[Android] Android Engineering provides services to third-party applications in the form of jar packages

Reference: http://www.cnblogs.com/0616--ataozhijia/p/4094952.html

Take API 19 as an example:

The overall size of the system provided by default is: 21.8 MB Android.jar

After manually deleting the resource file, the Android.jar size is: 2.6 MB

from which you can determine: The jar package is the one that can be placed in the resource file

So how are the resources in the jar package called??

In pure Java mode: see reference

On Android: reference: http://blog.csdn.net/liguangzhenghi/article/details/8858544

1, jar is included in other projects, the resulting APK file contains the resources in the jar (the directory structure is the same), this can be opened by the zip jar and apk view.

2. The resource in the jar should also be managed by the JVM, but because its actual ID is inconsistent with the ID generated in the original Jar project, the resource ID in the original JAR project cannot be used to access the actual resource. Access can only be done by GetClass (). getClassLoader (). getResourceAsStream ().

For component development using the JAR approach, you need to be aware of the following:

1. The jar package typically contains only code that does not contain resources.

2. If you want to include resources in the jar, the resource files should not be placed in the default res directory (because there may be conflicting names after importing other items), you should create a dedicated resource directory under the package directory, so that the pakcage does not conflict with the names of the imported resources. At the same time, the code in the jar cannot be accessed directly using the resource ID in the R class, and should be loaded by GetClass (). getClassLoader (). getResourceAsStream ().

3. String resources can be defined as constants in the way they are used.

[Android] Android Engineering provides services to third-party applications in the form of jar packages