com.android.builder.packaging

Class PackagingUtils

java.lang.Object

com.android.builder.packaging.PackagingUtils

public class PackagingUtils
extends java.lang.Object

Utility class for packaging.

Field Summary

Fields

Modifier and Type	Field and Description
static com.google.common.collect.ImmutableSet<java.lang.String>	DEFAULT_DONT_COMPRESS_EXTENSIONS Set of file formats which are already compressed, or don't compress well, same as the one used by aapt.
static com.google.common.collect.ImmutableList<java.lang.String>	SIGNING_EXTENSIONS List of file extensions that are used for jar signing.

Constructor Summary

Constructors

Constructor and Description
PackagingUtils()

Method Summary

Modifier and Type	Method and Description
static boolean	checkFileForApkPackaging(java.lang.String filePath, boolean allowClassFiles) Checks a file to make sure it should be packaged as standard resources.
static long	computeApplicationHash(java.io.File projectDir) Computes an "application hash", a reasonably unique identifier for an app.
static java.util.function.Predicate<java.lang.String>	getDefaultNoCompressPredicate()
static com.android.apkzlib.zfile.NativeLibrariesPackagingMode	getNativeLibrariesLibrariesPackagingMode(java.io.File manifest)
static java.util.function.Predicate<java.lang.String>	getNoCompressPredicate(com.android.builder.model.AaptOptions aaptOptions, java.io.File manifest)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_DONT_COMPRESS_EXTENSIONS

public static final com.google.common.collect.ImmutableSet<java.lang.String> DEFAULT_DONT_COMPRESS_EXTENSIONS

Set of file formats which are already compressed, or don't compress well, same as the one used by aapt.

SIGNING_EXTENSIONS

public static final com.google.common.collect.ImmutableList<java.lang.String> SIGNING_EXTENSIONS

List of file extensions that are used for jar signing.

Constructor Detail

PackagingUtils

public PackagingUtils()

Method Detail

checkFileForApkPackaging

public static boolean checkFileForApkPackaging(@NonNull
                                               java.lang.String filePath,
                                               boolean allowClassFiles)

Checks a file to make sure it should be packaged as standard resources.

Parameters:

filePath - OS-independent path of the file (including extension), relative to the archive

allowClassFiles - whether to allow java class files

Returns:

true if the file should be packaged as standard java resources

computeApplicationHash

public static long computeApplicationHash(@NonNull
                                          java.io.File projectDir)

Computes an "application hash", a reasonably unique identifier for an app.

This is currently used by Instant Run to prevent apps on a device from guessing the authentication token associated with an instant run developed app on the same device.

This method creates the "secret", the field in the AppInfo class which is used as a simple authentication token between the IDE and the app server.

This is not a cryptographically strong unique id; we could attempt to make a truly random number here, but we'd need to store that id somewhere such that subsequent builds will use the same secret, to avoid having the IDE and the app getting out of sync, and there isn't really a natural place for us to store the key to make it survive across a clean build. (One possibility is putting it into local.properties).

However, we have much simpler needs: we just need a key that can't be guessed from a hostile app on the developer's device, and it only has a few guesses (after providing the wrong secret to the server a few times, the server will shut down.) We can't rely on the package name alone, since the port number is known, and the package name is discoverable by the hostile app (by querying the contents of /data/data/*). Therefore we also include facts that the hostile app can't know, such as as the path on the developer's machine to the app project and the name of the developer's machine, etc. The goal is for this secret to be reasonably stable (e.g. the same from build to build) yet not something an app could guess if it only has a couple of tries.

getDefaultNoCompressPredicate

@NonNull
public static java.util.function.Predicate<java.lang.String> getDefaultNoCompressPredicate()

getNoCompressPredicate

@NonNull
public static java.util.function.Predicate<java.lang.String> getNoCompressPredicate(@NonNull
                                                                                             com.android.builder.model.AaptOptions aaptOptions,
                                                                                             @NonNull
                                                                                             java.io.File manifest)

getNativeLibrariesLibrariesPackagingMode

@NonNull
public static com.android.apkzlib.zfile.NativeLibrariesPackagingMode getNativeLibrariesLibrariesPackagingMode(@NonNull
                                                                                                                       java.io.File manifest)