java全排列通用工具类，java通用工具类,全排列处理接口

java全排列通用工具类，java通用工具类,全排列处理接口

全排列处理接口 ```javapublic interface PermutationProcessor<T> { void process(T[]array);}

全排列类javapublic final class FullPermutation {

public  static <T> void permutate(T a[], PermutationProcessor<T> processor) {    permutate(a, 0, a.length,processor);}

static <T> void permutate(T a[], int m, int n,PermutationProcessor<T> processor) { int i; T t; if (m < n - 1) { permutate(a, m + 1, n,processor); for (i = m + 1; i < n; i++) { swap(a, m, i); permutate(a, m + 1, n,processor); swap(a, m, i); } } else { processor.process(a); } }

private static <T> void swap(T[] a, int m, int i) {    T t;    t = a[m];    a[m] = a[i];    a[i] = t;}

}[代码]调用示例java public static void main(String[] args) { Integer[] a={1,2,4}; FullPermutation.permutate(a, new PermutationProcessor<Integer>() { @Override public void process(Integer[] array) { for(int i:array){ System.out.printf("%d ",i); } System.out.println(); } }); }

[代码]运行结果text1 2 4 1 4 2 2 1 4 2 4 1 4 2 1 4 1 2 ```