Java StringBuilder reverse()方法及实例

StringBuilder的 reverse() 方法用于 逆转StringBuilder中的字符。 该方法有助于将该字符序列替换为该序列的反面。

语法

public java.lang.AbstractStringBuilder reverse()

返回： 该方法在反转字符后返回StringBuilder对象。下面的程序说明了java.lang.StringBuilder.reverse()方法：

示例1 :

// Java program to demonstrate
// the reverse() Method.
 
class GFG {
    public static void main(String[] args)
    {
 
        // create a StringBuilder object
        // with a String pass as parameter
        StringBuilder str
            = new StringBuilder("WelcomeGeeks");
 
        // print string
        System.out.println("String = "
                           + str.toString());
 
        // reverse the string
        StringBuilder reverseStr = str.reverse();
 
        // print string
        System.out.println("Reverse String = "
                           + reverseStr.toString());
    }
}

输出

String = WelcomeGeeks
Reverse String = skeeGemocleW

例2 :

// Java program to demonstrate
// the reverse() Method.
 
class GFG {
    public static void main(String[] args)
    {
 
        // create a StringBuilder object
        // with a String pass as parameter
        StringBuilder str
            = new StringBuilder("AAAABBBCCCC");
 
        // print string
        System.out.println("String = "
                           + str.toString());
 
        // reverse the string
        StringBuilder reverseStr = str.reverse();
 
        // print string
        System.out.println("Reverse String = "
                           + reverseStr.toString());
    }
}

输出

String = AAAABBBCCCC
Reverse String = CCCCBBBAAAA

参考文献： https://docs.oracle.com/javase/10/docs/api/java/lang/StringBuilder.html#reverse()