc) Constructs a new `PrintStream` with `out` as its target stream and using the character encoding `enc` while writing.
	PrintStream(File file) Constructs a new `PrintStream` with `file` as its target.
	PrintStream(File file, String csn) Constructs a new `PrintStream` with `file` as its target.
	PrintStream(String fileName) Constructs a new `PrintStream` with the file identified by `fileName` as its target.
	PrintStream(String fileName, String csn) Constructs a new `PrintStream` with the file identified by `fileName` as its target.

Public Methods
PrintStream	append(char c) Appends the char `c`.
PrintStream	append(CharSequence charSequence, int start, int end) Appends a subsequence of CharSequence `charSequence`, or `"null"`.
PrintStream	append(CharSequence charSequence) Appends the CharSequence `charSequence`, or `"null"`.
boolean	checkError() Flushes this stream and returns the value of the error flag.
synchronized void	close() Closes this print stream.
synchronized void	flush() Ensures that all pending data is sent out to the target stream.
PrintStream	format(Locale l, String format, Object... args) Writes a string formatted by an intermediate `Formatter` to this stream using the specified locale, format string and arguments.
PrintStream	format(String format, Object... args) Formats `args` according to the format string `format`, and writes the result to this stream.
void	print(float f) Prints the string representation of the float `f`.
void	print(double d) Prints the string representation of the double `d`.
synchronized void	print(String str) Prints a string to the target stream.
void	print(Object o) Prints the string representation of the Object `o`, or `"null"`.
void	print(char c) Prints the string representation of the char `c`.
void	print(char[] chars) Prints the string representation of the character array `chars`.
void	print(long l) Prints the string representation of the long `l`.
void	print(int i) Prints the string representation of the int `i`.
void	print(boolean b) Prints the string representation of the boolean `b`.
PrintStream	printf(Locale l, String format, Object... args) Prints a formatted string.
PrintStream	printf(String format, Object... args) Prints a formatted string.
void	println() Prints a newline.
void	println(float f) Prints the string representation of the float `f` followed by a newline.
void	println(int i) Prints the string representation of the int `i` followed by a newline.
void	println(long l) Prints the string representation of the long `l` followed by a newline.
void	println(Object o) Prints the string representation of the Object `o`, or `"null"`, followed by a newline.
void	println(char[] chars) Prints the string representation of the character array `chars` followed by a newline.
synchronized void	println(String str) Prints a string followed by a newline.
void	println(char c) Prints the string representation of the char `c` followed by a newline.
void	println(double d) Prints the string representation of the double `d` followed by a newline.
void	println(boolean b) Prints the string representation of the boolean `b` followed by a newline.
synchronized void	write(int oneByte) Writes one byte to the target stream.
void	write(byte[] buffer, int offset, int length) Writes `count` bytes from `buffer` starting at `offset` to the target stream.

Protected Methods
void	clearError() Sets the error state of the stream to false.
void	setError() Sets the error flag of this print stream to true.

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Inherited Methods

From class java.io.FilterOutputStream

From class java.io.OutputStream

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

From interface java.io.Closeable

From interface java.io.Flushable

From interface java.lang.Appendable

Public Constructors

public PrintStream (OutputStream out)

Since: API Level 1

Constructs a new PrintStream with out as its target stream. By default, the new print stream does not automatically flush its contents to the target stream when a newline is encountered.

Parameters

out	the target output stream.

Throws

NullPointerException	if `out` is `null`.

public PrintStream (OutputStream out, boolean autoFlush)

Since: API Level 1

Constructs a new PrintStream with out as its target stream. The parameter autoFlush determines if the print stream automatically flushes its contents to the target stream when a newline is encountered.

Parameters

out	the target output stream.
autoFlush	indicates whether to flush contents upon encountering a newline sequence.

Throws

NullPointerException	if `out` is `null`.

public PrintStream (OutputStream out, boolean autoFlush, String enc)

Since: API Level 1

Constructs a new PrintStream with out as its target stream and using the character encoding enc while writing. The parameter autoFlush determines if the print stream automatically flushes its contents to the target stream when a newline is encountered.

Parameters

out	the target output stream.
autoFlush	indicates whether or not to flush contents upon encountering a newline sequence.
enc	the non-null string describing the desired character encoding.

Throws

NullPointerException	if `out` or `enc` are `null`.
UnsupportedEncodingException	if the encoding specified by `enc` is not supported.

public PrintStream (File file)

Since: API Level 1

Constructs a new PrintStream with file as its target. The VM's default character set is used for character encoding.

Parameters

file	the target file. If the file already exists, its contents are removed, otherwise a new file is created.

Throws

FileNotFoundException	if an error occurs while opening or creating the target file.

public PrintStream (File file, String csn)

Since: API Level 1

Constructs a new PrintStream with file as its target. The character set named csn is used for character encoding.

Parameters

file	the target file. If the file already exists, its contents are removed, otherwise a new file is created.
csn	the name of the character set used for character encoding.

Throws

FileNotFoundException	if an error occurs while opening or creating the target file.
NullPointerException	if `csn` is `null`.
UnsupportedEncodingException	if the encoding specified by `csn` is not supported.

public PrintStream (String fileName)

Since: API Level 1

Constructs a new PrintStream with the file identified by fileName as its target. The VM's default character set is used for character encoding.

Parameters

fileName	the target file's name. If the file already exists, its contents are removed, otherwise a new file is created.

Throws

FileNotFoundException	if an error occurs while opening or creating the target file.

public PrintStream (String fileName, String csn)

Since: API Level 1

Constructs a new PrintStream with the file identified by fileName as its target. The character set named csn is used for character encoding.

Parameters

fileName	the target file's name. If the file already exists, its contents are removed, otherwise a new file is created.
csn	the name of the character set used for character encoding.

Throws

FileNotFoundException	if an error occurs while opening or creating the target file.
NullPointerException	if `csn` is `null`.
UnsupportedEncodingException	if the encoding specified by `csn` is not supported.

Public Methods

public PrintStream append (char c)

Since: API Level 1

Appends the char c.

Parameters

c	the character to append.

Returns

this stream.

public PrintStream append (CharSequence charSequence, int start, int end)

Since: API Level 1

Appends a subsequence of CharSequence charSequence, or "null".

Parameters

charSequence	the character sequence appended to the target stream.
start	the index of the first char in the character sequence appended to the target stream.
end	the index of the character following the last character of the subsequence appended to the target stream.

Returns

this stream.

Throws

IndexOutOfBoundsException	if `start > end`, `start < 0`, `end < 0` or either `start` or `end` are greater or equal than the length of `charSequence`.

public PrintStream append (CharSequence charSequence)

Since: API Level 1

Appends the CharSequence charSequence, or "null".

Parameters

charSequence	the character sequence to append.

Returns

this stream.

public boolean checkError ()

Since: API Level 1

Flushes this stream and returns the value of the error flag.

Returns

true if either an IOException has been thrown previously or if setError() has been called; false otherwise.

public synchronized void close ()

Since: API Level 1

Closes this print stream. Flushes this stream and then closes the target stream. If an I/O error occurs, this stream's error state is set to true.

public synchronized void flush ()

Since: API Level 1

Ensures that all pending data is sent out to the target stream. It also flushes the target stream. If an I/O error occurs, this stream's error state is set to true.

public PrintStream format (Locale l, String format, Object... args)

Since: API Level 1

Writes a string formatted by an intermediate Formatter to this stream using the specified locale, format string and arguments.

Parameters

l	the locale used in the method. No localization will be applied if `l` is `null`.
format	the format string (see `format(String, Object...)`)
args	the list of arguments passed to the formatter. If there are more arguments than required by `format`, additional arguments are ignored.

Returns

this stream.

Throws

IllegalFormatException	if the format string is illegal or incompatible with the arguments, if there are not enough arguments or if any other error regarding the format string or arguments is detected.
NullPointerException	if `format == null`

public PrintStream format (String format, Object... args)

Since: API Level 1

Formats args according to the format string format, and writes the result to this stream. This method uses the user's default locale. See "Be wary of the default locale".

Parameters

format	the format string (see `format(String, Object...)`)
args	the list of arguments passed to the formatter. If there are more arguments than required by `format`, additional arguments are ignored.

Returns

this stream.

Throws

IllegalFormatException	if the format string is illegal or incompatible with the arguments, if there are not enough arguments or if any other error regarding the format string or arguments is detected.
NullPointerException	if `format == null`

public void print (float f)

Since: API Level 1

Prints the string representation of the float f.

public void print (double d)

Since: API Level 1

Prints the string representation of the double d.

public synchronized void print (String str)

Since: API Level 1

Prints a string to the target stream. The string is converted to an array of bytes using the encoding chosen during the construction of this stream. The bytes are then written to the target stream with write(int).

If an I/O error occurs, this stream's error state is set to true.

Parameters

str	the string to print to the target stream.

public void print (Object o)

Since: API Level 1

Prints the string representation of the Object o, or "null".

public void print (char c)

Since: API Level 1

Prints the string representation of the char c.

public void print (char[] chars)

Since: API Level 1

Prints the string representation of the character array chars.

public void print (long l)

Since: API Level 1

Prints the string representation of the long l.

public void print (int i)

Since: API Level 1

Prints the string representation of the int i.

public void print (boolean b)

Since: API Level 1

Prints the string representation of the boolean b.

public PrintStream printf (Locale l, String format, Object... args)

Since: API Level 1

Prints a formatted string. The behavior of this method is the same as this stream's #format(Locale, String, Object...) method.

Parameters

l	the locale used in the method. No localization will be applied if `l` is `null`.
format	the format string (see `format(String, Object...)`)
args	the list of arguments passed to the formatter. If there are more arguments than required by `format`, additional arguments are ignored.

Returns

this stream.

Throws

IllegalFormatException	if the format string is illegal or incompatible with the arguments, if there are not enough arguments or if any other error regarding the format string or arguments is detected.
NullPointerException	if `format == null`.

public PrintStream printf (String format, Object... args)

Since: API Level 1

Prints a formatted string. The behavior of this method is the same as this stream's #format(String, Object...) method.

The Locale used is the user's default locale. See "Be wary of the default locale".

Parameters

format	the format string (see `format(String, Object...)`)
args	the list of arguments passed to the formatter. If there are more arguments than required by `format`, additional arguments are ignored.

Returns

this stream.

Throws

IllegalFormatException	if the format string is illegal or incompatible with the arguments, if there are not enough arguments or if any other error regarding the format string or arguments is detected.
NullPointerException	if `format == null`

public void println ()

Since: API Level 1

Prints a newline.

public void println (float f)

Since: API Level 1

Prints the string representation of the float f followed by a newline.

public void println (int i)

Since: API Level 1

Prints the string representation of the int i followed by a newline.

public void println (long l)

Since: API Level 1

Prints the string representation of the long l followed by a newline.

public void println (Object o)

Since: API Level 1

Prints the string representation of the Object o, or "null", followed by a newline.

public void println (char[] chars)

Since: API Level 1

Prints the string representation of the character array chars followed by a newline.

public synchronized void println (String str)

Since: API Level 1

Prints a string followed by a newline. The string is converted to an array of bytes using the encoding chosen during the construction of this stream. The bytes are then written to the target stream with write(int).

If an I/O error occurs, this stream's error state is set to true.

Parameters

str	the string to print to the target stream.

public void println (char c)

Since: API Level 1

Prints the string representation of the char c followed by a newline.

public void println (double d)

Since: API Level 1

Prints the string representation of the double d followed by a newline.

public void println (boolean b)

Since: API Level 1

Prints the string representation of the boolean b followed by a newline.

public synchronized void write (int oneByte)

Since: API Level 1

Writes one byte to the target stream. Only the least significant byte of the integer oneByte is written. This stream is flushed if oneByte is equal to the character '\n' and this stream is set to autoFlush.

This stream's error flag is set to true if it is closed or an I/O error occurs.

Parameters

oneByte	the byte to be written

public void write (byte[] buffer, int offset, int length)

Since: API Level 1

Writes count bytes from buffer starting at offset to the target stream. If autoFlush is set, this stream gets flushed after writing the buffer.

This stream's error flag is set to true if this stream is closed or an I/O error occurs.

Parameters

buffer	the buffer to be written.
offset	the index of the first byte in `buffer` to write.
length	the number of bytes in `buffer` to write.

Throws

IndexOutOfBoundsException	if `offset < 0` or `count < 0`, or if `offset + count` is bigger than the length of `buffer`.

Protected Methods

protected void clearError ()

Since: API Level 9

Sets the error state of the stream to false.

protected void setError ()

Since: API Level 1

Sets the error flag of this print stream to true.

Results

Interfaces

Classes

Exceptions

Errors

PrintStream

Class Overview

Summary

Public Constructors

public PrintStream (OutputStream out)

Parameters

Throws

public PrintStream (OutputStream out, boolean autoFlush)

Parameters

Throws

public PrintStream (OutputStream out, boolean autoFlush, String enc)

Parameters

Throws

public PrintStream (File file)

Parameters

Throws

public PrintStream (File file, String csn)

Parameters

Throws

public PrintStream (String fileName)

Parameters

Throws

public PrintStream (String fileName, String csn)

Parameters

Throws

Public Methods

public PrintStream append (char c)

Parameters

Returns

public PrintStream append (CharSequence charSequence, int start, int end)

Parameters

Returns

Throws

public PrintStream append (CharSequence charSequence)

Parameters

Returns

public boolean checkError ()

Returns

See Also

public synchronized void close ()

public synchronized void flush ()

public PrintStream format (Locale l, String format, Object... args)

Parameters

Returns

Throws

public PrintStream format (String format, Object... args)

Parameters

Returns

Throws

public void print (float f)

public void print (double d)

public synchronized void print (String str)

Parameters

See Also

public void print (Object o)

public void print (char c)

public void print (char[] chars)

public void print (long l)

public void print (int i)

public void print (boolean b)

public PrintStream printf (Locale l, String format, Object... args)

Parameters

Returns

Throws

public PrintStream printf (String format, Object... args)

Parameters

Returns

Throws

public void println ()

public void println (float f)

public void println (int i)

public void println (long l)

public void println (Object o)

public void println (char[] chars)

public synchronized void println (String str)