基于Java8 函数式接口理解及测试

@FunctionalInterface
　public interface AppleInterface {
public void test();
　}

java.util.function.Consumer;
java.util.function.Function;
java.util.function.Predicate;
java.util.function.Supplier;  

FunctionInterface interface=null;

public void filter(FunctionInterface interface)
{
　interface.doSomeThing();
}

public class Apple {
  private String color;
  private float weight;

  public Apple(String color, float weight) {
  this.color = color;
  this.weight = weight;
  }

  public String getColor() {
  return color;
  }

  public void setColor(String color) {
  this.color = color;
  }

  public float getWeight() {
  return weight;
  }

  public void setWeight(float weight) {
  this.weight = weight;
  }
}

@FunctionalInterface
public interface AppleInterface {
  public void test();
}

 @Test
  public void DefineFunctionInterface(){
  //自定义函数式接口
  AppleInterface at=()->System.out.println("define FunctionInterface AppleInterface.");
  at.test();
  }

 @Test
  public void ConsumerTest(){
  Consumer<Apple> consumer=(Apple app)->{System.out.println(app.getColor()+","+app.getWeight());};
  List<Apple> apps=Arrays.asList(new Apple("red", 120),new Apple("blue", 80),
 new Apple("green",100));
  ConsumerApple(apps,consumer);
  }

  public void ConsumerApple(List<Apple> apps,Consumer<Apple> c){
  for(Apple app:apps){
 c.accept(app);
  }
  }

 @Test
  public void SupplierTest(){
  Supplier<Apple> supplier=()->{return new Apple("hello supplier",999);};
  Apple app=supplier.get();
  System.out.println(app.getColor()+","+app.getWeight());
  }

 @Test
  public void PredicateTest(){
  //系统预定义函数式接口测试
  Predicate<Apple> p1=(Apple a)->{if(a.getWeight()>90) return true;return false;};
  Predicate<Apple> p2=(Apple a)->{if(a.getColor().equals("blue")) return true;return false;};

  List<Apple> apps=Arrays.asList(new Apple("red", 120),new Apple("blue", 80),
 new Apple("green",100));

  filterApple(apps,p1);//筛选重量大于90g的苹果
  filterApple(apps,p2);//筛选蓝色的苹果
  }

  public void filterApple(List<Apple> apps,Predicate<Apple> p){
  for(Apple app:apps){
 if(p.test(app)){
 System.out.println(app.getColor()+","+app.getWeight());
 }
  }

  } 

 @Test
  public void FunctionTest(){
  Function<String,Apple> function=(String s)->{return new Apple(s,666);};
  Apple app=function.apply("red");
  System.out.println(app.getColor()+","+app.getWeight());
  app=function.apply("green");
  System.out.println(app.getColor()+","+app.getWeight());

  }