Question

我试图通过在System.out.println()内定义静态方法来缩短Util.java。我想利用Util.print（）进一步缩短为print()。所以我做了静态导入。

Util.java与ListOfNumbers.java位于同一目录下。当我尝试从测试器类访问writeList（）时，我得到以下错误：

import java.io.*;
import java.util.List;
import java.util.ArrayList;
import static Util;

public class ListOfNumbers {
    ...
    ...
    public void writeList() {
    // The FileWriter constructor throws IOException, which must be caught.
        PrintWriter out = null;

        try {
            print("Entered try statement...");
            ...
        } catch (IOException | IndexOutOfBoundsException e){            
            print("Exception thrown: \n" + e.getMessage());
            ...
        }
    }
}

错误：

>> javac Tester.java && java Tester
.\ListOfNumbers.java:4: error: '.' expected
import static Util;
                  ^
.\ListOfNumbers.java:4: error: ';' expected
import static Util;
                   ^
.\ListOfNumbers.java:4: error: cannot find symbol
import static Util;
              ^
  symbol: class Util
.\ListOfNumbers.java:4: error: static import only from classes and interfaces
import static Util;
^
.\ListOfNumbers.java:24: error: cannot find symbol
                        print("Entered try statement...");
                        ^
  symbol:   method print(String)
  location: class ListOfNumbers
.\ListOfNumbers.java:34: error: cannot find symbol
                        print("Exception thrown: \n" + e.getMessage());
                        ^
  symbol:   method print(String)
  location: class ListOfNumbers
6 errors

Answer 1

您应该导入方法名称

import static Util.print;

如果要从Util导入所有静态方法：

import static Util.*;

Answer 2

以下答案帮助我克服了这个问题！猜猜这一定是个bug。

Java static member from default package cannot be imported!

从java中的默认包导入静态类时出错

2 个答案: