Android Crash Handler

CrashHandler.java

import android.app.Activity;
import android.app.ActivityManager;
import android.app.Application;
import android.os.Process;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.text.TextUtils;

import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.List;

/**
 * crash handler
 * Created by kenneth on 2016/12/20.
 */
public class CrashHandler implements Thread.UncaughtExceptionHandler {
    private final Application app;
    private final boolean debug;
    private final String buildTime;
    private final Thread.UncaughtExceptionHandler defaultHandler;
    private final SimpleActivityLifecycleCallbacks lifecycleCallbacks;
    private OnCrashListener onCrashListener;

    public static CrashHandler create(Application app, boolean debug) {
        return new CrashHandler(app, debug, null);
    }

    public static CrashHandler create(Application app, boolean debug, String buildTime) {
        return new CrashHandler(app, debug, buildTime);
    }

    private CrashHandler(Application app, boolean debug, String buildTime) {
        this.app = app;
        this.debug = debug;
        this.buildTime = buildTime;
        defaultHandler = Thread.getDefaultUncaughtExceptionHandler();
        Thread.setDefaultUncaughtExceptionHandler(this);

        lifecycleCallbacks = new SimpleActivityLifecycleCallbacks();
        app.registerActivityLifecycleCallbacks(lifecycleCallbacks);
    }

    public void setOnCrashListener(OnCrashListener onCrashListener) {
        this.onCrashListener = onCrashListener;
    }

    @Override
    public void uncaughtException(Thread thread, Throwable throwable) {
        StringBuilder sb = new StringBuilder();

        addAppDebug(sb);
        addProcessAndThread(sb);
        addActivitiesAndFragments(sb);
        addLeakedActivities(sb);
        addMemoryInfo(sb);

        Throwable crashThrowable = new Throwable(sb.toString(), throwable);
        if (onCrashListener != null) onCrashListener.onCrash(thread, crashThrowable);
        if (defaultHandler != null) defaultHandler.uncaughtException(thread, crashThrowable);
    }

    /**
     * add APP is debug or not
     */
    private void addAppDebug(StringBuilder sb) {
        sb.append("\n");
        sb.append("debug: ").append(debug);
        if (!TextUtils.isEmpty(buildTime)) {
            sb.append(", ");
            sb.append("build: ").append(buildTime);
        }
    }

    /**
     * add process name and current thread name
     */
    private void addProcessAndThread(StringBuilder sb) {
        sb.append("\n");
        int myPid = Process.myPid();
        ActivityManager am = (ActivityManager) app.getSystemService(Application.ACTIVITY_SERVICE);
        for (ActivityManager.RunningAppProcessInfo appProcess : am.getRunningAppProcesses()) {
            if (appProcess.pid == myPid) {
                sb.append("process: ").append(appProcess.processName).append(", ");
                break;
            }
        }
        sb.append("thread: ").append(Thread.currentThread().getName());
    }

    /**
     * add opened activities
     */
    private void addActivitiesAndFragments(StringBuilder sb) {
        sb.append("\n");
        List<Activity> activityList = lifecycleCallbacks.activityList;
        sb.append("activities: ");

        boolean firstTime = true;
        for (Activity activity : activityList) {
            if (firstTime) {
                firstTime = false;
            } else {
                sb.append(",");
            }
            sb.append(activity.getClass().getSimpleName());
            addFragments(sb, activity);
        }
    }

    private void addFragments(StringBuilder sb, Activity activity) {
        if (activity instanceof FragmentActivity) {
            FragmentActivity fragmentActivity = (FragmentActivity) activity;
            FragmentManager fragmentManager = fragmentActivity.getSupportFragmentManager();
            List<Fragment> fragments = fragmentManager.getFragments();
            if (!Utils.isEmpty(fragments)) {
                sb.append("(").append(Utils.getNamesString(fragments)).append(")");
            }
        }
    }

    /**
     * add leaked activities
     */
    private void addLeakedActivities(StringBuilder sb) {
        sb.append("\n");
        List<String> leakedActivityNames = new ArrayList<>();
        List<WeakReference<Activity>> referenceActivities = lifecycleCallbacks.referenceActivities;
        for (WeakReference<Activity> wf : referenceActivities) {
            Activity activity = wf.get();
            if (activity == null) continue;
            if (!lifecycleCallbacks.activityList.contains(activity)) {
                leakedActivityNames.add(activity.getClass().getSimpleName());
            }
        }
        sb.append("leaked activities: ").append(TextUtils.join(",", leakedActivityNames));
    }

    /**
     * add memory information
     */
    private void addMemoryInfo(StringBuilder sb) {
        sb.append("\n");
        Runtime runtime = Runtime.getRuntime();
        float maxMemory = runtime.maxMemory() / 1024 / 1024f;
        float totalMemory = runtime.totalMemory() / 1024 / 1024f;
        float freeMemory = runtime.freeMemory() / 1024 / 1024f;
        sb.append("maxMemory: ").append(maxMemory).append("MB").append(",");
        sb.append("totalMemory: ").append(totalMemory).append("MB").append(",");
        sb.append("freeMemory: ").append(freeMemory).append("MB");
    }

    public interface OnCrashListener {
        void onCrash(Thread thread, Throwable throwable);
    }
}

SimpleActivityLifecycleCallbacks.java

import android.app.Activity;
import android.app.Application;
import android.os.Bundle;

import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.List;

/**
 * Created by kenneth on 2016/12/20.
 */
class SimpleActivityLifecycleCallbacks implements Application.ActivityLifecycleCallbacks {

    List<Activity> activityList = new ArrayList<>();
    List<WeakReference<Activity>> referenceActivities = new ArrayList<>();

    SimpleActivityLifecycleCallbacks() {
    }

    @Override
    public void onActivityCreated(Activity activity, Bundle bundle) {
        activityList.add(activity);
        referenceActivities.add(new WeakReference<>(activity));
    }

    @Override
    public void onActivityStarted(Activity activity) {

    }

    @Override
    public void onActivityResumed(Activity activity) {

    }

    @Override
    public void onActivityPaused(Activity activity) {

    }

    @Override
    public void onActivityStopped(Activity activity) {

    }

    @Override
    public void onActivitySaveInstanceState(Activity activity, Bundle bundle) {

    }

    @Override
    public void onActivityDestroyed(Activity activity) {
        activityList.remove(activity);
    }
}

Utils.java

import android.text.TextUtils;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Created by kenneth on 2016/12/20.
 */

public class Utils {

    static <T> String getNamesString(List<T> list) {
        if (isEmpty(list)) return null;
        return TextUtils.join(",", getClassNames(list));
    }

    private static <T> List<String> getClassNames(List<T> list) {
        if (isEmpty(list)) return null;
        List<String> names = new ArrayList<>();
        for (Object o : list) {
            names.add(o.getClass().getSimpleName());
        }
        return names;
    }

    public static boolean isEmpty(Collection collection) {
        return collection == null || collection.isEmpty();
    }
}