How to check if radio buttons are selected on button click?

I'm Developing an android app in which the Questionnaire activity contains Questions which as radio Buttons and also a Button.So when the button is pressed I've to check whether all the Questions are answered.if the Question is not answered then a alert message should pop up stating that the particular Question no is not answered.Can anyone please help me with the java code. Thanks in Advance.

<RadioGroup
    android:id="@+id/Mquestion1"  
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
<RadioButton
    android:id="@+id/radioButton1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_1_rb1" />

<RadioButton
    android:id="@+id/radioButton2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_1_rb2" />

<RadioButton
    android:id="@+id/radioButton3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_1_rb3" />
</RadioGroup>
<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_2_view"
    android:textAppearance="?android:attr/textAppearanceSmall" />
<RadioGroup
android:id="@+id/Mquestion2"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
    android:id="@+id/radioButton4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_2_rb1" />

<RadioButton
    android:id="@+id/radioButton5"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_2_rb2" />

<RadioButton
    android:id="@+id/radioButton6"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_2_rb3" />
</RadioGroup>
<TextView
    android:id="@+id/textView4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_3_view"
    android:textAppearance="?android:attr/textAppearanceSmall" />
<RadioGroup
android:id="@+id/Mquestion3"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
    android:id="@+id/radioButton7"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_3_rb1" />

<RadioButton
    android:id="@+id/radioButton8"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_3_rb2" />

<RadioButton
    android:id="@+id/radioButton9"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/MQ1_3_rb3" />
</RadioGroup>
<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="44dp" >

    <Button
        android:id="@+id/button1"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:onClick="sendMessage"
        android:text="@string/MQ1_next" />

</RelativeLayout>

</LinearLayout>

and here is the java code

public class ManagerQuestionnaire1 extends Activity
{

Button next;
RadioGroup rg1;
RadioGroup rg2;
RadioGroup rg3;
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_manager_questionnaire1);
    final RadioGroup    rg1=(RadioGroup)findViewById(R.id.Mquestion1);
     final RadioGroup   rg2=(RadioGroup)findViewById(R.id.Mquestion2);
     final RadioGroup   rg3=(RadioGroup)findViewById(R.id.Mquestion3);
    Button next=(Button)findViewById(R.id.button1);
            next.setOnClickListener(new View.OnClickListener()
            {
                public void OnClick(View v) //Here in this line I'm getting a caution symbol which says REMOVE METHOD 'OnClick'
                {

                    if((rg1.getCheckedRadioButtonId()!=R.id.radioButton1 || rg1.getCheckedRadioButtonId()!=R.id.radioButton2 || rg1.getCheckedRadioButtonId()!=R.id.radioButton3)||(rg2.getCheckedRadioButtonId()!=R.id.radioButton4 || rg2.getCheckedRadioButtonId()!=R.id.radioButton5 || rg2.getCheckedRadioButtonId()!=R.id.radioButton6)||(rg3.getCheckedRadioButtonId()!=R.id.radioButton7 || rg3.getCheckedRadioButtonId()!=R.id.radioButton8 || rg3.getCheckedRadioButtonId()!=R.id.radioButton9))
                    {
                         AlertDialog alert= new AlertDialog.Builder(ManagerQuestionnaire1.this).create();
                         alert.setTitle("Exception:Complete the Questions");
                         alert.setMessage("Please ensure all Questions are answered");
                    }
                    else    
                    {
                         Intent intent = new Intent(ManagerQuestionnaire1.this, ManagerQuestionnaire2.class);
                            startActivity(intent);
                    }
                }

                @Override
                public void onClick(View v) 
                {
                    // TODO Auto-generated method stub

                }


    });
}