Java IO.pdf - Nguyen Dang Binh

There are four constructors in this class:
public PrintWriter(Writer out)
public PrintWriter(Writer out, boolean autoFlush)
public PrintWriter(OutputStream out)
public PrintWriter(OutputStream out, boolean autoFlush)
Java I/O
The PrintWriter can send text either to an output stream or to another writer. If autoFlush
is set to true, the PrintWriter is flushed every time println() is invoked.
The PrintWriter class implements the abstract write() method from java.io.Writer and
overrides five other methods:
public void write(int c)
public void write(char[] text)
public void write(String s)
public void write(String s, int offset, int length)
public void flush()
public void close()
These methods are used almost identically to their equivalents in any other Writer class. The
one difference is that none of them throw IOExceptions; in fact, no method in the
PrintWriter class ever throws an IOException. If the underlying output stream or writer
throws an IOException, it's caught inside PrintWriter and an error flag is set. Read the
status of this flag with the checkError() method:
public boolean checkError()
Since checkError() returns a boolean, it only tells you that an I/O error has occurred; it
does not tell you what that error was. Furthermore, once an error has occurred, checkError()
always returns true—there is no way to reset it so you can test for later errors. On the other
hand, you can indicate that an error has occurred with setError():
protected void setError()
The main advantages of the PrintWriter class are the nine-way overloaded print() method
and the 10-way overloaded println() method. Any Java object, variable, or literal can be
printed by passing it to a print() or println() method. The println() method follows its
argument with a platform-dependent line separator (such as \r\n) and then flushes the output
if autoFlush is enabled. The print() method does not. Otherwise, these methods are the
same.
public void print(boolean b)
public void print(char c)
public void print(int i)
public void print(long l)
public void print(float f)
public void print(double d)
public void print(char[] text)
public void print(String s)
public void print(Object obj)
public void println()
public void println(boolean b)
public void println(char c)
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