接口比较器

public class Study04 {
//定义一个方法为所有的类进行排序，前提是类必须熟悉comparable1接口
//运用多态，用接口类引用数组做形式参数，接收不同的实参数组
public static void sort(Comparable1[] comparable1s) {
for (int i = 1; i < comparable1s.length; i++) {//控制趟数
//每趟所作的操作，从第一个元素开始进行比较相邻的两个元素，如果符合排序条件，交换两个元素值
//每趟开始之前定义一个标记变量
boolean flag = true;
for (int j = 0; j < comparable1s.length - i; j++) {
//符合条件进行交换
if (comparable1s[j].compareTo(comparable1s[j + 1]) > 0) {
Comparable1 temp;
temp = comparable1s[j];
comparable1s[j] = comparable1s[j + 1];
comparable1s[j + 1] = temp;
flag = false;//如果发生交换，改变标记变量值

            }
        }
        if (flag) {
            break;

        }
    }
}

public static void main(String[] args) {
    /**
     * 接口内部比较器
     */
    Student001 st1 = new Student001("小黄", 2, 98);
    Student001 st2 = new Student001("小绿", 23, 98);
    Student001 st3 = new Student001("小冰", 1, 90);
    Student001 st4 = new Student001("小李", 32, 8);
    Student001 st5 = new Student001("小陈", 5, 28);
    Student001[] stt = {st1, st2, st3, st4, st5};
    System.out.println("遍历排序之前的数组=======");
    for (Student001 st : stt
    ) {
        System.out.println(st.toString());

    }
    sort(stt);
    //遍历排序之后的数组
    System.out.println("遍历排序之后的数组=======");
    for (Student001 st : stt
    ) {
        System.out.println(st.toString());
    }
}

}

interface Comparable1 {
//Object类型，可以传入若干子类型，多态用法；
public int compareTo(Object object);
}

//创建子类实现接口

class Student001 implements Comparable1 {

private String name;
private int id;
private double score;

//定义无参构造方法
public Student001() {

}

public Student001(String name, int id, double score) {
    super();
    this.name = name;
    this.id = id;
    this.score = score;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public double getScore() {
    return score;
}

public void setScore(double score) {
    this.score = score;
}

@Override
public String toString() {
    return "Student001{" +
            "name='" + name + '\'' +
            ", id=" + id +
            ", score=" + score +
            '}';
}

@Override
public int compareTo(Object object) {
    Student001 student001 = (Student001) object;
    int result = this.id - student001.id;
    return result;
}

}

外部比较器

public class Student05 {
public static void sort(Object[] objects, Comparator01 comparator01) {
for (int i = 1; i < objects.length; i++) {//控制趟数

        //每趟所作的操作，从第一个元素开始进行比较相邻的两个元素，如果符合排序条件，交换两个元素值
        //每趟开始之前定义一个标记变量
        boolean flag = true;
        for (int j = 0; j < objects.length - i; j++) {
            //符合条件进行交换
            if (comparator01.compare(objects[j], objects[j + 1]) > 0) {
                Object temp;
                temp = objects[j];
                objects[j] = objects[j + 1];
                objects[j + 1] = temp;
                flag = false;//如果发生交换，改变标记变量值

            }
        }
        if (flag) {
            break;

        }
    }
}

public static void main(String[] args) {
    /**
     * 接口内部比较器
     */
    Student002 st1 = new Student002("小黄", 2, 98);
    Student002 st2 = new Student002("小绿", 23, 98);
    Student002 st3 = new Student002("小冰", 1, 90);
    Student002 st4 = new Student002("小李", 32, 8);
    Student002 st5 = new Student002("小陈", 5, 28);
    Student002[] stt = {st1, st2, st3, st4, st5};
    //定义一个外部比较器对象
    StuIdComp stuIdComp = new StuIdComp();
    System.out.println("遍历排序之前的数组=======");
    for (Student002 st : stt
    ) {
        System.out.println(st.toString());

    }
    sort(stt, stuIdComp);
    //遍历排序之后的数组
    System.out.println("遍历排序之后的数组=======");
    for (Student002 st : stt
    ) {
        System.out.println(st.toString());
    }
}

}

//定义外部比较器
interface Comparator01 {
//形参是Object类型，用多态
public int compare(Object obj1, Object Obj2);
}

class StuIdComp implements Comparator01 {

@Override
public int compare(Object obj1, Object Obj2) {
    //强制类型转换
    Student002 st = (Student002) obj1;
    Student002 st01 = (Student002) Obj2;
    int result = st.getId() - st01.getId();
    return result;
}

}

//定义学生类
class Student002 {
private String name;
private int id;
private double score;

public Student002() {
}

public Student002(String name, int id, double score) {
    super();
    this.name = name;
    this.id = id;
    this.score = score;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public double getScore() {
    return score;
}

public void setScore(double score) {
    this.score = score;
}

@Override
public String toString() {
    return "Student002{" +
            "name='" + name + '\'' +
            ", id=" + id +
            ", score=" + score +
            '}';
}

}