com.lf.commons.logging

Class LogPrintStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

java.io.PrintStream

com.lf.commons.logging.LogPrintStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.lang.Appendable, java.lang.AutoCloseable

public final class LogPrintStream
extends java.io.PrintStream

Receives data from an output stream and pipes it to the given logger.

Applications can utilize this I/O class to properly combine the code parts writing messages via System.out and System.err and the applications using loggers. Often programmers want all messages be written via logging (expecially exception stack traces). Normally standard output messages should be logged on the INFO level, those from the error channel should be logged on the WARNING level.

Remember that the print stream passed to the constructor is simply for proper startup. There are no messages passed on to this stream but only to the logging engine. The Javadoc comments of the methods are quite the same that can be found in the API documentation from SUN.

Since:

1.5

Version:

$Revision: 1.8 $, $Date: 2012/12/28 11:44:24 $

Author:

Axel Schwolow

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
LogPrintStream(java.util.logging.Logger logger, java.util.logging.Level level) Constructor.
LogPrintStream(java.util.logging.Logger logger, java.util.logging.Level level, java.lang.String id) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
java.io.PrintStream	append(char c) Appends the specified character to this output stream.
java.io.PrintStream	append(java.lang.CharSequence csq) Appends the specified character sequence to this output stream.
java.io.PrintStream	append(java.lang.CharSequence csq, int start, int end) Appends a subsequence of the specified character sequence to this output stream.
boolean	checkError() Flush the stream and check its error state.
void	close() Close the stream.
void	flush() Flush the stream.
java.io.PrintStream	format(java.util.Locale l, java.lang.String format, java.lang.Object... args) Writes a formatted string to this output stream using the specified format string and arguments.
java.io.PrintStream	format(java.lang.String format, java.lang.Object... args) Writes a formatted string to this output stream using the specified format string and arguments.
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(java.lang.Object obj) Print an object.
void	print(java.lang.String s) Print a string.
java.io.PrintStream	printf(java.util.Locale l, java.lang.String format, java.lang.Object... args) A convenience method to write a formatted string to this output stream using the specified format string and arguments.
java.io.PrintStream	printf(java.lang.String format, java.lang.Object... args) A convenience method to write a formatted string to this output stream using the specified format string and arguments.
void	println() Terminate the current line by writing the line separator string.
void	println(boolean x) Print a boolean 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 and then terminate the line.
void	println(float x) Print a float and then terminate the line.
void	println(int x) Print an integer and then terminate the line.
void	println(long x) Print a long and then terminate the line.
void	println(java.lang.Object x) Print an object and then terminate the line.
void	println(java.lang.String x) Print a string and then terminate the line.
void	write(byte[] buf, int off, int len) Write len bytes from the specified byte array starting at offset off to this stream.
void	write(int b) Write the specified byte to this stream.

Methods inherited from class java.io.PrintStream

clearError, setError

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LogPrintStream

public LogPrintStream(java.util.logging.Logger logger,
              java.util.logging.Level level)

Constructor.

The given stream is used to feed the underlying PrintStream (in fact no single byte will be written to it). All output methods are using the given logger instance.

This constructor will lead the stream not to produce any id prefixes for the log lines.

Parameters:

logger - Logging instance

level - Log level

Since:

1.5

LogPrintStream

public LogPrintStream(java.util.logging.Logger logger,
              java.util.logging.Level level,
              java.lang.String id)

Constructor.

The given stream is used to feed the underlying PrintStream (in fact no single byte will be written to it). All output methods are using the given logger instance. The optional id is used as prefix for the logging content. For instance id="out" leads to the following result: "2006-06-26 20:50:05.875 INFO (out) Some message". Normally this class is used to substitute System.out or System.err, so the id can be used to mark this replacement and see what's coming over the stream.

Notice that carriage return and linefeed characters are filtered to have nice log lines.

Parameters:

logger - Logging instance

level - Log level

id - Prefix for log lines, omitted by passing either null or empty string

Since:

1.5

Method Detail

append

public java.io.PrintStream append(char c)

Appends the specified character to this output stream.

Overwrites the original method implemented by SUN.

Specified by:

append in interface java.lang.Appendable

Overrides:

append in class java.io.PrintStream

Parameters:

c - The 16-bit character to append

Returns:

This output stream

Since:

1.5

append

public java.io.PrintStream append(java.lang.CharSequence csq)

Appends the specified character sequence to this output stream.

Overwrites the original method implemented by SUN.

Specified by:

append in interface java.lang.Appendable

Overrides:

append in class java.io.PrintStream

Parameters:

csq - The character sequence to append. If csq is null, then the four characters "null" are appended to this output stream.

Returns:

This character stream

Since:

1.5

append

public java.io.PrintStream append(java.lang.CharSequence csq,
                         int start,
                         int end)

Appends a subsequence of the specified character sequence to this output stream.

Overwrites the original method implemented by SUN.

Specified by:

append in interface java.lang.Appendable

Overrides:

append in class java.io.PrintStream

Parameters:

csq - The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null".

start - The index of the first character in the subsequence

end - The index of the character following the last character in the subsequence

Returns:

This character stream

Throws:

java.lang.IndexOutOfBoundsException - If start or end are negative, start is greater than end, or end is greater than csq.length().

Since:

1.5

checkError

public boolean checkError()

Flush the stream and check its error state.

Overwrites the original method implemented by SUN.

Overrides:

checkError in class java.io.PrintStream

Returns:

True if and only if this stream has encountered an IOException other than InterruptedIOException, or the setError method has been invoked

Since:

1.5

close

public void close()

Close the stream.

Overwrites the original method implemented by SUN.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.PrintStream

Since:

1.5

flush

public void flush()

Flush the stream.

Overwrites the original method implemented by SUN.

Specified by:

flush in interface java.io.Flushable

Overrides:

flush in class java.io.PrintStream

Since:

1.5

format

public java.io.PrintStream format(java.util.Locale l,
                         java.lang.String format,
                         java.lang.Object... args)

Writes a formatted string to this output stream using the specified format string and arguments.

Overwrites the original method implemented by SUN.

Overrides:

format in class java.io.PrintStream

Parameters:

l - The locale to apply during formatting. If l is null then no localization is applied.

format - A format string as described in Format string syntax

args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by the Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion.

Returns:

This output stream

Throws:

java.util.IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification.

java.lang.NullPointerException - If the format is null

Since:

1.5

format

public java.io.PrintStream format(java.lang.String format,
                         java.lang.Object... args)

Writes a formatted string to this output stream using the specified format string and arguments.

Overwrites the original method implemented by SUN.

Overrides:

format in class java.io.PrintStream

Parameters:

format - A format string as described in Format string syntax

args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by the Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion.

Returns:

This output stream

Throws:

java.util.IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification.

java.lang.NullPointerException - If the format is null

Since:

1.5

print

public void print(boolean b)

Print a boolean value.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

b - The boolean to be printed

Since:

1.5

print

public void print(char c)

Print a character.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

c - The char to be printed

Since:

1.5

print

public void print(char[] s)

Print an array of characters.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

s - The array of chars to be printed

Throws:

java.lang.NullPointerException - If s is null

Since:

1.5

print

public void print(double d)

Print a double-precision floating-point number.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

d - The double to be printed

Since:

1.5

print

public void print(float f)

Print a floating-point number.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

f - The float to be printed

Since:

1.5

print

public void print(int i)

Print an integer.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

i - The int to be printed

Since:

1.5

print

public void print(long l)

Print a long integer.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

l - The long to be printed

Since:

1.5

print

public void print(java.lang.Object obj)

Print an object.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

obj - The object to be printed

Since:

1.5

print

public void print(java.lang.String s)

Print a string.

Overwrites the original method implemented by SUN.

Overrides:

print in class java.io.PrintStream

Parameters:

s - The string to be printed

Since:

1.5

printf

public java.io.PrintStream printf(java.util.Locale l,
                         java.lang.String format,
                         java.lang.Object... args)

A convenience method to write a formatted string to this output stream using the specified format string and arguments.

Overwrites the original method implemented by SUN.

Overrides:

printf in class java.io.PrintStream

Parameters:

l - The locale to apply during formatting. If l is null then no localization is applied.

format - A format string as described in Format string syntax

args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by the Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion.

Returns:

This output stream

Throws:

java.util.IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification.

java.lang.NullPointerException - If the format is null

Since:

1.5

printf

public java.io.PrintStream printf(java.lang.String format,
                         java.lang.Object... args)

A convenience method to write a formatted string to this output stream using the specified format string and arguments.

Overwrites the original method implemented by SUN.

Overrides:

printf in class java.io.PrintStream

Parameters:

format - A format string as described in Format string syntax

args - Arguments referenced by the format specifiers in the format string. If there are more arguments than format specifiers, the extra arguments are ignored. The number of arguments is variable and may be zero. The maximum number of arguments is limited by the maximum dimension of a Java array as defined by the Java Virtual Machine Specification. The behaviour on a null argument depends on the conversion.

Returns:

This output stream

Throws:

java.util.IllegalFormatException - If a format string contains an illegal syntax, a format specifier that is incompatible with the given arguments, insufficient arguments given the format string, or other illegal conditions. For specification of all possible formatting errors, see the Details section of the formatter class specification.

java.lang.NullPointerException - If the format is null

Since:

1.5

println

public void println()

Terminate the current line by writing the line separator string.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Since:

1.5

println

public void println(boolean x)

Print a boolean and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The boolean to be printed

Since:

1.5

println

public void println(char x)

Print a character and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The char to be printed

Since:

1.5

println

public void println(char[] x)

Print an array of characters and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The array of chars to be printed

Throws:

java.lang.NullPointerException - If s is null

Since:

1.5

println

public void println(double x)

Print a double and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The double to be printed

Since:

1.5

println

public void println(float x)

Print a float and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The float to be printed

Since:

1.5

println

public void println(int x)

Print an integer and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The int to be printed

Since:

1.5

println

public void println(long x)

Print a long and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The long to be printed

Since:

1.5

println

public void println(java.lang.Object x)

Print an object and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The object to be printed

Since:

1.5

println

public void println(java.lang.String x)

Print a string and then terminate the line.

Overwrites the original method implemented by SUN.

Overrides:

println in class java.io.PrintStream

Parameters:

x - The string to be printed

Since:

1.5

write

public void write(byte[] buf,
         int off,
         int len)

Write len bytes from the specified byte array starting at offset off to this stream.

Overwrites the original method implemented by SUN.

Overrides:

write in class java.io.PrintStream

Parameters:

buf - A byte array

off - Offset from which to start taking bytes

len - Number of bytes to write

Since:

1.5

write

public void write(int b)

Write the specified byte to this stream.

Overwrites the original method implemented by SUN.

Overrides:

write in class java.io.PrintStream

Parameters:

b - The byte to be written

Since:

1.5