java010301

  public class DataDemo1{51Testing软件测试网r8p6zw8Z%U

         public static void main(String args[]){

               int max = Integer.MAX_VALUE ; //求出最大值

               System.out.println("整型的最大值："+(max)); 51Testing软件测试网]$Y.sg$m

               System.out.println("整型的最大值+1："+(max+1)); 

               System.out.println("整型的最大值+2："+(max+2)); 

               }

         };

D:\java_study\010301>java DataDemo151Testing软件测试网A-xoIy2bo

整型的最大值：2147483647

整型的最大值+1：-214748364851Testing软件测试网g"|~$z ?
|
r

整型的最大值+2：-2147483647

   public class DataDemo3{51Testing软件测试网+r
X9sgv)m2dDk

         public static void main(String args[]){

               int max = Integer.MAX_VALUE ; //求出最大值

               System.out.println("整型的最大值："+(max)); 

               System.out.println("整型的最大值+1："+(max+1)); 51Testing软件测试网4f,~-}/sz1Y/qI7O?c

               System.out.println("整型的最大值+2："+((long)max+2));51Testing软件测试网#`9l.M0Q5J$VoGP

               }51Testing软件测试网 eM'Dp)Ck2UN-I

         };

D:\java_study\010301>java DataDemo351Testing软件测试网Ft p*@o

整型的最大值：2147483647

整型的最大值+1：-214748364851Testing软件测试网.{"d'PUW

整型的最大值+2：2147483649

   public class DataDemo5{

         public static void main(String args[]){

               char ch1 = '\"' ; // 表示一个双引号；51Testing软件测试网U'F,s9l/wvdGP3M

               char ch2 = '\\' ;  //通过数字定义字符变量

               System.out.println("ch1 = "+ch1) ;

               System.out.println("ch2 = "+ch2) ;51Testing软件测试网+MG$N+{~re };E

               System.out.println("\"hello,world\"") ;51Testing软件测试网8B1aD})V3p6j

               }51Testing软件测试网)o![`6@svm

         };51Testing软件测试网 ru @_Z
x"[#Vt

D:\java_study\010301>java DataDemo551Testing软件测试网\e(?:w:^B uc^/xW@

ch1 = "

ch2 = \

"hello,world"

   public class DataDemo6 {

         public static void main(String args[]){51Testing软件测试网}J{kNw

                float num = 3.0f ; //定义一个浮点型数；

                System.out.println("两个小数相乘："+num * num) ;51Testing软件测试网K_c5F7p5l!A&xx

               }51Testing软件测试网X5k8idLp`^I'U

         };

 public class DataDemo7 {

         public static void main(String args[]){51Testing软件测试网0yy[!N y2H

                boolean flag = true ; //定义一个布尔型；

                System.out.println("flag = "+flag) ;51Testing软件测试网}V(_[`z2_

               }

         };51Testing软件测试网8~S|Fjm$UXsM

   public class DataDemo8 {51Testing软件测试网Am'V7A/LL\

         public static void main(String args[]){51Testing软件测试网(_|-B
I7~9D

                String str = "luoriver"; //定义字符串变量

                int x = 30 ;

                str =str + x ; //修改str的内容并将内容重新给str变量51Testing软件测试网,J/FDgz9t2jn

                System.out.println("str= "+ str); 51Testing软件测试网"U$y B?;h)k

               }51Testing软件测试网$x$P(ZGGN

         };51Testing软件测试网tFw9@no

         51Testing软件测试网{8\ V1JZ]%r

D:\java_study\010301>java DataDemo851Testing软件测试网#f\yW&u

str=luoriver30

 public class DataDemo10 {

         public static void main(String args[]){51Testing软件测试网4t.d4Zh
p^

               int x = 1 ; //定义整型变量51Testing软件测试网;Ln)c#D `-U[vwv7{

               int j = 2 ;51Testing软件测试网Z)V4G/hx

                System.out.println("1 + 2 = "+ 1+2); //会输出12，所有的数据类型都会像字符串转换；

            System.out.println("1 + 2 = "+(1+2));//会输出3；

               }

         };

D:\java_study\010301>java DataDemo10

1 + 2 = 12

   public class DataDemo11 {

         public static void main(String args[]){51Testing软件测试网{&_7?e E_jO"nU

                float f = 30.3f ; //浮点型

                int x = (int) f ; //强制类型转换51Testing软件测试网9D9fu.h%w

                System.out.println("x = "+ x);

                System.out.println("10 / 3 = "+ ((float)10/3)); 51Testing软件测试网#N6K"N1B/c*N9Rin

               }

         };51Testing软件测试网.w$h,A$[7}