十三 java面向对象程序设计(初始化A)
/**
* 初始化(一)
* 成员变量和构造机的初始化过程
* 1,成员变量的初始化:
* 2,构造方法的执行顺序:
* 3,静态成员的执行顺序;
* 4,静态代码块的执行顺序;
*/
/* 一,成员初始化 */
class MemberInitialization
{
/*1,自动初始化*/
private boolean b;
private char c;
private byte by;
private short s;
private int i;
private long l;
private float f;
private double d;
private String str;
private MemberInitialization obj;
public void printInfo1(){
System.out.println(
"boolean " + b + "\n" +
"char " + c + "\n" +
"byte " + by + "\n" +
"short " + s + "\n" +
"int " + i + "\n" +
"long " + l + "\n" +
"float " + f + "\n" +
"double " + d + "\n" +
"String " + str + "\n" +
"reference " + obj
);//类中的成员变量即使没有为他们赋初值,也将会自动初始化.
/*但是在这个方法中定义的变量在使用前没有初始化将提示一个错误.
int i;
i++;
*/
}
/*2,指定初始化*/
//(1),在定义变量的地方初始化.
private boolean bl = true;
private char ch = 'a';
private byte bt = 0;
private short sh = 10;
private int in = 20;
private long lg = 30;
private float fl = 0.0f;
private double dl = 1.0;
private String strg = "string";
private MemberInitialization ob = this;
public void printInfo2()
{
Sys
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
public class test {
public static void main(String[] args) {
ArrayList<ArrayList<Integer>> list = getArrays(1, 20, 30);
Iterator<ArrayList<Integer>> iter = list.itera ......
