java jdk1.8新特性Stream API( 三 ) _电脑

sm.forEach(System.out::println);
});

System.out.println("---------------------------");
Stream<Character> stream2 = list.stream().flatMap(TestStreamAPI3::filterCharacter);
stream2.forEach(System.out::println);
}

public static Stream<Character> filterCharacter(String str) {// add(Object obj) addAll(collection coll)
List<Character> list = new ArrayList<>();

for (Character character : str.toCharArray()) {
list.add(character);
}

return list.stream();
}
}

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44、Stream排序
package com.stream.api4;

import java.util.Arrays;
import java.util.List;

import org.junit.Test;

import com.stream.api1.Employee;

public class TestStreamAPI4 {

List<Employee> employees = Arrays.asList(new Employee("张三", 12, 1200.99), new Employee("小明", 15, 4500.99),
new Employee("小丽", 16, 5500.99), new Employee("王二", 32, 1100.99), new Employee("二虎", 22, 9825.99),
new Employee("李静", 18, 4502.99), new Employee("小三", 17, 1469.99), new Employee("小三", 17, 1469.99),
new Employee("小三", 17, 1469.99), new Employee("小三", 17, 1469.99));

/**
* 排序 sorted() —— 天然排序(Comparable) sorted(Comparater com) —— 定制排序(Comparater)
*/
@Test
public void test1() {

List<String> list = Arrays.asList("ccc", "aaa", "bbb", "ddd", "eee");

list.stream().sorted().forEach(System.out::println);

System.out.println("--------------------------------------------");

employees.stream().sorted((e1, e2) -> {
if (e1.getAge() == e2.getAge()) {
return e1.getName().compareTo(e2.getName());
} else {
return Integer.compare(e1.getAge(), e2.getAge());
}
}).forEach(System.out::println);

}

}

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55、Stream查找与匹配
package com.stream.api5;

import java.util.Arrays;
【java jdk1.8新特性Stream API】import java.util.List;
import java.util.Optional;

import org.junit.Test;

import com.stream.api1.Employee;
import com.stream.api1.Employee.Status;

public class TestStreamAPI5 {

List<Employee> employees = Arrays.asList(new Employee("张三", 12, 1200.99, Status.BUSY),
new Employee("小明", 15, 4500.99, Status.BUSY), new Employee("小丽", 16, 5500.99, Status.BUSY),
new Employee("王二", 32, 1100.99, Status.FREE), new Employee("二虎", 22, 9825.99, Status.FREE),
new Employee("李静", 18, 4502.99, Status.FREE), new Employee("小三", 17, 1469.99, Status.VOCATION),
new Employee("小三", 17, 1469.99, Status.VOCATION), new Employee("小三", 17, 1469.99, Status.VOCATION),
new Employee("小三", 17, 1469.99, Status.VOCATION));