JAVA接口继承、抽象类等

package test.intefaces;

public interface TestIntefaceA {
    void testA();
    void testB();
    void testC();
}

package test.intefaces.impl;

import test.intefaces.TestIntefaceA;

public abstract  class TestAbstractImplA implements TestIntefaceA {

    @Override
    public void testA() {
        
    }
    public void testNewD()
    {
        System.out.println("新追加的方法！");
    }
}

package test.intefaces.impl;

import test.intefaces.TestIntefaceA;

public class TestImplA1 extends TestAbstractImplA {
    @Override
    public void testA(){
        // 父类抽（抽象类已经实现了该方法，可以重写，也可以不重写，不会出错）
    }
    
　　// 必须要有
    @Override
    public void testB() {
        // TODO Auto-generated method stub
    }

    @Override
    public void testC() {　　// 必须要有
        // TODO Auto-generated method stub
    }
}

package test.intefaces.impl;

public class TestImplA2 extends TestAbstractImplA {

    @Override
    public void testB() {
        // TODO Auto-generated method stub
    }

    @Override
    public void testC() {
        // TODO Auto-generated method stub
    }
}