Android logger, simple and pretty, powerful and flexible, all you need is here (updating)
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Simple and pretty, powerful and flexible logger for android and java, can concurrently print the log to multiple target like Logcat, Console and File, or even Server(or anywhere) if you like.

What XLog can do:

  • Global config(tag, formatters...) or log-based config
  • Support printing any object and customizable object formatter
  • Support printing array
  • Support printing long log (No 4K limitation)
  • XML and JSON formatted
  • Thread information (Thread name etc. Can be customized)
  • Stack trace information (Configurable call stack depth, with file name, method name, line number)
  • Support log interceptors
  • Save logs in file (Configurable file naming and backup strategy)
  • Good looking in Android Studio
  • Easy to use, powerful in customization

The differences to other logger libraries:

  • Pretty source code and document
  • So flexible that you can easily customize or enhance it
  • Lightweight, no other dependencies


compile 'com.elvishew:xlog:1.6.1'


  • Log with thread information, stack trace information and border
  • Formatted network API request
  • Formatted network API response
  • Log files




Simple way


Or if you want to disable the log in release version

XLog.init(BuildConfig.DEBUG ? LogLevel.ALL : LogLevel.NONE);

Advance way

LogConfiguration config = new LogConfiguration.Builder()
    .logLevel(BuildConfig.DEBUG ? LogLevel.ALL             // Specify log level, logs below this level won't be printed, default: LogLevel.ALL
        : LogLevel.NONE)
    .tag("MY_TAG")                                         // Specify TAG, default: "X-LOG"
    .t()                                                   // Enable thread info, disabled by default
    .st(2)                                                 // Enable stack trace info with depth 2, disabled by default
    .b()                                                   // Enable border, disabled by default
    .jsonFormatter(new MyJsonFormatter())                  // Default: DefaultJsonFormatter
    .xmlFormatter(new MyXmlFormatter())                    // Default: DefaultXmlFormatter
    .throwableFormatter(new MyThrowableFormatter())        // Default: DefaultThrowableFormatter
    .threadFormatter(new MyThreadFormatter())              // Default: DefaultThreadFormatter
    .stackTraceFormatter(new MyStackTraceFormatter())      // Default: DefaultStackTraceFormatter
    .borderFormatter(new MyBoardFormatter())               // Default: DefaultBorderFormatter
    .addObjectFormatter(AnyClass.class,                    // Add formatter for specific class of object
        new AnyClassObjectFormatter())                     // Use Object.toString() by default
    .addInterceptor(new BlacklistTagsFilterInterceptor(    // Add blacklist tags filter
        "blacklist1", "blacklist2", "blacklist3"))
    .addInterceptor(new MyInterceptor())                   // Add a log interceptor

Printer androidPrinter = new AndroidPrinter();             // Printer that print the log using android.util.Log
Printer consolePrinter = new ConsolePrinter();             // Printer that print the log to console using System.out
Printer filePrinter = new FilePrinter                      // Printer that print the log to the file system
    .Builder("/sdcard/xlog/")                              // Specify the path to save log file
    .fileNameGenerator(new DateFileNameGenerator())        // Default: ChangelessFileNameGenerator("log")
    .backupStrategy(new NeverBackupStrategy())             // Default: FileSizeBackupStrategy(1024 * 1024)
    .cleanStrategy(new FileLastModifiedCleanStrategy(MAX_TIME))     // Default: NeverCleanStrategy()
    .flattener(new MyFlattener())                          // Default: DefaultFlattener

XLog.init(                                                 // Initialize XLog
    config,                                                // Specify the log configuration, if not specified, will use new LogConfiguration.Builder().build()
    androidPrinter,                                        // Specify printers, if no printer is specified, AndroidPrinter(for Android)/ConsolePrinter(for java) will be used.

For android, a best place to do the initialization is Application.onCreate().

Global Usage

XLog.d("Simple message")
XLog.d("My name is %s", "Elvis");
XLog.d("An exception caught", exception);
... // Other global usage

Partial usage

Build a logger.

Logger partial = XLog.tag("PARTIAL-LOG")
    ... // Other configs

And use it partially, the logging methods is completely the same as that ones in XLog.

partial.d("Simple message 1");
partial.d("Simple message 2");
... // Other partial usage

Log-based usage

Setup log-based configs and log immediately, the logging methods is completely the same as that ones in XLog.

XLog.t()    // Enable thread into
    .st(3)  // Enable stack trace info with depth 3
    .b()    // Enable border
    ...     // Other configs
    .d("Simple message 1");

    .st(0)  // Enable stack trace info without limitation
    ...     // Other configs
    .d("Simple message 2");

XLog.nt()   // Disable thread info
    .nst()  // Disable stack trace info
    .d("Simple message 3");

XLog.b().d("Simple message 4");


Let's imagine there are a JSON string and a XML string

String jsonString = "{\"name\": \"Elvis\", \"age\": 18}";
String xmlString = "<team><member name="Elvis"/><member name="Leon"/></team>";

Android Log

Log.d(TAG, "Message");
Log.d(TAG, String.format("Message with argument: age=%s", 18));
Log.d(TAG, jsonString);
Log.d(TAG, xmlString);
Log.d(TAG, "Message with stack trace info", new Throwable());


XLog.d("Message with argument: age=%s", 18);
XLog.xml(xmlString);"Message with stack trace info");

XLog with border

XLog.init(LogLevel.ALL, new LogConfiguration.Builder().b().build());
XLog.d("Message with argument: age=%s", 18);
XLog.xml(xmlString);"Message with stack trace info");

Similar libraries


In order to be compatible with Android Log, all the methods of Android Log are supported here.
See the Log class defined in XLog.

Log.v(String, String);
Log.v(String, String, Throwable);
Log.d(String, String);
Log.d(String, String, Throwable);
Log.i(String, String);
Log.i(String, String, Throwable);
Log.w(String, String);
Log.w(String, String, Throwable);, String);, String, Throwable);
Log.e(String, String);
Log.e(String, String, Throwable);
Log.println(int, String, String);
Log.isLoggable(String, int);


If you have a big project using the Android Log, and it is a hard work to change all usage of Android Log to XLog, then you can use the compatible API, simply replace all 'android.util.Log' to 'com.elvishew.xlog.XLog.Log'.
(For a better performance, you should think about not using the compatible API.)


grep -rl "android.util.Log" <your-source-directory> | xargs sed -i "s/android.util.Log/com.elvishew.xlog.XLog.Log/g"


grep -rl "android.util.Log" <your-source-directory> | xargs sed -i "" "s/android.util.Log/com.elvishew.xlog.XLog.Log/g"

Android Studio

In 'Project' pane, switch to the 'Project Files' tab, then right-click on the your source directory.
In the menu, click the 'Replace in Path...' option.
In the dialog, fill the 'Text to find' with 'android.util.Log', and 'Replace with' with 'com.elvishew.xlog.XLog.Log', and click 'Find'.


  • Print any object: XLog.d(Object) (since 1.1.0)
  • Support log interceptors(similar to okhttp's Interceptor, here we use it for intercepting log) (since 1.3.0)
  • Add tags filter (blacklist filter and whitelist filter) (since 1.3.0)
  • Add PatternFlattener(mostly used when logging to file), e.g: use pattern "{d yyyy-MM-dd hh:mm:ss.SSS} {l}/{t}: {m}" and the flattened log would be "2016-10-30 13:00:00,000 W/my_tag: Simple message" (since 1.3.0)
  • Log to file asynchronously (since 1.3.0)
  • Logger-based log level control rather than current global one (since 1.3.0)
  • Add builtin formatter for Bundle and Intent object (since 1.4.0)
  • Export log files to a .zip (since 1.4.0)


Latest release: 1.6.1 Change log


If you meet any problem when using XLog, or have any suggestion, please feel free to create an issue.


Thanks to Orhan Obut's logger, it give me many ideas of what a logger can do.

Thanks to Serge Zaitsev's log, it give me the thought of making XLog compatible with Android Log.


Copyright 2018 Elvis Hew

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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See the License for the specific language governing permissions and
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