java实现方法的联级调用

布满荆棘的人生 2022-11-07 01:50 191阅读 0赞

## 1.Stringlei中的方法都可以联级调用 ##

## 2.用return this这个语句,在网上查找到的,可以实现 ##

> 具体代码实现看下面

public class Nine {
        
        //九九乘法表左对齐
        public Nine printLeft(int num) {
        
            for (int i = 1; i < num + 1; i++) {
        
                for (int j = 1; j <= i; j++) {
        
                    System.out.print(j + "*" + i + "=" + i * j + "\t");
                }
                System.out.println();
            }
            return this;
        }
    
        //九九乘法表右对齐
        public Nine printRight(int num) {
        
            for (int i = 1; i <= num; i++) {
        
                //前面空num-i个
                for (int k = 1; k <= (num - i); k++) {
        
                    System.out.print("\t" + "\t");
                }
                for (int j = 1; j <= i; j++) {
        
                    System.out.print(j + "*" + i + "=" + i * j + "\t");
                }
                System.out.println();
            }
            return this;
        }
        //九九乘法表居中对齐
        public Nine printCenter(int num) {
        
            for (int i = 1; i < num + 1; i++) {
        
                //根据行数来选择前面空了几个
                for (int k = num; k > i; k--) {
        
                    System.out.print("\t");
                }
                for (int j = 1; j <= i; j++) {
        
                    System.out.print(j + "*" + i + "=" + i * j + "\t");
                }
                System.out.println();
            }
            return this;
        }
    }

**> 最后的调用如下,看下面的结果是可以实现的,虽然我不知道具体的原理**

public class L1_2Main {
        
        public static void main(String[] args) {
        
            int num = 8;
            Nine nine = new Nine();
            nine.printRight(num).printLeft(num).printCenter(num);
        }
    }