package com.esotericsoftware.minlog;

import java.io.PrintWriter;

import java.io.StringWriter;

/** A low overhead, lightweight logging system.

* @author Nathan Sweet <[email protected]> */

public class Log {

/** No logging at all. */

static public final int LEVEL_NONE = 6;

/** Critical errors. The application may no longer work correctly. */

static public final int LEVEL_ERROR = 5;

/** Important warnings. The application will continue to work correctly. */

static public final int LEVEL_WARN = 4;

/** Informative messages. Typically used for deployment. */

static public final int LEVEL_INFO = 3;

/** Debug messages. This level is useful during development. */

static public final int LEVEL_DEBUG = 2;

/** Trace messages. A lot of information is logged, so this level is usually only needed when debugging a problem. */

static public final int LEVEL_TRACE = 1;

/** The level of messages that will be logged. Compiling this and the booleans below as "final" will cause the compiler to

* remove all "if (Log.info) ..." type statements below the set level. */

static private int level = LEVEL_INFO;

/** True when the ERROR level will be logged. */

static public boolean ERROR = level <= LEVEL_ERROR;

/** True when the WARN level will be logged. */

static public boolean WARN = level <= LEVEL_WARN;

/** True when the INFO level will be logged. */

static public boolean INFO = level <= LEVEL_INFO;

/** True when the DEBUG level will be logged. */

static public boolean DEBUG = level <= LEVEL_DEBUG;

/** True when the TRACE level will be logged. */

static public boolean TRACE = level <= LEVEL_TRACE;

static public int getLevel () {

return level;

}

/** Sets the level to log. If a version of this class is being used that has a final log level, this has no affect. */

static public void set (int level) {

// Comment out method contents when compiling fixed level JARs.

Log.level = level;

ERROR = level <= LEVEL_ERROR;

WARN = level <= LEVEL_WARN;

INFO = level <= LEVEL_INFO;

DEBUG = level <= LEVEL_DEBUG;

TRACE = level <= LEVEL_TRACE;

}

static public void NONE () {

set(LEVEL_NONE);

}

static public void ERROR () {

set(LEVEL_ERROR);

}

static public void WARN () {

set(LEVEL_WARN);

}

static public void INFO () {

set(LEVEL_INFO);

}

static public void DEBUG () {

set(LEVEL_DEBUG);

}

static public void TRACE () {

set(LEVEL_TRACE);

}

/** Sets the logger that will write the log messages. */

static public void setLogger (Logger logger) {

Log.logger = logger;

}

static private Logger logger = new Logger();

static public void error (String message, Throwable ex) {

if (ERROR) logger.log(LEVEL_ERROR, null, message, ex);

}

static public void error (String category, String message, Throwable ex) {

if (ERROR) logger.log(LEVEL_ERROR, category, message, ex);

}

static public void error (String message) {

if (ERROR) logger.log(LEVEL_ERROR, null, message, null);

}

static public void error (String category, String message) {

if (ERROR) logger.log(LEVEL_ERROR, category, message, null);

}

static public void warn (String message, Throwable ex) {

if (WARN) logger.log(LEVEL_WARN, null, message, ex);

}

static public void warn (String category, String message, Throwable ex) {

if (WARN) logger.log(LEVEL_WARN, category, message, ex);

}

static public void warn (String message) {

if (WARN) logger.log(LEVEL_WARN, null, message, null);

}

static public void warn (String category, String message) {

if (WARN) logger.log(LEVEL_WARN, category, message, null);

}

static public void info (String message, Throwable ex) {

if (INFO) logger.log(LEVEL_INFO, null, message, ex);

}

static public void info (String category, String message, Throwable ex) {

if (INFO) logger.log(LEVEL_INFO, category, message, ex);

}

static public void info (String message) {

if (INFO) logger.log(LEVEL_INFO, null, message, null);

}

static public void info (String category, String message) {

if (INFO) logger.log(LEVEL_INFO, category, message, null);

}

static public void debug (String message, Throwable ex) {

if (DEBUG) logger.log(LEVEL_DEBUG, null, message, ex);

}

static public void debug (String category, String message, Throwable ex) {

if (DEBUG) logger.log(LEVEL_DEBUG, category, message, ex);

}

static public void debug (String message) {

if (DEBUG) logger.log(LEVEL_DEBUG, null, message, null);

}

static public void debug (String category, String message) {

if (DEBUG) logger.log(LEVEL_DEBUG, category, message, null);

}

static public void trace (String message, Throwable ex) {

if (TRACE) logger.log(LEVEL_TRACE, null, message, ex);

}

static public void trace (String category, String message, Throwable ex) {

if (TRACE) logger.log(LEVEL_TRACE, category, message, ex);

}

static public void trace (String message) {

if (TRACE) logger.log(LEVEL_TRACE, null, message, null);

}

static public void trace (String category, String message) {

if (TRACE) logger.log(LEVEL_TRACE, category, message, null);

}

private Log () {

}

/** Performs the actual logging. Default implementation logs to System.out. Extended and use {@link Log#logger} set to handle

* logging differently. */

static public class Logger {

private final long firstLogTime = System.currentTimeMillis();

public void log (int level, String category, String message, Throwable ex) {

StringBuilder builder = new StringBuilder(256);

long time = System.currentTimeMillis() - firstLogTime;

long minutes = time / (1000 * 60);

long seconds = time / (1000) % 60;

if (minutes <= 9) builder.append('0');

builder.append(minutes);

builder.append(':');

if (seconds <= 9) builder.append('0');

builder.append(seconds);

switch (level) {

case LEVEL_ERROR:

builder.append(" ERROR: ");

break;

case LEVEL_WARN:

builder.append(" WARN: ");

break;

case LEVEL_INFO:

builder.append(" INFO: ");

break;

case LEVEL_DEBUG:

builder.append(" DEBUG: ");

break;

case LEVEL_TRACE:

builder.append(" TRACE: ");

break;

}

if (category != null) {

builder.append('[');

builder.append(category);

builder.append("] ");

}

builder.append(message);

if (ex != null) {

StringWriter writer = new StringWriter(256);

ex.printStackTrace(new PrintWriter(writer));

builder.append('\n');

builder.append(writer.toString().trim());

}

print(builder.toString());

}

/** Prints the message to System.out. Called by the default implementation of {@link #log(int, String, String, Throwable)}. */

protected void print (String message) {

System.out.println(message);

}

}

}