java结果输出，知其所以然

[java]
代码输出结果是什么？为什么会出现这种结果？
代码一
public class ParentTest {
    public ParentTest(){
        System.out.println("Parent Constructor invoked");
    }
    static{
        System.out.println("parent static invoked");
    }

    {
        System.out.println("parent invoked");
    }
}
public class ChildrenTest extends ParentTest{
    public ChildrenTest(){
        System.out.println("Children Constructor invoked");
    }
    static{
        System.out.println("Children static invoked");
    }

    {
        System.out.println("Children invoked");
    }
    public static void main(String[] args) {
        new ChildrenTest();
    }
}
代码二:true or false
public class MyTest1 {
    private String str;
    public MyTest1(String str){
        this.str=str;
    }
    public static void main(String[] args) {
        MyTest1 m1=new MyTest1("hello");
        MyTest1 m2=new MyTest1("hello");
        System.out.println(m1.equals(m2));
    }
}
代码三:true or false
public class MyTest1 {
    public static void main(String[] args) {
    System.out.println(Integer.valueOf(323)==Integer.valueOf(323));
    System.out.println(Integer.valueOf(23)==Integer.valueOf(23));
    }
}
代码四：
public class MyTest1 {
    private static int a;
    public MyTest1(){
        System.out.println("a="+(++a));
    }
    public void test(){
        int a=5;
        System.out.println("a="+a);
    }
    public void test2(){
        a=5;
        System.out.println("a="+a);
    }
    public static void main(String[] args) {
        new MyTest1();
        new MyTest1();
        new MyTest1().test();
        System.out.println(a);
        new MyTest1().test2();
        System.out.println(a);
    }
}
代码五：
public class Parent {
    public Parent(String name){
        System.out.println(name);
    }
}
public class Children extends Parent{
    public Children(String name){
        System.out.println(name);
    }

    public static void main(String[] args) {
        new Children("hello");
    }
}
作者：HarderXin

补充：软件开发 , Java ,