com.android.builder.dexing

Class DxDexArchiveMerger

java.lang.Object

com.android.builder.dexing.DxDexArchiveMerger

All Implemented Interfaces:

DexArchiveMerger

public final class DxDexArchiveMerger
extends java.lang.Object
implements DexArchiveMerger

Merges DEX files found in DexArchives, and produces the final DEX file(s). Inputs can come from one or more dex archives. In order to process the dex archives, one should invoke mergeDexArchives(Iterator, Path, Path, DexingType) method.

In order to merge individual DEX files, we are using DexMergingStrategy to determine how many input DEX files can fit into a single output DEX.

Merging is actually executed by invoking the DexMerger, which is part of dx.

Constructor Summary

Constructors

Constructor and Description
DxDexArchiveMerger(com.android.dx.command.dexer.DxContext dxContext, java.util.concurrent.ForkJoinPool forkJoinPool, boolean isDebuggable) Creates an instance of merger.

Method Summary

Modifier and Type	Method and Description
void	mergeDexArchives(java.util.Iterator<java.nio.file.Path> inputs, java.nio.file.Path outputDir, java.nio.file.Path mainDexClasses, com.android.builder.dexing.DexingType dexingType) Triggers the actual merging by processing all DEX files from dex archives, and outputting the DEX file(s) in the specified directory.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.android.builder.dexing.DexArchiveMerger

createD8DexMerger, createDxDexMerger

Constructor Detail

DxDexArchiveMerger

public DxDexArchiveMerger(@NonNull
                          com.android.dx.command.dexer.DxContext dxContext,
                          @NonNull
                          java.util.concurrent.ForkJoinPool forkJoinPool,
                          boolean isDebuggable)

Creates an instance of merger. The executor that is specified in parameters will be used to schedule tasks. Important to notice is that merging, triggered by invoking mergeDexArchives(Iterator, Path, Path, DexingType) method, might return before final DEX file(s) are merged and written out. Therefore, the invoker will have to block on the executor, in order to be sure the merging is finished.

Parameters:

dxContext - dx context necessary for the merging process

forkJoinPool - executor used to schedule tasks in the merging process

isDebuggable - if we are merging debuggable variant

Method Detail

mergeDexArchives

public void mergeDexArchives(@NonNull
                             java.util.Iterator<java.nio.file.Path> inputs,
                             @NonNull
                             java.nio.file.Path outputDir,
                             @Nullable
                             java.nio.file.Path mainDexClasses,
                             @NonNull
                             com.android.builder.dexing.DexingType dexingType)
                      throws DexArchiveMergerException

Triggers the actual merging by processing all DEX files from dex archives, and outputting the DEX file(s) in the specified directory. DEX files will have names classes.dex, classes2.dex etc. It is the responsibility of the invoker to make sure the output directory is empty and writable. Merging might return before the DEX file(s) are merged and written out, so invoker should check if all tasks scheduled using the instance's thread pool are completed.

In case of mono-dex, it is expected that all DEX files will fit into a single output DEX file. If this is not possible, exception will be thrown.

When merging native multidex, multiple DEX files might be created.

In case of legacy multidex, list of classes in the main dex should be specified as well. When using legacy multidex mode in debug mode, only classes explicitly specified in this list will be in the main dex file. This is equivalent of invoking dx with --minimal-main-dex option. When in release mode, remaining space in the main dex will be used to add additional classes.

Specified by:

mergeDexArchives in interface DexArchiveMerger

Parameters:

inputs - paths to the dex archives that should be merged

outputDir - directory where merged dex file(s) will be written, must exist

mainDexClasses - file containing list of classes to be merged in the main dex file. It is null for native and mono dex, and must be non-null for legacy dex.

dexingType - specifies how to merge dex files

Throws:

DexArchiveMergerException