java例

例一：

class DataDemo01{
public static void main(String[] args){
int num =999999999999999999999999;
}
}

例二：

class DataDemo02{
public static void main(String[] args){
int max =Integer.MAX_VALUE;
System.out.println("整型的最大值："+max);
System.out.println("整型最大值 +1："+(max+1));
System.out.println("整型最大值 +2："+(max+2));
}

}

例三：

public class DataDemo03{
public static void main(String[] args){
int max =Integer.MAX_VALUE;
System.out.println("整型的最大值："+max);
System.out.println("整型最大值 +1："+(max+1));
System.out.println("整型最大值 +2："+(max+2L));
System.out.println("整型最大值 +2："+((long)max+2));
}
}

例四：

public class DataDemo04{
public static void main(String[] args){
char ch1='a';
char ch2=97;
System.out.println("ch1 = "+ch1);
System.out.println("ch2 = "+ch2);

}
}

例五：

public class DataDemo05{
public static void main(String[] args){
char ch1='"';
char ch2='\';
System.out.println("ch1 = "+ch1);
System.out.println("ch2 = "+ch2);
System.out.println(""Hello World"");
}
}

例六：

public class DataDemo06{
public static void main(String[] args){
float num=3.0f;
System.out.println("两个小数相乘："+num*num);
}
}

例七：

public class DataDemo07{
public static void main(String[] args){
boolean flag=true;
System.out.println("flag = "+flag);
}
}