Android：导入所需的系统jar包到Android studio

1. 修改对于的AIDL文件，根据编译信息获知所需的jar包。

　mmm /frameworks/base/ show commands > log.txt 2>&1

　　out/target/common/obj/JAVA_LIBRARIES/framework_intermediates/classes.jar   （frameworks.jar是dex格式，非原生态Java文件）

2.导入classes.jar到Android studio工程：

　　将系统jar包放到module的libs文件夹下，在Module下的build.gradle添加：

provided files('libs/classes.jar')  //在Android studio3.0 后，provided 被 compileOnly 替代

　　或界面如下操作：

　

3.添加依赖并修改优先级：

build.gradle：

dependencies {
    compileOnly files('libs/mframework.jar')
　　...
}

gradle.projectsEvaluated {
    tasks.withType(JavaCompile) {
        options.compilerArgs.add('-Xbootclasspath/p:app/libs/mframework.jar')
    }
}

preBuild { //将Android SDK优先级降到最低，实质是修改 Module下的.iml
    doLast {
        def imlFile = file(project.name + ".iml")
        println 'Change ' + project.name + '.iml order'
        try {
            def parsedXml = (new XmlParser()).parse(imlFile)
            def jdkNode = parsedXml.component[].orderEntry.find { it.'@type' == 'jdk' }
            parsedXml.component[].remove(jdkNode)
            def sdkString = "Android API " + android.compileSdkVersion.substring("android-".length()) + " Platform"
            new Node(parsedXml.component[], 'orderEntry', ['type': 'jdk', 'jdkName': sdkString, 'jdkType': 'Android SDK'])
            groovy.xml.XmlUtil.serialize(parsedXml, new FileOutputStream(imlFile))
        } catch (FileNotFoundException e) {
            // nop, iml not found
        }
    }
}

或者找到对应Module下的.iml ，手动修改jar包引入顺序

把Android SDK的配置项放到最后，否则还是会提示找不到系统API：

打印指定 TAG/等级 的log：  logcat LedHal:I *:S

4.编译错误：

a. java.lang.OutOfMemoryError: GC overhead limit exceeded
解决方法： build.gradle中添加：

dexOptions {
    javaMaxHeapSize "4g"
}

b. Too many field references
Building Apps with Over 65K Methods
https://developer.android.com/tools/building/multidex.html

解决方法：

    defaultConfig {

        // Enabling multidex support.
        multiDexEnabled true
    }

dependencies {

    compile 'com.android.support:multidex:1.0.0'

}

　　AndroidManifest.xml 中添加：android:name="android.support.multidex.MultiDexApplication"

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.thisway.app_0001_leddemo" >

    <application
android:name="android.support.multidex.MultiDexApplication"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

c. Error: Invoke-customs are only supported starting with Android O (--min-api 26)

com.android.builder.dexing.DexArchiveBuilderException: com.android.builder.dexing.DexArchiveBuilderException: Failed to process D:\work\AndroidStudioPrj\APP_0001_LEDDemo\settingsLib\settingsLib.jar
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at java.util.concurrent.ForkJoinTask.getThrowableException(ForkJoinTask.java:593)
    at java.util.concurrent.ForkJoinTask.reportException(ForkJoinTask.java:677)
    at java.util.concurrent.ForkJoinTask.join(ForkJoinTask.java:720)
    at com.android.ide.common.internal.WaitableExecutor.waitForTasksWithQuickFail(WaitableExecutor.java:146)
    at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.transform(DexArchiveBuilderTransform.java:405)
    at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:239)
    at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:235)
    at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:102)
    at com.android.build.gradle.internal.pipeline.TransformTask.transform(TransformTask.java:230)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
    at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:50)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:124)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:113)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:95)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:73)
    at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
    at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:101)
    at org.gradle.api.internal.tasks.execution.FinalizeInputFilePropertiesTaskExecuter.execute(FinalizeInputFilePropertiesTaskExecuter.java:44)
    at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:91)
    at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:62)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:256)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:249)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:238)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:663)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:597)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:745)
Caused by: com.android.builder.dexing.DexArchiveBuilderException: Failed to process D:\work\AndroidStudioPrj\APP_0001_LEDDemo\settingsLib\settingsLib.jar
    at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.launchProcessing(DexArchiveBuilderTransform.java:900)
    at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.lambda$convertToDexArchive$6(DexArchiveBuilderTransform.java:825)
    at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
Caused by: com.android.builder.dexing.DexArchiveBuilderException: Error while dexing.
The dependency contains Java 8 bytecode. Please enable desugaring by adding the following to build.gradle
android {
    compileOptions {
        sourceCompatibility 1.8
        targetCompatibility 1.8
    }
}
See https://developer.android.com/studio/write/java8-support.html for details. Alternatively, increase the minSdkVersion to 26 or above.

5. 问服务使用反射

import android.os.IBinder;

        try {
            //iLedService = ILedService.Stub.asInterface(ServiceManager.getService("led"));
            Method getService = Class.forName("android.os.ServiceManager").getMethod("getService", String.class);
            Object ledService = getService.invoke(null, "led"); //static对象第一次参数可以是NULL，调用invoke IBinder向上转换为Object，如有使用IBinder返回需强制转换
            Method asInterface = Class.forName("android.os.ILedService$Stub").getMethod("asInterface", IBinder.class);
            proxy = asInterface.invoke(null, ledService);
            ledCtrl = Class.forName("android.os.ILedService$Stub$Proxy").getMethod("ledCtrl", int.class, int.class);  //设置第i盏灯熄灭： ledCtrl.invoke(proxy, i, 0);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }