package com.liang.lambda;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Predicate;
/**
* @ClassName Java8Lambda
* @description java8 lambda 表达式
* @Author https://www.cnblogs.com/anakin/p/7742779.html
* @Date 2018/12/4
*/
public class Java8Lambda {
public static void main(String[] args) {
Java8Lambda lambda = new Java8Lambda();
lambda.mapEach();
}
public void newThread() {
new Thread(() -> System.out.println("new thread start!")).start();
}
public void forList() {
List list = Arrays.asList("a", "b", "c", "d");
list.forEach(n -> {
System.out.printf("====%s====\n",n);
System.out.println(n);
});
System.out.println("-------------------");
list.forEach(System.out::println);
}
public void predicateAnd() {
Predicate startsWithJ = (n) -> n.startsWith("J");
Predicate fourLetterLong = (n) -> n.length() == 4;
List names = Arrays.asList("Java", "Scala", "C++", "Haskell", "Lisp");
names.stream()
.filter(startsWithJ.and(fourLetterLong))
.forEach((n) -> System.out.println("Name, which starts with'J' and four letter long is : " + n));
}
public void mapReduce() {
List costBeforeTax = Arrays.asList(100, 200, 300, 400, 500);
costBeforeTax.stream().map((cost) -> cost + 0.12 * cost)
.forEach(System.out::println);
}
public void mapEach(){
Map map = new HashMap<>();
map.put("1","a");
map.put("2","b");
map.forEach((k, v) -> System.out.println("key:value = " + k + ":" + v));
}
}