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

IteratorUtils.forEach(employees.iterator(), salaryClosure);

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）

Closure<Goods> chainColsure = ChainedClosure.chainedClosure(discount, subtract);

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", 100));        employees.add(new Employee("employee2", 200));        employees.add(new Employee("employee3", 300));        employees.add(new Employee("employee4", 400));        Closure<Employee> salaryClosure = new Closure<Employee>() {            public void execute(Employee employee) {                employee.setSalary(employee.getSalary() * 1.5);            }        };        //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() < 200;            }        };        //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",100, true));        goodss.add(new Goods("goods2",200, false));        goodss.add(new Goods("goods3",300, 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()-20);            }        };        //商品打折        Closure<Goods> discount = new Closure<Goods>() {            public void execute(Goods input) {                input.setPrice(input.getPrice()*0.9);            }        };        //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}