Question

我是Java的新手，现在正在学习The Java Tutorials。当我在LabmdaScopeTest.java中输入确切的代码时，我遇到了错误package java.util.funciton does not exist。代码如下。

import java.util.funciton.Consumer;

public class LambdaScopeTest {

public int x = 0;

class FirstLevel {

    public int x = 1;

    void methodInFirstLevel(int x) {

        // The following statement causes the complier to generate
        // the error "local variables referenced from a lambda expression
        // must be final or effectively final" in statemen A:
        //
        // x = 99;

        Consumer<Integer> myConsumer = (y) ->
        {
            System.out.println("x = " + x); // statement A
            System.out.println("y = " + y);
            System.out.println("this.x = " + this.x);
            System.out.println("LambdaScopeTest.this.x = " + 
                LambdaScopeTest.this.x);
        };

        myConsumer.accept(x);
    }
}

public static void main(String[] args) {
    LambdaScopeTest st = new LambdaScopeTest();
    LambdaScopeTest.FirstLevel fl = st.new FirstLevel();
    fl.methodInFirstLevel(23);
}

}

我对import语句进行了评论，并将代码替换为java.util.function.Consumer<Integer> myConsumer，一切正常。

Answer 1

你有一个错字：

import java.util.funciton.Consumer;
                     ↑↑

应该是：

import java.util.function.Consumer;

包java.util.function不存在？

1 个答案: