Class Writer

java.lang.Object
java.io.Writer
All Implemented Interfaces:
Closeable, Flushable, Appendable, AutoCloseable
Direct Known Subclasses:
BufferedWriter, OutputStreamWriter, PrintWriter, StringWriter

public abstract class Writer extends Object implements Appendable, Closeable, Flushable
Abstract class for writing to character streams. The only methods that a subclass must implement are write(char[], int, int), flush(), and close(). Most subclasses, however, will override some of the methods defined here in order to provide higher efficiency, additional functionality, or both. Since: JDK1.1, CLDC 1.0 See Also:OutputStreamWriter, Reader
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected Object
    The object used to synchronize operations on this stream.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    Create a new character-stream writer whose critical sections will synchronize on the writer itself.
    protected
    Writer(Object lock)
    Create a new character-stream writer whose critical sections will synchronize on the given object.
  • Method Summary

    Modifier and Type
    Method
    Description
    append(char c)
    Writes c.
    Writes csq, or "null" when it is null.
    append(CharSequence csq, int start, int end)
    Writes the characters of csq from start up to end.
    abstract void
    Close the stream, flushing it first.
    abstract void
    Flush the stream.
    void
    write(char[] cbuf)
    Write an array of characters.
    abstract void
    write(char[] cbuf, int off, int len)
    Write a portion of an array of characters.
    void
    write(int c)
    Write a single character.
    void
    Write a string.
    void
    write(String str, int off, int len)
    Write a portion of a string.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

    • lock

      protected Object lock
      The object used to synchronize operations on this stream. For efficiency, a character-stream object may use an object other than itself to protect critical sections. A subclass should therefore use the object in this field rather than this or a synchronized method.
  • Constructor Details

    • Writer

      protected Writer()
      Create a new character-stream writer whose critical sections will synchronize on the writer itself.
    • Writer

      protected Writer(Object lock)
      Create a new character-stream writer whose critical sections will synchronize on the given object. lock - Object to synchronize on.
  • Method Details

    • append

      public Writer append(CharSequence csq) throws IOException
      Writes csq, or "null" when it is null.
      Specified by:
      append in interface Appendable
      Throws:
      IOException
    • append

      public Writer append(char c) throws IOException
      Writes c.
      Specified by:
      append in interface Appendable
      Throws:
      IOException
    • append

      public Writer append(CharSequence csq, int start, int end) throws IOException
      Writes the characters of csq from start up to end.
      Specified by:
      append in interface Appendable
      Throws:
      IOException
    • close

      public abstract void close() throws IOException
      Close the stream, flushing it first. Once a stream has been closed, further write() or flush() invocations will cause an IOException to be thrown. Closing a previously-closed stream, however, has no effect.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException
    • flush

      public abstract void flush() throws IOException
      Flush the stream. If the stream has saved any characters from the various write() methods in a buffer, write them immediately to their intended destination. Then, if that destination is another character or byte stream, flush it. Thus one flush() invocation will flush all the buffers in a chain of Writers and OutputStreams.
      Specified by:
      flush in interface Flushable
      Throws:
      IOException
    • write

      public void write(char[] cbuf) throws IOException
      Write an array of characters.
      Throws:
      IOException
    • write

      public abstract void write(char[] cbuf, int off, int len) throws IOException
      Write a portion of an array of characters.
      Throws:
      IOException
    • write

      public void write(int c) throws IOException
      Write a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored. Subclasses that intend to support efficient single-character output should override this method.
      Throws:
      IOException
    • write

      public void write(String str) throws IOException
      Write a string.
      Throws:
      IOException
    • write

      public void write(String str, int off, int len) throws IOException
      Write a portion of a string.
      Throws:
      IOException