//1. 獲取 AMS 的代理對(duì)象 ActivityManager
ActivityManager am = (ActivityManager) context
                    .getSystemService(Context.ACTIVITY_SERVICE);
//2. 調(diào)用相關(guān)API 獲取頂層activity的名稱
String activityName = am.getRunningTasks(1).get(0).topActivity.getClassName();

public class User {
    private String name = "墨子"; //私有變量
    public int age = 18;
    //私有方法
    private int test() {
        System.out.println("私有成員方法");
        return 1;
    }
    protected String test2() {
        System.out.println("protected成員方法");
        return "protected";
    }
    public static void main(String[] args) {
        //如果在本類中創(chuàng)建了對(duì)象，則所有的方法和變量都可以直接訪問
        User user = new User();
        System.out.println(user.name); //訪問私有變量
        System.out.println(user.test());//調(diào)用私有方法
    }
}

public class PrivateTest {
    public static void main(String[] args) {
        User user = new User();
        //外部?jī)?nèi)中創(chuàng)建的對(duì)象直接私有變量  報(bào)錯(cuò)
        //System.out.println(user.name);
        //外部?jī)?nèi)中創(chuàng)建的對(duì)象，直接調(diào)用private方法，也報(bào)錯(cuò)
        //System.out.println(user.test());
        //但是可以直接訪問 protected public的方法和變量
        System.out.println(user.age);
        System.out.println(user.test2());
    }
}

package com.example.javademo.reflect;
public class ClassObject {
    public static void main(String[] args) throws ClassNotFoundException {
        //第一種： 對(duì)象.getClass()；
        People people = new People();
        Class clazz1 = people.getClass();
        System.out.println(clazz1);
        //第二種： 類名.class
        Class clazz2 = People.class;
        System.out.println(clazz2);
        //第三種： Class.forName(包名.類名)
        Class clazz3 = Class.forName("com.example.javademo.reflect.People");
        System.out.println(clazz3);
    }
}

package com.example.javademo.reflect;
public class People {
    private String name;
    private int age;
    public String sex;
    private long height;
    public People() {
        System.out.println("調(diào)用了public無參構(gòu)造方法 執(zhí)行完畢");
    }
    public People(String name) {
        this.name = name;
        System.out.println("調(diào)用public有參構(gòu)造方法 String：name = " + name);
    }
    private People(int age, String sex) {
        this.age = age;
        this.sex = sex;
        System.out.println("調(diào)用private有參數(shù)構(gòu)造方法 age ："+ age + "  sex:" + sex);
    }
    People(long height) {
        this.height = height;
        System.out.println("調(diào)用default有參數(shù)構(gòu)造方法 height ："+ height );
    }
}

package com.example.javademo.reflect;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
public class ReflectPeople {
    public static void main(String[] args) {
        try {
            //獲取People class對(duì)象
            Class peopleclass = Class.forName("com.example.javademo.reflect.People");
            System.out.println("**********************獲取反射后類對(duì)象*********************************");
            System.out.println("反射類對(duì)象：　" + peopleclass);
            //獲取所有構(gòu)造方法
            System.out.println("**********************打印所有構(gòu)造方法*********************************");
            Constructor[] conArray = peopleclass.getDeclaredConstructors();
            for(Constructor c : conArray){
                System.out.println(c);
            }
            System.out.println("**************第一種：通過反射調(diào)用默認(rèn)無參構(gòu)造方法并創(chuàng)建people類實(shí)例對(duì)象***************************");
            //返回一個(gè) Constructor對(duì)象， 該對(duì)象反映Constructor對(duì)象表示的類的指定的公共類函數(shù)。
            Object constructorPublic = peopleclass.getConstructor();
            System.out.println("無參構(gòu)造方法的對(duì)象：" + peopleclass.getConstructor());
            //使用此 Constructor對(duì)象表示的構(gòu)造函數(shù)，使用指定的初始化參數(shù)來創(chuàng)建和初始化構(gòu)造函數(shù)的聲明類的新實(shí)例。
            //newInstance()方法內(nèi)部實(shí)際上調(diào)用了無參數(shù)構(gòu)造方法，必須保證無參構(gòu)造存在才可以
            Object peopleobject1 = ((Constructor) constructorPublic).newInstance();
            System.out.println("創(chuàng)建people1對(duì)象新實(shí)例: " + (People)peopleobject1);
            System.out.println("**************第二種：通過反射調(diào)用public有參構(gòu)造方法并創(chuàng)建People類實(shí)例對(duì)象***************************");
            Object peopleobject2 = peopleclass.getConstructor(String.class).newInstance("甲方");
            System.out.println("創(chuàng)建people2對(duì)象新實(shí)例: " + (People)peopleobject2);
            System.out.println("**************第三種：通過反射調(diào)用private有參構(gòu)造方法并創(chuàng)建People類實(shí)例對(duì)象***************************");
            //注意，如果訪問protect private相關(guān)的構(gòu)造方法，需要用getDeclaredConstructor這個(gè)ＡＰＩ
            //返回一個(gè) Constructor對(duì)象，該對(duì)象反映 Constructor對(duì)象表示的類或接口的指定類函數(shù)。
            Constructor constructorPrivate = peopleclass.getDeclaredConstructor(int.class, String.class);
            //訪問私有構(gòu)造方法，這句話一定要寫，不然就會(huì)報(bào)錯(cuò)java.lang.IllegalAccessException
            constructorPrivate.setAccessible(true);
            System.out.println("有參private私有構(gòu)造方法的對(duì)象：" + peopleclass.getDeclaredConstructor(int.class, String.class));
            Object peopleobject3 = constructorPrivate.newInstance(20, "men");
            System.out.println("創(chuàng)建people3對(duì)象新實(shí)例: " + peopleobject3);
            System.out.println("**************第四種：通過反射調(diào)用default有參構(gòu)造方法并創(chuàng)建People類實(shí)例對(duì)象***************************");
            Constructor constructorDefault = peopleclass.getDeclaredConstructor(long.class);
            //訪問public protect default構(gòu)造方法，這句話可以不用寫
            //constructorDefault.setAccessible(true);
            System.out.println("有參default構(gòu)造方法的對(duì)象：" + peopleclass.getDeclaredConstructor(long.class));
            Object peopleobject4 = constructorDefault.newInstance(185);
            System.out.println("創(chuàng)建people4對(duì)象新實(shí)例: " + peopleobject4);
        } catch (ClassNotFoundException | NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
}

package com.example.javademo.reflect;
public class MethodTest {
    public MethodTest() {
        System.out.println("調(diào)用  MethodTest默認(rèn)的共有構(gòu)造方法");
    }
    String fruit = "蘋果";
    int milliliter = 0;
    char game = 'Ｘ';
    String mood = "開心";
    public void eat(String fruit) {
        this.fruit = fruit;
        System.out.println("調(diào)用public成員方法 eat  吃的水果為 ：" + fruit);
    }
    int drink(int milliliter) {
        this.milliliter = milliliter;
        System.out.println("調(diào)用default成員方法 drink 喝水毫升量 ：" + milliliter);
        return milliliter;
    }
    protected void play(char game) {
        this.game = game;
        System.out.println("調(diào)用protected成員方法 play 玩游戲 ：" + game);
    }
    private String happy(String mood) {
        this.mood = mood;
        System.out.println("調(diào)用private成員方法 happy 今日心情：" + mood);
        return mood;
    }
}

package com.example.javademo.reflect;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
public class ReflectMethod {
    public static void main(String[] args) {
        try {
            System.out.println("**********************獲取反射后類對(duì)象*********************************");
            //獲取方法類的class對(duì)象
            Class methodClass = Class.forName("com.example.javademo.reflect.MethodTest");
            System.out.println("反射類對(duì)象 :" + methodClass);
            System.out.println("**********************獲取反射類中所有的成員方法**************************");
            //返回一個(gè)"方法數(shù)組對(duì)象"：反射類或接口中所有聲明的方法，包括公共，保護(hù)，默認(rèn)（包）訪問和私有方法，但不包括繼承的方法。
            Method[] methods = methodClass.getDeclaredMethods();
            for (Method m : methods) {
                System.out.println(m);
            }
            System.out.println("***************第一種*******調(diào)用反射類中public成員方法**************************");
            //返回一個(gè)方法對(duì)象，它表示此表示的類或接口的指定聲明的方法對(duì)象。
            //第一個(gè)參數(shù)為方法名，第二個(gè)可變參數(shù) : 為該方法傳入的參數(shù)
            Method methodPublic = methodClass.getDeclaredMethod("eat", String.class);
            //PUBLIC :1     PRIVATE:2    PROTECTED:4   PACKAGE(default):8
            System.out.println("打印該public方法的修飾符 ：" + methodPublic.getModifiers());
            System.out.println("打印該public方法對(duì)象 表示方法的名稱： "+methodPublic.getName());
            System.out.println("打印該public方法對(duì)象 可執(zhí)行文件的形式參數(shù)的數(shù)量 ：" + methodPublic.getParameterCount());
            //實(shí)例化一個(gè)MethodTest類對(duì)象，每個(gè)類有一個(gè)默認(rèn)的無參構(gòu)造方法，可以寫或不寫
            //但是如果類中有帶參數(shù)的構(gòu)造方法，那無參構(gòu)造方法是必須要寫出來的，不然new對(duì)象的時(shí)候，就會(huì)報(bào)錯(cuò)
            MethodTest objMethodTest = (MethodTest)methodClass.getDeclaredConstructor().newInstance();
            System.out.println("MethodTest類對(duì)象 :" + objMethodTest);
            //invoke方法 第一個(gè)參數(shù)： 從底層方法被調(diào)用的對(duì)象   如果底層方法是靜態(tài)的，則第一個(gè)參數(shù)obj對(duì)象傳遞null。
            //第二個(gè)參數(shù): 該方法調(diào)用的參數(shù)
            //如果方法正常完成，則返回的值將返回給調(diào)用者.
            Object objectreturn1 = methodPublic.invoke(objMethodTest, "菠蘿");
            //eat方法返回值為 null
            System.out.println("eat方法 返回值為 ：" + objectreturn1);
            System.out.println("***************第二種*******調(diào)用反射類中private成員方法**************************");
            Method methodPrivate = methodClass.getDeclaredMethod("happy", String.class);
            System.out.println("打印該private方法的修飾符 ：" + methodPrivate.getModifiers());
            System.out.println("打印該private方法對(duì)象 表示方法的名稱： "+methodPrivate.getName());
            System.out.println("打印該public方法對(duì)象 可執(zhí)行文件的形式參數(shù)的數(shù)量 ：" + methodPrivate.getParameterCount());
            //如果是訪問私有方法，則要加上這句話,禁止java語言使用時(shí)安全檢查
            methodPrivate.setAccessible(true);
            Object objectreturn2 = methodPrivate.invoke(objMethodTest, "超級(jí)nice");
            System.out.println("happy方法 返回值為："+objectreturn2);
            System.out.println("***************第三種*******調(diào)用反射類中protected成員方法**************************");
            Method methodProtected = methodClass.getDeclaredMethod("play", char.class);
            System.out.println("打印該protected方法的修飾符 ：" + methodProtected.getModifiers());
            System.out.println("打印該protected方法對(duì)象 表示方法的名稱： "+methodProtected.getName());
            System.out.println("打印該protected方法對(duì)象 可執(zhí)行文件的形式參數(shù)的數(shù)量 ：" + methodProtected.getParameterCount());
            Object objectreturn3 = methodProtected.invoke(objMethodTest, 'Y');
            System.out.println("play方法 返回值為："+objectreturn3);
            System.out.println("***************第四種*******調(diào)用反射類中default成員方法**************************");
            Method methodDefault = methodClass.getDeclaredMethod("drink", int.class);
            System.out.println("打印該protected方法的修飾符 ：" + methodDefault.getModifiers());
            System.out.println("打印該protected方法對(duì)象 表示方法的名稱： "+methodDefault.getName());
            System.out.println("打印該protected方法對(duì)象 可執(zhí)行文件的形式參數(shù)的數(shù)量 ：" + methodDefault.getParameterCount());
            Object objectreturn4 = methodDefault.invoke(objMethodTest, 180);
            System.out.println("drink方法 返回值為："+objectreturn4);
        } catch (ClassNotFoundException | NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
}

package com.example.javademo.reflect;
/**
 * desc   : 供反射調(diào)用的FieldTest類
 * version: 1.0
 */
public class FieldTest {
    public FieldTest() {
        System.out.println("調(diào)用FieldTest 默認(rèn)無參構(gòu)造方法");
    }
    public int age = 18;
    private String name = "張三";
    String sex = "男";
    protected String phoneNum = "123456789";
    public int getAge() {
        return age;
    }
    public String getName() {
        return name;
    }
    public String getSex() {
        return sex;
    }
    public String getPhoneNum() {
        return phoneNum;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public void setName(String name) {
        this.name = name;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    public void setPhoneNum(String phoneNum) {
        this.phoneNum = phoneNum;
    }
    @Override
    public String toString() {
        return "FieldTest{" +
                "age=" + age +
                ", name='" + name + '\'' +
                ", sex='" + sex + '\'' +
                ", phoneNum='" + phoneNum + '\'' +
                '}';
    }

package com.example.javademo.reflect;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
 * desc   : 反射FiledTest類中各字段（Field）的實(shí)現(xiàn)類
 * version: 1.0
 */
public class ReflectField {
    public static void main(String[] args) {
        //用正常的new對(duì)象的方式，給字段賦值，打印對(duì)象值， 測(cè)試用
       /* FieldTest objcetFieldTest = new FieldTest();
        objcetFieldTest.setAge(15);
        objcetFieldTest.setName("xiaomao");
        objcetFieldTest.setPhoneNum("12345678");
        objcetFieldTest.setSex("男");
        System.out.println(objcetFieldTest.toString());*/
        //通過反射的方式，修改字段值
        try {
            //通過反射獲取Class對(duì)象
            Class FieldTestClass = Class.forName("com.example.javademo.reflect.FieldTest");
            //用反射的方式來修改字段（成員變量）的值
            System.out.println("************獲取所有的字段(包括共有、私有、受保護(hù)、默認(rèn)的)********************");
            Field[] fields = FieldTestClass.getDeclaredFields();
            for (Field f : fields) {
                System.out.println(f);
            }
            //用反射的方式來構(gòu)造FieldTestl類對(duì)象
            FieldTest objFieldTest = (FieldTest) FieldTestClass.getDeclaredConstructor().newInstance();
            System.out.println("*************反射獲取public字段并調(diào)用***********************************");
            //返回一個(gè) Field對(duì)象，它表示的類或接口的指定已聲明字段對(duì)象。
            Field fieldPublic =  FieldTestClass.getDeclaredField("age");
            System.out.println("該字段的修飾符 ：" + fieldPublic.getModifiers());
            System.out.println("該字段的名稱 ：" + fieldPublic.getName());
            /*
            * 獲取字段的值：有 getInt(Object obj) getLong(Object obj) get(Object obj)等方法
            *
            * obj ：為通過反射方法 構(gòu)造出來的類對(duì)象
            * */
            //獲取int類型 實(shí)例字段的默認(rèn)值
            System.out.println("通過反射方式獲取age默認(rèn)值 ： " + fieldPublic.getInt(objFieldTest));
           /* 設(shè)置字段的值：
 		    Field  public void set(Object obj,Object value):
 			參數(shù)說明：
				1.obj: 通過反射方法 構(gòu)造出來的類對(duì)象
 				2.value:要為字段設(shè)置的值；
 		   */
            fieldPublic.set(objFieldTest, 20);
            //通過反射的方式調(diào)用 getAge() 方法
            Method method = FieldTestClass.getDeclaredMethod("getAge");
            Object objectReturn =  method.invoke(objFieldTest);
            System.out.println("通過反射方式set新值之后， age的值 ：" + objectReturn);
            System.out.println("*************反射獲取private字段并調(diào)用***********************************");
            //在項(xiàng)目實(shí)際中，因?yàn)樗接凶兞亢头椒ǎ瑹o法在外部類去調(diào)用它們，所以反射在這點(diǎn)上就派上用場(chǎng)了
            Field fieldPrivate = FieldTestClass.getDeclaredField("name");
            //private字段一定要調(diào)用setAccessible(true)  禁止java語言使用時(shí)安全檢查
            fieldPrivate.setAccessible(true);
            System.out.println("通過反射方式獲取age默認(rèn)值 ： " + fieldPrivate.get(objFieldTest));
            //修改private變量name的值
            fieldPrivate.set(objFieldTest, "李四");
            //通過反射的方式調(diào)用 getName() 方法
            Method objectMethod = FieldTestClass.getDeclaredMethod("getName");
            Object objectReturn1 =  objectMethod.invoke(objFieldTest);
            System.out.println("通過反射方式set新值之后， name的值 ：" + objectReturn1);
        } catch (ClassNotFoundException | NoSuchMethodException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }
    }

package com.example.javademo.reflect;
public class StaticFieldTest {
    public StaticFieldTest() {
        System.out.println("調(diào)用 StaticFieldTest 無參構(gòu)造方法");
    }
    //靜態(tài)變量
    public static int age = 15;
    public static void setAge(int age) {
        StaticFieldTest.age = age;
    }
    //靜態(tài)方法
    public static int getAge() {
        return age;
    }
}

package com.example.javademo.reflect;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
public class ReflectStatic {
    public static void main(String[] args) {
        try {
            //獲取 StaticFieldTest  class對(duì)象
            Class staticClazz = Class.forName("com.example.javademo.reflect.StaticFieldTest");
            //獲取靜態(tài)Field對(duì)象
            Field staticField = staticClazz.getDeclaredField("age");
            //因?yàn)槭莗ulic修飾符，這句話也可以不用寫
            staticField.setAccessible(true);
            //通過set方法，修改值,  靜態(tài)變量 是從屬于類，可以不用傳入類實(shí)例對(duì)象，直接傳入null
            staticField.set(null, 25);
            //驗(yàn)證修改后的值
            Method agetet = staticClazz.getDeclaredMethod("getAge");
            // 靜態(tài)方法 是從屬于類， 可以不用傳入類實(shí)例對(duì)象，直接傳入null
            int agetest = (int) agetet.invoke(null);
            System.out.println("**********************打印修改后的age值**************************");
            System.out.println(agetest);
        } catch (ClassNotFoundException | NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }
    }

 /**
     * @description: 通過反射方式獲取 頂層activity名稱
     * @param: null
     * @return: boolean 如果是目標(biāo)activity 則返回true
    */
    public boolean isTopTargetActivity() {
        try {
            //通過包名和類名反射獲取 class 對(duì)象
            Class activityThreadClass = Class.forName("android.app.ActivityThread");
            //第二種： 反射創(chuàng)建 activiyThread對(duì)象  反射調(diào)用靜態(tài)方法，第一個(gè)參數(shù)obj對(duì)象傳遞 null
            Object activityThreadObj = activityThreadClass.getMethod("currentActivityThread").invoke(null);
            Log.e("test", "====activityThreadObj: "+activityThreadObj);
            //獲取 mActivities Field對(duì)象  final ArrayMap<IBinder, ActivityClientRecord> mActivities = new ArrayMap<>();
            Field activitiesField = activityThreadClass.getDeclaredField("mActivities");
            //禁止Java語言訪問使用時(shí)進(jìn)行檢查
            activitiesField.setAccessible(true);
            //返回該所表示的字段的值 Field
            Map activities = (Map) activitiesField.get(activityThreadObj);
            for (Object activityClientRecord : activities.values()) {
                //獲取 ActivityClientRecord class對(duì)象
                Class activityRecordClass = activityClientRecord.getClass();
                //獲取 boolean paused 字段 對(duì)象
                Field pausedField = activityRecordClass.getDeclaredField("paused");
                //允許暴力訪問，禁止java語言運(yùn)行時(shí)安全檢查
                pausedField.setAccessible(true);
                //Activity onResume的判斷條件
                if (!pausedField.getBoolean(activityClientRecord)) {
                    //獲取 Activity activity field對(duì)象
                    Field activityField = activityRecordClass.getDeclaredField("activity");
                    activityField.setAccessible(true);
                    //獲取當(dāng)前顯示的activity的對(duì)象
                    Activity activity = (Activity) activityField.get(activityClientRecord);
                    //獲取當(dāng)前activity的名稱
                    String className = activity.getClass().toString();
                    Log.e("test", "====通過反射獲取的className===="+className);
                    if ("cn.com.test.activity.MainActivity".equals(className)) {
                        return true;
                    }
                }
            }
        } catch (ClassNotFoundException e) {
            Log.e("test", "======ClassNotFoundException===="+e.getMessage());
        } catch (InvocationTargetException e) {
            Log.e("test", "======InvocationTargetException===="+e.getMessage());
        } catch (NoSuchMethodException e) {
            Log.e("test", "======NoSuchMethodException===="+e.getMessage());
        } catch (NoSuchFieldException e) {
            Log.e("test", "======NoSuchFieldException===="+e.getMessage());
        } catch (IllegalAccessException e) {
            Log.e("test", "======IllegalAccessException===="+e.getMessage());
        }
        return false;
    }

public class SystemPropertiesUtils {
    private static final String TAG = "SystemPropertiesUtils";
    private static Class<?> mClassType = null;
    private static Method mGetMethod = null;
    private static Method mGetIntMethod = null;
    private static Method mGetBooleanMethod = null;
    private static Class<?> getSystemPropertiesClass() throws ClassNotFoundException {
        if (mClassType == null) {
            mClassType = Class.forName("android.os.SystemProperties");
        }
        return mClassType;
    }
    private static Method getMethod() throws Exception {
        if (mGetMethod == null) {
            Class clazz = getSystemPropertiesClass();
            mGetMethod = clazz.getDeclaredMethod("get", String.class);
        }
        return mGetMethod;
    }
    private static Method getIntMethod() throws Exception {
        if (mGetIntMethod == null) {
            Class clazz = getSystemPropertiesClass();
            mGetIntMethod = clazz.getDeclaredMethod("getInt", String.class, int.class);
        }
        return mGetIntMethod;
    }
    private static Method getBooleanMethod() throws Exception {
        if (mGetBooleanMethod == null) {
            Class clazz = getSystemPropertiesClass();
            mGetBooleanMethod = clazz.getDeclaredMethod("getBoolean", String.class, boolean.class);
        }
        return mGetBooleanMethod;
    }
    public static String get(String key, String def) {
        try {
            String value = (String) getMethod().invoke(null, key);
            if (!TextUtils.isEmpty(value)) {
                return value;
            }
        } catch (Exception e) {
            Log.d(TAG, "Unable to read system properties");
        }
        return def;
    }
    public static int getInt(String key, int def) {
        int value = def;
        try {
            value = (int) getIntMethod().invoke(null, key, def);
        } catch (Exception e) {
            Log.d(TAG, "Unable to read system properties");
        }
        return value;
    }
    public static boolean getBoolean(String key, boolean def) {
        boolean value = def;
        try {
            value = (Boolean) getBooleanMethod().invoke(null, key, def);
        } catch (Exception e) {
            Log.d(TAG, "Unable to read system properties");
        }
        return value;
    }
}

public static Bitmap createVideoThumbnail(String filePath) {
        // MediaMetadataRetriever is available on API Level 8
        // but is hidden until API Level 10
        Class<?> clazz = null;
        Object instance = null;
        try {
            clazz = Class.forName("android.media.MediaMetadataRetriever");
            instance = clazz.newInstance();
 
            Method method = clazz.getMethod("setDataSource", String.class);
            method.invoke(instance, filePath);
 
            // The method name changes between API Level 9 and 10.
            if (Build.VERSION.SDK_INT <= 9) {
                return (Bitmap) clazz.getMethod("captureFrame").invoke(instance);
            } else {
                byte[] data = (byte[]) clazz.getMethod("getEmbeddedPicture").invoke(instance);
                if (data != null) {
                    Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
                    if (bitmap != null) return bitmap;
                }
                return (Bitmap) clazz.getMethod("getFrameAtTime").invoke(instance);
            }
        } catch (IllegalArgumentException ex) {
            // Assume this is a corrupt video file
        } catch (RuntimeException ex) {
            // Assume this is a corrupt video file.
        } catch (InstantiationException e) {
            Log.e(TAG, "createVideoThumbnail", e);
        } catch (InvocationTargetException e) {
            Log.e(TAG, "createVideoThumbnail", e);
        } catch (ClassNotFoundException e) {
            Log.e(TAG, "createVideoThumbnail", e);
        } catch (NoSuchMethodException e) {
            Log.e(TAG, "createVideoThumbnail", e);
        } catch (IllegalAccessException e) {
            Log.e(TAG, "createVideoThumbnail", e);
        } finally {
            try {
                if (instance != null) {
                    clazz.getMethod("release").invoke(instance);
                }
            } catch (Exception ignored) {
            }
        }
        return null;
    }