java.lang.Object
java.io.Writer
java.io.PrintWriter
Print formatted representations of objects to a text-output stream. This class implements all of the print methods found in PrintStream. It does not contain methods for writing raw bytes, for which a program should use unencoded byte streams.
Unlike the PrintStream class, if automatic flushing is enabled it will be done only when one of the println() methods is invoked, rather than whenever a newline character happens to be output. The println() methods use the platform's own notion of line separator rather than the newline character.
Methods in this class never throw I/O exceptions. The client may inquire as to whether any errors have occurred by invoking checkError().
Field Summary | |
protected
Writer |
out
The underlying character-output stream of this PrintWriter . |
Fields inherited from class java.io.Writer |
lock |
Constructor Summary | |
PrintWriter(OutputStream out) Create a new PrintWriter, without automatic line flushing, from an existing OutputStream. |
|
PrintWriter(OutputStream out,
boolean autoFlush) Create a new PrintWriter from an existing OutputStream. |
|
PrintWriter(Writer out) Create a new PrintWriter, without automatic line flushing. |
|
PrintWriter(Writer out, boolean autoFlush)
Create a new PrintWriter. |
Method Summary | |
boolean |
checkError()
Flush the stream if it's not closed and check its error state. |
void |
close()
Close the stream. |
void |
flush()
Flush the stream. |
void |
print(boolean b)
Print a boolean value. |
void |
print(char c)
Print a character. |
void |
print(char[] s)
Print an array of characters. |
void |
print(double d)
Print a double-precision floating-point number. |
void |
print(float f)
Print a floating-point number. |
void |
print(int i)
Print an integer. |
void |
print(long l)
Print a long integer. |
void |
print(Object obj) Print an object. |
void |
print(String s) Print a string. |
void |
println()
Terminate the current line by writing the line separator string. |
void |
println(boolean x)
Print a boolean value and then terminate the line. |
void |
println(char x)
Print a character and then terminate the line. |
void |
println(char[] x)
Print an array of characters and then terminate the line. |
void |
println(double x)
Print a double-precision floating-point number and then terminate the line. |
void |
println(float x)
Print a floating-point number and then terminate the line. |
void |
println(int x)
Print an integer and then terminate the line. |
void |
println(long x)
Print a long integer and then terminate the line. |
void |
println(Object x) Print an Object and then terminate the line. |
void |
println(String x) Print a String and then terminate the line. |
protected
void |
setError()
Indicate that an error has occurred. |
void |
write(char[] buf)
Write an array of characters. |
void |
write(char[] buf,
int off,
int len) Write a portion of an array of characters. |
void |
write(int c)
Write a single character. |
void |
write(String s) Write a string. |
void |
write(String s, int off,
int len) Write a portion of a string. |
Methods inherited from class java.lang.Object |
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait |
Field Detail |
protected Writer out
PrintWriter
.
Constructor Detail |
public PrintWriter(Writer out)
out
- A character-output streampublic PrintWriter(Writer out,
boolean autoFlush)
out
- A character-output streamautoFlush
- A boolean; if true, the println()
methods will flush the output bufferpublic PrintWriter(OutputStream out)
out
- An output streamOutputStreamWriter.OutputStreamWriter(java.io.OutputStream)
public PrintWriter(OutputStream out,
boolean autoFlush)
out
- An output streamautoFlush
- A boolean; if true, the println()
methods will flush the output bufferOutputStreamWriter.OutputStreamWriter(java.io.OutputStream)
Method Detail |
public void flush()
flush
in class Writer
checkError()
public void close()
close
in class Writer
checkError()
public boolean checkError()
protected void setError()
public void write(int c)
write
in class Writer
c
- int specifying a character to be written.public void write(char[] buf,
int off,
int len)
write
in class Writer
buf
- Array of charactersoff
- Offset from which to start writing
characterslen
- Number of characters to writepublic void write(char[] buf)
write
in class Writer
buf
- Array of characters to be writtenpublic void write(String s,
int off,
int len)
write
in class Writer
s
- A Stringoff
- Offset from which to start writing
characterslen
- Number of characters to writepublic void write(String s)
write
in class Writer
s
- String to be writtenpublic void print(boolean b)
String.valueOf(boolean)
is translated into bytes according to the platform's default character
encoding, and these bytes are written in exactly the manner of the write(int)
method.
b
- The boolean
to be printedpublic void print(char c)
write(int)
method.
c
- The char
to be printedpublic void print(int i)
String.valueOf(int)
is translated into bytes according to the platform's default character
encoding, and these bytes are written in exactly the manner of the write(int)
method.
i
- The int
to be printedInteger.toString(int)
public void print(long l)
String.valueOf(long)
is translated into bytes according to the platform's default character
encoding, and these bytes are written in exactly the manner of the write(int)
method.
l
- The long
to be printedLong.toString(long)
public void print(float f)
String.valueOf(float)
is translated into bytes according to the platform's default character
encoding, and these bytes are written in exactly the manner of the write(int)
method.
f
- The float
to be printedFloat.toString(float)
public void print(double d)
String.valueOf(double)
is translated into bytes according to the platform's default character
encoding, and these bytes are written in exactly the manner of the write(int)
method.
d
- The double
to be printedDouble.toString(double)
public void print(char[] s)
write(int)
method.
s
- The array of chars to be printed NullPointerException
- If s
is null
public void print(String s)
null
then the
string "null"
is printed. Otherwise, the string's
characters are converted into bytes according to the platform's default
character encoding, and these bytes are written in exactly the manner
of the write(int)
method.
s
- The String
to be printedpublic void print(Object obj)
String.valueOf(Object)
method is translated into bytes according to the platform's default
character encoding, and these bytes are written in exactly the manner
of the write(int)
method.
obj
- The Object
to be printedObject.toString()
public void println()
line.separator
,
and
is not necessarily a single newline character ('\n'
).
public void println(boolean x)
print(boolean)
and then println()
.
x
- the boolean
value to be printedpublic void println(char x)
print(char)
and then println()
.
x
- the char
value to be printedpublic void println(int x)
print(int)
and then println()
.
x
- the int
value to be printedpublic void println(long x)
print(long)
and then println()
.
x
- the long
value to be printedpublic void println(float x)
print(float)
and then println()
.
x
- the float
value to be printedpublic void println(double x)
print(double)
and then println()
.
x
- the double
value to be printedpublic void println(char[] x)
print(char[])
and then println()
.
x
- the array of char
values to be
printedpublic void println(String x)
print(String)
and then println()
.
x
- the String
value to be printedpublic void println(Object x)
print(Object)
and then println()
.
x
- the Object
value to be printed