如果还有其他嵌套，如果在Java中：

> if语句：
如果某个条件为true，则执行一系列语句。

语法：>

//要执行的代码
> }

program:
public class if {  
public static void main(string[] args) {  
      float a =2.2f; 
      float b =5.4f; 
        if(b>a)
         {  
          system.out.println(" b is greater than a");  
           }  
       }  
}  


output:
b is greater than a

> if-else语句： 在java中，if-else条件是一组规则或语句，如果条件为真，则执行一个代码块，如果条件为false，则执行另一个块。

语法：> if（条件）{

} else {
//代码如果条件为false
}

**program**:

public class ifelse {

    public static void main(string[] args) {

        int n = 3;

        if (n > 5) {
            system.out.println("the number is greater than 5.");
        } 
         else  
        {
            system.out.println("the number is 5 or less.");
        }
    }
}


output:
the number is 5 or less.

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if（条件1）{ //如果条件1为true

> //如果条件1为false，并且条件2为true
>，则要执行的代码块 } else {
//如果条件1为false，并且条件2为false
，则要执行的代码块 }

**program:**

public class greater
{
public static void main (string args[])
{
int no1 = 1000; 
        int no2 = 1000; 
        if(no1>no2)
          {
            system.out.println("no1 is greater");
          }
        else if(no2>no1)
         {
              system.out.println("no2 is greater");
         }      
        else 
           {
         system.out.println("both are equal");
           }
}
}

output:
     both are equal

如果 *

if（condition1）{

if（condition3）{ //语句; }

}

program:

    public class nested if
    {
    public static void main(string args[])
    {
        int a = 10;
        int b = 20;

        // outer if condition
        if (a == 10) {

            // inner if condition
            if (b != 20) {
                system.out.println("geeksforgeeks");
            }

            else {
                system.out.println("gfg");
            }
        }
    }
}

public class age
{
public static void main (string args[])
{
 int age1=25;
 int age2=21;
    if(age1




  
  
  python




age1 = 25
age2 = 21

if age1 < age2:
    print("the condition is false")
elif age2 < age1:
    print("the condition is true")

output:
the condition is true





  
  
  爪哇




program:2

public class if {  
public static void main(string[] args) {  
      float a =2.2f; 
      float b =5.4f; 
        if(b>a)
         {  
          system.out.println(" b is greater than a");  
           }  
       }  
}  

output:
b is greater than a






  
  
  python




a = 2.2
      b = 5.4
if b > a:
    print("b is greater than a")

output:
  num is greater than or equal 120






  
  
  爪哇




program:3

public class greater
{
public static void main (string args[])
{
int no1 = 1000; 
        int no2 = 1000; 
        if(no1>no2)
          {
        system.out.println("no1 is greater");
          }
        else if(no2>no1)
         {
           system.out.println("no2 is greater");
         }      
        else 
           {
      system.out.println("both are equal");
           }
}
}

output:
both are equal






  
  
  python




no1 = 1000
no2 = 1000

if no1 > no2:
    print("no1 is greater")
elif no2 > no1:
    print("no2 is greater")
else:
    print("Both are equal")

output:
Both are equal





>参考：
 

参考：
 

参考：
 



          https://www.javatpoint.com/java-if-else