Java reflection is used in Android, and java reflection android

Java reflection is used in Android, and java reflection android

Reprinted please indicate the source: http://www.cnblogs.com/cnwutianhao/p/6606687.html

 

If you want to call A private Method B in Class A and use it in class C. Generally, direct call of methods does not work. Some people also say that it is time to turn private into public, but there is a solution in everything, and there is no need to change it to public.

Enter the subject:

There is such a piece of code

public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        method();    }    private void method() {    }}

Now we want to use Junit to test the private method in MainActivity.

If we want to test the private method in MainActivity, direct calling will not work, and Java reflection (Reflect) will be used at this time)

First, create the test file MainActivityTest, which inherits AndroidTestCase

public class MainActivityTest extends AndroidTestCase {}

Then, create the test class testMethod

public void testMethod() throws Exception {}

Complete Test code

public class MainActivityTest extends AndroidTestCase {    public void testMethod() throws Exception {        MainActivity activity = new MainActivity();        Method testMethod = MainActivity.class.getDeclaredMethod("method");        testMethod.setAccessible(true);        testMethod.invoke(activity);    }}

Now, we can use the private method in MainActivity!

 

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