Java中Collection扩展之commons

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以下是部分代码：

package tk.zhangwei.commons;import java.util.ArrayList;import java.util.List;import org.apache.commons.collections4.Predicate;import org.apache.commons.collections4.PredicateUtils;import org.apache.commons.collections4.functors.EqualPredicate;import org.apache.commons.collections4.functors.NotNullPredicate;import org.apache.commons.collections4.functors.UniquePredicate;import org.apache.commons.collections4.iterators.UniqueFilterIterator;import org.apache.commons.collections4.list.PredicatedList;/*** * 相等，非空判断 * @author zw * */public class Demo01 {    public static void main(String[] args) {        System.out.println("*************非空判断*************");        Predicate notNull =  NotNullPredicate.notNullPredicate();        String str = "zz";        System.out.println(notNull.evaluate(str));//非空为true         System.out.println("*************相等判断*************");        Predicate<String> pre = EqualPredicate.equalPredicate("zhangwei");        boolean boo = pre.evaluate("zhangwei");        System.out.println(boo);        System.out.println("*************唯一性判断*************");        Predicate<Long> uniquePre = UniquePredicate.uniquePredicate();        List<Long> list = PredicatedList.predicatedList(new ArrayList<Long>(), uniquePre);        list.add(100L);        list.add(200L);        //list.add(100L);//出现重复值   抛出异常        System.out.println("*************自定义性判断*************");        Predicate<String> self =new Predicate<String>() {            //自定义判别式            @Override            public boolean evaluate(String obj) {                return obj.length()>5&&obj.length()<20;            }        };        Predicate notNull1 =  NotNullPredicate.notNullPredicate();        Predicate all =PredicateUtils.allPredicate(self,notNull1);//谁在前面就先判断谁        List list1 = PredicatedList.predicatedList(new ArrayList(), all);        list1.add("zhangwei");        //list1.add(null);        //list1.add("zw");    }}

package tk.zhangwei.commons;import java.util.ArrayList;import java.util.Collection;import java.util.Iterator;import java.util.List;import java.util.function.Predicate;import org.apache.commons.collections4.Closure;import org.apache.commons.collections4.CollectionUtils;import org.apache.commons.collections4.functors.IfClosure;/*** * 函数式编程，Closure 闭包 封装特定的业务 *  * @author zw * */public class Demo02 {    public static void main(String[] args) {        ifClosure();    }    /***     * 2选1,如果是打折商品，打9折。如果不是打折商品，满100减去20     */    public static void ifClosure(){        List<Goods> list1 = new ArrayList<Goods>();        list1.add(new Goods("2017夏装新款韩版宽松原宿bf风半袖情侣款ulzzang男士短袖T恤潮流", 19.9, true));        list1.add(new Goods("情侣装夏装2017新款韩版潮流个性创意简约上衣一男女短袖服装短轴", 145, false));        list1.add(new Goods("2017夏装新款韩版修身纯棉CK36情侣装短袖T恤女男装短款打底衫潮", 336, false));        //满百减20        Closure<Goods> cre = new Closure<Goods>(){            @Override            public void execute(Goods goods) {                if(goods.getPrice()>100){                goods.setPrice(goods.getPrice()-20);                }                }};        //打9折            Closure<Goods> count = new Closure<Goods>(){                @Override                public void execute(Goods goods) {                    if(goods.isDiscount()){                    goods.setPrice(goods.getPrice()*0.9);                    }                    }};            //判断            Predicate<Goods> pre =new Predicate<Goods>() {                @Override                public boolean test(Goods t) {                    return t.isDiscount();                }            };            //二选一        //  Closure<Goods> ifclo = IfClosure.ifClosure(pre, count, cre);            //  CollectionUtils.forAllDo(list1, ifclo);            //查看操作后的数据            for(Goods temp:list1){                System.out.println(temp);            }    }    /***     * 基本操作     */    public static void basic(){        // 数据        List<Employee> list = new ArrayList<Employee>();        list.add(new Employee("张伟", 12000));        list.add(new Employee("老王", 10000));        // 业务功能        Closure<Employee> cols = new Closure<Employee>() {            @Override            public void execute(Employee emp) {                emp.setSalary(emp.getSalary() * 1.2);            }        };        CollectionUtils.forAllDo(list, cols);        //操作后的数据        Iterator<Employee> teremp = list.iterator();        while (teremp.hasNext()) {            Employee emp = teremp.next();            String name = emp.getName();            double salay = emp.getSalary();            System.out.println(name+"---"+salay);        }    }}

package tk.zhangwei.commons;import java.util.Collection;import java.util.HashSet;import java.util.Set;import org.apache.commons.collections4.CollectionUtils;public class Demo03 {    public static void main(String[] args) {        Set<Integer> set = new HashSet<Integer>();        set.add(1);        set.add(2);        set.add(3);        Set<Integer> set1 = new HashSet<Integer>();        set1.add(2);        set1.add(3);        set1.add(5);        //并集        System.out.println("*************并集**************");        Collection<Integer> coll = CollectionUtils.union(set, set1);        for(Integer integer:coll){            System.out.println(integer);        }        //交集        System.out.println("*************交集**************");        coll=CollectionUtils.intersection(set, set1);        for(Integer integer:coll){            System.out.println(integer);        }        //差集        System.out.println("*************差集**************");        coll=CollectionUtils.subtract(set,set1);        for(Integer integer:coll){            System.out.println(integer);        }    }}

package tk.zhangwei.commons;import java.util.Queue;import java.util.function.Predicate;import org.apache.commons.collections4.Unmodifiable;import org.apache.commons.collections4.functors.NotNullPredicate;import org.apache.commons.collections4.queue.CircularFifoQueue;import org.apache.commons.collections4.queue.PredicatedQueue;import org.apache.commons.collections4.queue.UnmodifiableQueue;/*** * Queue队列 * 1.循环队列 * @author zw * */public class Demo04 {    public static void main(String[] args){        readOnly();    }    /***     * 断言队列     */    public static void predicate(){        CircularFifoQueue<String> que = new CircularFifoQueue<String>(2);        que.add("a");        que.add("b");        que.add("c");            }    /**     * 只读序列     */    public static void readOnly(){        CircularFifoQueue<String> que = new CircularFifoQueue<String>(2);        que.add("a");        que.add("b");        que.add("c");        Queue<String> readOnly =UnmodifiableQueue.unmodifiableQueue(que);        readOnly.add("a");    }    /***     *      * 循环队列     */    public static void circular(){        //循环队列        CircularFifoQueue<String> que = new CircularFifoQueue<String>(2);        que.add("a");        que.add("b");        que.add("c");        //查看        for(String temp:que){            System.out.println(temp);        }    }}

package tk.zhangwei.commons;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import org.apache.commons.collections4.IterableMap;import org.apache.commons.collections4.MapIterator;import org.apache.commons.collections4.iterators.ArrayIterator;import org.apache.commons.collections4.iterators.LoopingIterator;import org.apache.commons.collections4.iterators.UniqueFilterIterator;import org.apache.commons.collections4.map.HashedMap;/*** * 迭代器的扩展 * @author zw * */public class Demo05 {    public static void main(String[] args) {        arrayList();    }    /***     * 数组迭代     */    public static void arrayList(){        int[] a ={1,2,3,4,5};        //数组迭代器        //Iterator<Integer> it = new ArrayIterator<Integer>(a);        //指定起始索引和结束索引        Iterator<Integer> it = new ArrayIterator<Integer>(a,1,3);        while(it.hasNext()){            System.out.println(it.next());        }    }    /***     * 循环迭代器     */    public static void loopIt(){        List<String> list =new ArrayList<String>();        list.add("张伟");        list.add("老王");        list.add("王麻子");        Iterator<String> it = new LoopingIterator<String>(list);        for(int i=0;i<10;i++){            System.out.println(it.next());        }    }    /***      * 去重迭代器     */    public static void uniqueIt(){        List<String> list =new ArrayList<String>();        list.add("a");        list.add("b");        list.add("a");        Iterator<String> it = new UniqueFilterIterator<String>(list.iterator());        while(it.hasNext()){            String str = it.next();            System.out.println(str);        }    }    /***      * map迭代器     */    public static void mapIt(){        IterableMap<String, String> map = new HashedMap<String,String>();        map.put("a", "i love you");        map.put("b", "i hate you");        map.put("c", "i miss you");        MapIterator<String, String> it = map.mapIterator();        while(it.hasNext()){            String key = it.next();//这是移动游标            String value = it.getValue();            System.out.println(key+"--->"+value);        }    }}

package tk.zhangwei.commons;import org.apache.commons.collections4.BidiMap;import org.apache.commons.collections4.MapIterator;import org.apache.commons.collections4.bidimap.DualHashBidiMap;import org.apache.commons.collections4.bidimap.DualTreeBidiMap;/*** *  * 双向Map： 要求键与值不能重复 * @author zw * */public class Demo06 {    public static void main(String[] args) {        treeMap();    }    /***     * 有序的双向Map     */    public static void treeMap(){        BidiMap<String, Long> map = new DualTreeBidiMap<String,Long>();        map.put("张伟",17711111111L);        map.put("老王",18814568536L);        map.put("王麻子",15502912005L);        //反转遍历输出        MapIterator<Long, String> it =map.inverseBidiMap().mapIterator();        while(it.hasNext()){            Long key = it.next();            String value = it.getValue();            System.out.println(key+"--->"+value);        }    }    /***     * 无序的双向Map     */    public static void hashMap(){        BidiMap<String, Long> map = new DualHashBidiMap<String,Long>();        map.put("张伟",17711111111L);        map.put("老王",18814568536L);        map.put("王麻子",15502912005L);        System.out.println(map.inverseBidiMap().get(15502912005L));        //反转遍历输出        MapIterator<Long, String> it =map.inverseBidiMap().mapIterator();        while(it.hasNext()){            Long key = it.next();            String value = it.getValue();            System.out.println(key+"--->"+value);        }    }}

package tk.zhangwei.commons;import java.util.Iterator;import java.util.Set;import org.apache.commons.collections4.Bag;import org.apache.commons.collections4.bag.HashBag;import org.apache.commons.collections4.bag.TreeBag;/*** * BAG包允许重复 * HashBag  无序 * TreeBag  有序 * @author zw * */public class Demo07 {    public static void main(String[] args){        // 统计单词出现的次数        String[] arr = "I love you not for who you are, but for who I am before you".split(" ");        Bag<String> bag = new TreeBag<String>();        for (String temp : arr) {            bag.add(temp);        }        Set<String> keys = bag.uniqueSet();        for (String letters : keys) {            System.out.println(letters + "--->" + bag.getCount(letters));        }    }    /***     * 有序     */    public static void treeBag(){        Bag<Integer> bag = new TreeBag<Integer>();        bag.add(520);        bag.add(520, 5);// 增加520 5次        bag.remove(520, 1);// 移除520一次        bag.add(1314);        bag.add(521);        Iterator<Integer> it = bag.iterator();        while (it.hasNext()) {            System.out.println(it.next());        }    }    /***     * 无序     */    public static void hashBag(){        Bag<Integer> bag = new HashBag<Integer>();        bag.add(520);        bag.add(520,5);//增加520 5次        bag.remove(520,1);//移除520一次        bag.add(1314);        bag.add(521);        Iterator<Integer> it =bag.iterator();        while(it.hasNext()){            System.out.println(it.next());        }    }}

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