Mar 2, 2016
Feb 23, 2022 (Retired)
Source code


A simple android gradle plugin to use the patterns of package to smart split the specified classes to multi dex. Also supports android gradle plugin 2.2.0 multidex. Solve android studio enable the native multidex feature, but there will be too many classes in main dex. (See Features 7)

  • Notes: Because instant-run of 2.0.0 above is incompatible with multidex, DexKnife is auto disabled when instant-run mode. It will auto enable when disabled instant-run or in packaging release.(minsdk < 21)


Update Log

1.6.1: Compatible with android gradle plugin 2.3.0, auto disable when build with ART-Runtime (See Features 8).
1.6.0: Modify: When only -keep is configured, only keep the specified classes.
1.5.9: Compatible with some ancient version of gradle and android gradle plugin.
1.5.8: Compatible with gradle 3.2, fixed use of only support-split and support-keep resulting in an extra large number of classes.
1.5.7: fixed support-split and support-keep are not work. (修复support-split/support-keep无效的bug)
1.5.6: Experimentally compatible with java 1.7, fix nothing is selected when only -keep. (实验性的支持java 1.7,修复但只有keep选项时没有类被选中)
1.5.5: support individual filter for suggest maindexlist. (单独的maindexlist过滤设置)
1.5.5.alpha: Experimentally compatible with android gradle plugin on 2.2.0. (实验性的支持 2.2.0 plugin)
1.5.4: auto disabled when instant run mode.(instant run 模式时自动禁用DexKnife)
1.5.3: add some track logs and skip DexKnife when jarMerging is null.(增加跟踪日志,并在jarMerging为null跳过处理)
1.5.2: fixed the include and exclude path, and supports filtering single class.(修复include和exclude, 并支持过滤单个类)
1.5.1.exp: Experimentally compatible with android gradle plugin on 2.1.0 (实验性的支持 2.1.0 plugin)
1.5.1: fixed the proguard mode


  1. DexKnife just converts the wildcards of class path to maindexlist.txt, does not participate in other compilation process. It is not automatic tools, you need to have a understanding of the maindexlist features.

  2. If the class can not be found (ie class no def / found) at runtime, enable DexKnife's log function, debug the config of dexKnife and check the config ProGuard. Verify the generated maindexlist.txt match your config. Do not split the classes in the Application class into second dex. (Even if you manually configure the maindexlist will be such a problem.)

  3. DexKnife can only explicitly specify the classes of main dex, can not specify the classes of after the second dex (limitation of dex's param maindexlist). If you need to completely configure the main dex manually, use: -donot-use-suggest
    -split **
    -keep** # keep multidex lib
    -keep # wildcards of other keeping classes, and the count of idx don't overflow 65535

  4. DexKnife does not have dependency detection and requires you to configure it manually because DexKnife does not know your project requirements.

  5. DexKnife uses the original classpath as the configuration, not the obfuscated classpath.

  6. the count of ID that generated by -keep can not overflow 65535, otherwise there will be error of too many class.

  7. If you use the android gradle plugin's native multidex, but the declaration in the manifest is too much, resulting in the number of methods and variables are still overflow, or can not be packaged. You can simply use -suggest-split to move some of the classes in the suggest list out of the main dex.

  8. minsdk < 21. If minsdk >= 21, the android gradle plugin will build with ART-Runtime, MainDexList isn't necessary, DexKnife is auto disable. In debug mode with Android Gradle plugin >= 2.3.0, minsdk is associated with min(Target running device, TargetSdk). Make sure your MinSdkVersion < 21, DexKnife will auto enable in release mode if conditions are compatible.


1.In your project's build.gradle, buildscript.

    buildscript {
        dependencies {
            classpath ''  // or other
            classpath 'com.ceabie.dextools:gradle-dexknife-plugin:1.6.1'

please make sure gradle version is compatible with the android gradle plugin, otherwise it can causes some sync error, such as:
Gradle sync failed: Unable to load class ''.

2.Create a 'dexknife.txt' in your App's module, and config the patterns of classes path that wants to put into sencond dex.
(The rest of any classes that is not marked split will be in miandexlist)

    Patterns may include:

    '*' to match any number of characters
    '?' to match any single character
    '**' to match any number of directories or files
    Either '.' or '/' may be used in a pattern to separate directories.
    Patterns ending with '.' or '/' will have '**' automatically appended.

Also see:

Other config key:

'#' is the comment, config is disabled when '#' adds on line start.

# Global filter, don't apply with suggest maindexlist if -filter-suggest is DISABLE.
# this path will to be split to second dex.**

# if you want to keep some classes in main dex, use '-keep'.

# you can keep single class in main dex, end with '.class', use '-keep'.

# do not use suggest of the maindexlist that android gradle plugin generate.

# the global filter apply with maindexlist, if -donot-use-suggest is DISABLE.

# Notes: Split dex until the dex's id > 65536. --minimal-main-dex is default.
-auto-maindex  # default is not used.

# dex additional parameters, such as --set-max-idx-number=50000
# if number is too small, it will cause DexException: Too many classes in --main-dex-list, main dex capacity exceeded
-dex-param --set-max-idx-number=50000

# log the main dex classes.

# log the filter classes of suggest maindexlist, if -filter-suggest is enabled..

#the filter log。Recommend;Global;true;false

# if you only filter the suggest maindexlist, use -suggest-split and -suggest-keep.
# Global filter will merge into them if -filter-suggest is ENABLE at same time.
-suggest-split **.MainActivity2.class

Note: if you want to filter the inner classes, use $*, such as: SomeClass$*.class

3.add to your app's build.gradle, add this line:

apply plugin: 'com.ceabie.dexnkife'

and then, set your app

multiDexEnabled true
  • Notes: You want to set 'multiDexEnabled true' in 'defaultConfig' or 'buildTypes', otherwise ineffective. your app


一个简单的将指定使用通配符包名分包到第二个dex中gradle插件。(使用疑问查看 特性) 同时支持 android gradle plugin 2.2.0 multidex. 可以解决 android studio 使用 multidex,但还会出现dex类太多的问题。(参见 特性 7)

  • 注意:由于高于 2.0.0 的 instant-run 和 ART-Runtime 特性与 multidex不兼容,DexKnife会暂时禁用。当instant-run被禁用或者release打包时会自动启用。(minsdk < 21)


1.6.1: 兼容 Android gradle plugin 2.3.0,在 ART-Runtime编译模式下自动禁用,增加相关提示。(参见 特性 8)
1.6.0: 修改:当只有keep时,只保留keep指定的类
1.5.9: 兼容一些古老的 gradle 和 android gradle plugin版本
1.5.8: 兼容gradle 3.2,修复当只使用support-split/support-keep时出现大量的额外类
1.5.7: 修复support-split/support-keep无效的bug
1.5.6: 实验性的支持java 1.7,修复但只有keep选项时没有类被选中
1.5.5: 增加单独的maindexlist过滤设置
1.5.5.alpha: 实验性的支持 2.2.0 plugin
1.5.4: instant run 模式时自动禁用DexKnife
1.5.3: 增加跟踪日志,并在jarMerging为null时跳过处理
1.5.2: 修复include和exclude, 并支持过滤单个类
1.5.1.exp: 实验性的支持 2.1.0 plugin
1.5.1: 修复 proguard mode


  1. DexKnife只负责由配置的 类路径通配符 -> maindexlist 文件的转换,生成maindexlist.txt,不参与其他的处理和编译过程。非全自动工具,需要对maindexlist特性有较深的了解。

  2. 如果出现运行时类找不到(i.e. class no def/found),请打开DexKnife的log功能,比对调试下DexKnife或ProGuard配置,并检查生成的maindexlist是否匹配你的配置。不要将在Application中使用到的类,分到第二个dex中。(即使不使用DexKnife,手动配置maindexlist也会出现这样的问题)

  3. DexKnife只能明确指定第一个dex中的类,不能明确指定第二个dex以后的类(dex的maindexlist限制)。如果需要完全手动配置第一个dex,使用
    -split **
    -keep** # 保证 multidex 或者你自己开发的multidex
    -keep # 配置你的keep类的通配符,但数量不能超界

  4. DexKnife不带有依赖检测,需要你手动配置,因为DexKnife并不知道你的项目需求。

  5. DexKnife使用原始类路径作为配置,不要使用混淆后的类路径。

  6. -keep 的类所产生的ID数量不能超过65535,否则会出现 Too many classes 的错误。

  7. 如果使用android gradle plugin原生的multidex,但由于manifest中声明的类过多,导致所包含的方法和变量的数量还是超出上限,出现dex的类还是太多,还是无法打包。可以仅使用-suggest-split将推荐列表中的一些类移出第一个dex,剩下打包工具会自行分配。

  8. minsdk < 21。如果 minsdk >= 21,官方将换用ART编译方式,已经不需要MainDexList,DexKnife会自动禁用。Android Gradle plugin >= 2.3.0时,在debug状态下,minsdk会暂时设为 min(目标运行设备, TargetSdk),只要 minsdk < 21,Release模式时会自动启用。


1.在你的工程的 build.gradle 中 buildscript:

    buildscript {
        dependencies {
            classpath ''  // or other
            classpath 'com.ceabie.dextools:gradle-dexknife-plugin:1.6.1'

注意,请确保使用的gradle版本和android gradle plugin兼容,否则会出现同步错误,例如:
Gradle sync failed: Unable to load class ''.

2.在App模块下创建 dexknife.txt,并填写要放到第二个dex中的包名路径的通配符.(注意,其余任何未被注明split的类都会在miandexlist)

    Patterns may include:

    '*' to match any number of characters
    '?' to match any single character
    '**' to match any number of directories or files
    Either '.' or '/' may be used in a pattern to separate directories.
    Patterns ending with '.' or '/' will have '**' automatically appended.



使用 # 进行注释, 当行起始加上 #, 这行配置被禁用.

# 全局过滤, 如果没设置 -filter-suggest 并不会应用到 建议的maindexlist.
# 如果你想要某个已被排除的包路径在maindex中,则使用 -keep 选项,即使他已经在分包的路径中.
# 注意,没有split只用keep时,miandexlist将仅包含keep指定的类。

# 这条配置可以指定这个包下类在第二dex中.(注意,未指定的类会在被认为在maindexlist中)**

# 使用.class后缀,代表单个类.

# 不包含Android gradle 插件自动生成的miandex列表.

# 将 全局过滤配置应用到 建议的maindexlist中, 但 -donot-use-suggest 要关闭.

# 不进行dex分包, 直到 dex 的id数量超过 65536.

# dex 扩展参数, 例如 --set-max-idx-number=50000
# 如果出现 DexException: Too many classes in --main-dex-list, main dex capacity exceeded,则需要调大数值
-dex-param --set-max-idx-number=50000

# 显示miandex的日志.


# 如果你只想过滤 建议的maindexlist, 使用 -suggest-split 和 -suggest-keep.
# 如果同时启用 -filter-suggest, 全局过滤会合并到它们中.
-suggest-split **.MainActivity2.class


  1. 过滤的类路径使用非混淆的。
  2. 使用全局split(或不加,也当做排除的),仅仅只有指定了split的类才会被移出maindex,未标注的剩余类都会保留在maindex中。如果只使用keep,那只有被keep的类会在maindexlist。配置不当会,会出现未指定过的类。
  3. suggest-split与suggest-keep规则如同 第2条。
  4. 如果使用了全局过滤,又使用了suggest-xxx,那么只要其中一个结果成立,那么这个类都会maindexlist中。建议仅使用suggest-split对ADT推荐的列表进行再过滤。
  5. 如果你要过滤内部类, 使用$*,例如: SomeClass$*.class。

3.在你的App模块的build.gradle 增加:

apply plugin: 'com.ceabie.dexnkife'


multiDexEnabled true
  • 注意:要在 defaultConfig 或者 buildTypes中打开 multiDexEnabled true,否则不起作用。



在Terminal中运行 gradleDebug。具体参见:


Copyright (C) 2017 ceabie (

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
See the License for the specific language governing permissions and
limitations under the License.