package com.bsc.algorithm.data.generator;

import java.lang.reflect.Array;
import java.util.Random;

/**
 * 數組生成器
 * @author bsc
 *
 */
public class ArrayGenerator {

    /**
     * 隨機生成size大小的數組
     * @param arrayClass 數組class，例如Integer[].class,int[].class,Character[].class,char[].class
     * @param
 
 size 數組大小
     * @param min 最小值
     * @param max 最大值
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> T random(Class<T> arrayClass, int size,int min,int max) {
        int diff = max - min + 1;
        Random random = new Random();
        Class<?> componentType = arrayClass.getComponentType();
        String componentName 
 
= componentType.getName();
        T array = (T) Array.newInstance(componentType, size);
        
        if("char".equals(componentName) || Character.class.getName().equals(componentName)) {
            for (int i = 0; i < size; i++) {
                Array.set(array, i, (char)(random.nextInt(diff) + min));
            }
        }
 
else {
            for (int i = 0; i < size; i++) {
                Array.set(array, i, random.nextInt(diff) + min);
            }
        }
        return array;
    }
    
    /**
     * 生成指定序列數組
     * @param arrayClass 數組class，例如Integer[].class,int[].class,Character[].class,char[].class
     * @param size 數組大小
     * @param start 數組開始值
     * @param increment 數組元素間增量
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> T seq(Class<T> arrayClass, int size,int start,int increment) {
        Class<?> componentType = arrayClass.getComponentType();
        String componentName = componentType.getName();
        T array = (T) Array.newInstance(componentType, size);
        
        if("char".equals(componentName) || Character.class.getName().equals(componentName)) {
            for (int i = 0; i < size; i++) {
                Array.set(array, i, (char)(start));
                start += increment;
            }
        }else {
            for (int i = 0; i < size; i++) {
                Array.set(array, i, start);
                start += increment;
            }
        }
        return array;
    }

    public static void main(String[] args) {
        int[] dataInt = ArrayGenerator.random(int[].class, 20,10,99);
        System.out.print("random:\t");
        for (int i = 0; i < dataInt.length; i++) {
            System.out.print(dataInt[i] + " ");
        }
        System.out.println();
        System.out.print("   seq:\t");
        dataInt = ArrayGenerator.seq(int[].class, 20,20,1);
        for (int i = 0; i < dataInt.length; i++) {
            System.out.print(dataInt[i] + " ");
        }
        System.out.println();
        System.out.print("random:\t");
        char[] dataChar = ArrayGenerator.random(char[].class, 26,65,90);
        for (int i = 0; i < dataChar.length; i++) {
            System.out.print(dataChar[i] + " ");
        }
        System.out.println();
        System.out.print("   seq:\t");
        dataChar = ArrayGenerator.seq(char[].class, 26,65,1);
        for (int i = 0; i < dataChar.length; i++) {
            System.out.print(dataChar[i] + " ");
        }
    }
}

數組數據生成器