让开发效率爆表的Guava ---- FluentIterable迭代器

Guava提供了可以在Iterator中进行处理的功能更丰富的迭代器， 其实就像是加了一个代理， 增加一些功能。

package com.wenniuwuren.collections;

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

import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.Lists;

/**
 *
 * @author wenniuwuren
 *
 */
public class FluentIterableTest {

	@SuppressWarnings("unchecked")
	public static void main(String[] args) {
		Person person1 = new Person("lilei", 50);
		Person person2 = new Person("hanmeimei", 40);
		@SuppressWarnings("rawtypes")
		ArrayList personList = Lists.newArrayList(person1, person2);

		//返回一个按条件过滤后的结果集
		Iterable<Person> personFilterByAge = FluentIterable.from(personList)
				  .filter(new Predicate<Person>() {

					@Override
					public boolean apply(Person input) {

						return input.getAge() > 40;
					}

				  });
		Iterator<Person> i = personFilterByAge.iterator();
		while(i.hasNext()) {
			System.out.println("年龄大于40的是：" + i.next().getName());
		}

		System.out.println("-------------我是邪恶的分割线-------------");

		// 返回处理过的结果集
		List<String> transformedPersonList = FluentIterable.from(personList)
				.transform(new Function<Person, String>() {
					@Override
					public String apply(Person input) {
						return Joiner.on(':').join(input.getName(), input.getAge());
					}

				}).toList();
	   Iterator transformedPersonListIterator = transformedPersonList.iterator();
	   while(transformedPersonListIterator.hasNext()) {
		   System.out.println("拼接起来的结果是：" + transformedPersonListIterator.next());
	   }

	 }

}

class Person {
	private String name;
	private int age;

	public Person(String name, int age) {
		this.name = name;
		this.age = age;
	}

	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
}

参考资料：

《Getting Started with Google Guava》