Print writer

Print writer

public class PrintWriter extends Writer

The Java.io.PrintWriter class prints formatted representations of objects to a text-output stream.

Class declaration

Following is the declaration for Java.io.PrintWriter class:
public class PrintWriter
  extends Writer

Field

Following are the fields for Java.io.PrintWriter class:


protected Writer out -- This is the character-output stream of this PrintWriter.


protected Object lock -- This is the object used to synchronize operations on this stream.



Class constructors

S.N.
Constructor & Description
1

PrintWriter(File file)

This creates a new PrintWriter, without automatic line flushing, with the specified file.

2

PrintWriter(File file, String csn)

This creates a new PrintWriter, without automatic line flushing, with the specified file and charset.

3

PrintWriter(OutputStream out)

This creates a new PrintWriter, without automatic line flushing, from an existing OutputStream.

4

PrintWriter(OutputStream out, boolean autoFlush)

This creates a new PrintWriter from an existing OutputStream.

5

PrintWriter(String fileName)

This creates a new PrintWriter, without automatic line flushing, with the specified file name.

6

PrintWriter(String fileName, String csn)

This creates a new PrintWriter, without automatic line flushing, with the specified file name and charset.

7

PrintWriter(Writer out)

This creates a new PrintWriter, without automatic line flushing.

8

PrintWriter(Writer out, boolean autoFlush)

This creates a new PrintWriter.



Class methods

S.N.
Method & Description
1

PrintWriter append(char c)

This method appends the specified character to this writer.

2

PrintWriter append(CharSequence csq)

This method appends the specified character sequence to this writer.

3

PrintWriter append(CharSequence csq, int start, int end)

This method appends a subsequence of the specified character sequence to this writer.

4

boolean checkError()

This method flushes the stream if it's not closed and checks its error state.

5

protected void clearError()

This method Clears the error state of this stream.

6

void close()

This method Closes the stream and releases any system resources associated with it.

7

void flush()

This method Flushes the stream.

8

PrintWriter format(Locale l, String format, Object... args)

This method writes a formatted string to this writer using the specified format string and arguments.

9

PrintWriter format(String format, Object... args)

This method writes a formatted string to this writer using the specified format string and arguments.

10

void print(boolean b)

This method prints a boolean value.

11

void print(char c)

This method prints a character.

12

void print(char[] s)

This method Prints an array of characters.

13

void print(double d)

This method Prints a double-precision floating-point number.

14

void print(float f)

This method prints a floating-point number.

15

void print(int i)

This method prints an integer.

16

void print(long l)

This method prints a long integer.

17

void print(Object obj)

This method prints an object.

18

void print(String s)

This method prints a string.

19

PrintWriter printf(Locale l, String format, Object... args)

This is a convenience method to write a formatted string to this writer using the specified format string and arguments.

20

PrintWriter printf(String format, Object... args)

This is a convenience method to write a formatted string to this writer using the specified format string and arguments.

21

void println()

This method terminates the current line by writing the line separator string.

22

void println(boolean x)

This method prints a boolean value and then terminates the line.

23

void println(char x)

This method prints a character and then terminates the line.

24

void println(char[] x)

This method prints an array of characters and then terminates the line.

25

void println(double x)

This method prints a double-precision floating-point number and then terminates the line.

26

void println(float x)

This method prints a floating-point number and then terminates the line.

27

void println(int x)

This method prints an integer and then terminates the line.

28

void println(long x)

This method prints a long integer and then terminates the line.

29

void println(Object x)

This method prints an Object and then terminates the line.

30

void println(String x)

This method prints a String and then terminates the line.

31

protected void setError()

This method indicates that an error has occurred.

32

void write(char[] buf)

This method writes an array of characters.

33

void write(char[] buf, int off, int len)

This method writes a portion of an array of characters.

34

void write(int c)

This methodWrites a single character.

35

void write(String s)

This method writes a string.

36

void write(String s, int off, int len)

This method writes a portion of a string.


Example,

import java.io.*;
import java.util.Date;

public class PrintWriterDemo {

   public static void main(String[] args) {
      Object obj1 = "Object";
      Object obj2 = 2;
      Date date = new Date(112, 2, 21);
      try {

         // create a new writer
         PrintWriter pw = new PrintWriter(System.out);

         // print object
         pw.println(obj1);

         // print another object
         pw.println(obj2);

         // print a date (it is an object)
         pw.print(date);

         // flush the writer
         pw.flush();

      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }
}

Let us compile and run the above program, this will produce the following result:
Object
2
Wed Mar 21 00:00:00 EET 2012