java第一天

package com.cjwproduct;

/**

 * 

 * @author CJW

 * @fistprod 第一个个工程

 */

public class fistprod {

  public static void main(String[] args)

  {

  //第一行代码helloWord

  String myString = "我是hellowrold";

  final String SET = "男";

  System.out.println(SET);

  System.out.println("我是第一个java文件"+myString);

 

 

  //运算符 加法；

  int a = 10;

  int b = 20;

  int sum = a+b;

  System.out.println("运算结果是："+sum);

  //自增，自减 ++ --

  int a1 = 5;

  int b1 = ++a1;//让a先执行自增，然后将值赋值给变量b

  System.out.println("a1:"+a1);

  System.out.println("b1:"+b1);

 

  //

  int a2 = 5;

  int b2 = a2++;//让a的值赋值给变量b，然后在执行自增

  System.out.println("a2:"+a2);

  System.out.println("b2:"+b2);

  //-= += *= /= %=

 

  int one = 10;

  int two = 20;

  int three = 0;

  three = one + two;

  System.out.println("three:"+three);

  three += one;

  System.out.println("three1:"+three);

  three -= one;

  System.out.println("three2:"+three);

  three *=one; 

  System.out.println("three:"+three);

    

 

  //java 比较运算符

  int m = 16;

  double h = 9.5;

  String str1 = "hello";

  String Str2 = "MY Love is You";

  System.out.println("m等于h:"+(m == h));

  System.out.println("m大于h:"+(m > h));

  System.out.println("m小于h:"+(m <= h));

  System.out.println("str1等于str2:"+(str1 == Str2));

 

  //java 逻辑运算符

  boolean aa = true;

  boolean bb = false;

  boolean cc = false;

  boolean dd = true;

  System.out.println((aa && bb)+"未通过");

  System.out.println((aa || dd)+"通过");

  System.out.println((!aa)+"未通过");

  System.out.println((cc ^ dd)+"通过");

 

  //java 中的条件运算符

  String str = (8>5) ? "8大于5" : "8不大于5";

  System.out.println(str);

  }

}