深入理解java1.8之supplier

public class TestSupplier {
 private int age;
 
 TestSupplier(){
 System.out.println(age);
 }
 public static void main(String[] args) {
 //创建Supplier容器，声明为TestSupplier类型，此时并不会调用对象的构造方法，即不会创建对象
 Supplier<TestSupplier> sup= TestSupplier::new;
 System.out.println("--------");
 //调用get()方法，此时会调用对象的构造方法，即获得到真正对象
 sup.get();
 //每次get都会调用构造方法，即获取的对象不同
 sup.get();
 }
}

/**
 * Represents a supplier of results.
 *
 * <p>There is no requirement that a new or distinct result be returned each
 * time the supplier is invoked.
 *
 * <p>This is a <a href="package-summary.html" rel="external nofollow" >functional interface</a>
 * whose functional method is {@link #get()}.
 *
 * @param <T> the type of results supplied by this supplier
 *
 * @since 1.8
 */
@FunctionalInterface
public interface Supplier<T> {
 
  /**
   * Gets a result.
   *
   * @return a result
   */
  T get();
}

Supplier<TestSupplier> sup= TestSupplier::new;