Apache common collection的使用（2）

Closure 的使用

全部执行：把所有员工都执行salaryClosure操作

条件循环执行：循环执行salaryClosure，直到满足predicate则停止循环（类似复利的计算）

Closure<Employee>  whileCol = WhileClosure.whileClosure(predicate, salaryClosure, false);
           

二选一执行：满足predicate的条件，则执行discount，否则执行subtract（如果满足打折的情况，则进行打折操作，如果不满足打折，则看是否可以减免）

Closure<Goods> ifClosure = IfClosure.ifClosure(predicate,discount, subtract);
           

顺序实行：先执行discount，再执行subtract（折上折：先打折再减免）

package cn.others;

import org.apache.commons.collections4.Closure;
import org.apache.commons.collections4.IteratorUtils;
import org.apache.commons.collections4.Predicate;
import org.apache.commons.collections4.functors.WhileClosure;

import java.util.ArrayList;
import java.util.List;

/**
 * @author Duoduo
 * @version 1.0
 * @date 2017/4/15 13:27
 */
public class Test4 {
    public static void main(String[] args) {

        List<Employee> employees = new ArrayList<Employee>();
        employees.add(new Employee("employee1", ));
        employees.add(new Employee("employee2", ));
        employees.add(new Employee("employee3", ));
        employees.add(new Employee("employee4", ));

        Closure<Employee> salaryClosure = new Closure<Employee>() {
            public void execute(Employee employee) {
                employee.setSalary(employee.getSalary() * );
            }
        };
        //把所有的Employee都执行加薪操作
        IteratorUtils.forEach(employees.iterator(), salaryClosure);

        System.out.println("=========== 执行所有人都加薪之后的结果 ==============");
        for (Employee employee : employees) {
            System.out.println(employee);
        }



        Predicate<Employee> predicate = new Predicate<Employee>() {
            public boolean evaluate(Employee employee) {
                return employee.getSalary() < ;
            }
        };

        //会一直按照百分百循环，直到满足谓词的判断条件
        Closure<Employee>  whileCol = WhileClosure.whileClosure(predicate, salaryClosure, false);
        IteratorUtils.forEach(employees.iterator(), whileCol);

        System.out.println("=========== 满足特定的条件一直循环执行的结果 ==============");
        for (Employee employee : employees) {
            System.out.println(employee);
        }

    }

}
           

执行结果

=========== 执行所有人都加薪之后的结果 ==============

Employee{name=’employee1’, salary=150.0}

Employee{name=’employee2’, salary=300.0}

Employee{name=’employee3’, salary=450.0}

Employee{name=’employee4’, salary=600.0}

=========== 满足特定的条件一直循环执行的结果 ==============

Employee{name=’employee1’, salary=225.0}

Employee{name=’employee2’, salary=300.0}

Employee{name=’employee3’, salary=450.0}

Employee{name=’employee4’, salary=600.0}

package cn.others;

import org.apache.commons.collections4.Closure;
import org.apache.commons.collections4.IteratorUtils;
import org.apache.commons.collections4.Predicate;
import org.apache.commons.collections4.functors.ChainedClosure;
import org.apache.commons.collections4.functors.IfClosure;

import java.util.ArrayList;
import java.util.List;

/**
 * @author Duoduo
 * @version 1.0
 * @date 2017/4/15 13:45
 */
public class Test5 {

    public static void main(String[] args){
        List<Goods> goodss = new ArrayList<Goods>();
        goodss.add(new Goods("goods1",, true));
        goodss.add(new Goods("goods2",, false));
        goodss.add(new Goods("goods3",, true));

        System.out.println("************ 原始数据 ****************");
        for (Goods goods : goodss){
            System.out.println(goods);
        }

        //减价20
        Closure<Goods> subtract = new Closure<Goods>() {
            public void execute(Goods input) {
                input.setPrice(input.getPrice()-);
            }
        };

        //商品打折
        Closure<Goods> discount = new Closure<Goods>() {
            public void execute(Goods input) {
                input.setPrice(input.getPrice()*);
            }
        };

        //判读是否打折
        Predicate<Goods> predicate = new Predicate<Goods>() {
            public boolean evaluate(Goods goods) {
                return goods.isDiscount();
            }
        };

        //判断条件，如果满足谓词，则先执行打折，如果不满足，则执行扣减
        Closure<Goods> ifClosure = IfClosure.ifClosure(predicate,discount, subtract);
        IteratorUtils.forEach(goodss.iterator(),ifClosure);
        System.out.println("************ 二选一执行结果 ****************");
        for (Goods goods : goodss){
            System.out.println(goods);
        }

        //先打折，再减免
        Closure<Goods> chainColsure = ChainedClosure.chainedClosure(discount, subtract);
        IteratorUtils.forEach(goodss.iterator(), chainColsure);
        System.out.println("************ 折上折执行结果 ****************");
        for (Goods goods : goodss){
            System.out.println(goods);
        }




    }
}
           

执行结果

** 原始数据 ******

Goods{name=’goods1’, price=100.0, discount=true}

Goods{name=’goods2’, price=200.0, discount=false}

Goods{name=’goods3’, price=300.0, discount=true}

** 二选一执行结果 ******

Goods{name=’goods1’, price=90.0, discount=true}

Goods{name=’goods2’, price=180.0, discount=false}

Goods{name=’goods3’, price=270.0, discount=true}

** 折上折执行结果 ******

Goods{name=’goods1’, price=61.0, discount=true}

Goods{name=’goods2’, price=142.0, discount=false}

Goods{name=’goods3’, price=223.0, discount=true}