java - JUNIT 测试 - Eclipse IDE 抛出错误

Question

我有下面的类和方法，我试图让 JUNIT 测试工作，但它抛出了一个错误。这是类(class)

package christmas;

public class Worksheet1q1 {

    public static void main(String[] args) {
        int m = 3, n = 4;
        int result = power(m, n);
        System.out.printf( "power method  ");
        System.out.printf( "%d^%d = %d", m, n, result);


    } 

    //* code for  power

static int power(int m, int n) {



    if (n != 0)



        return (m * power(m, n - 1));
    else


 }}

这是我的 JUNIT 测试类和方法。

  package christmas;


  import static org.junit.Assert.assertThat;

  import org.junit.Test;



  public class Worksheet1q1Test {

    @Test


    public void twoAndThreeissix(int m, int n) throws Exception {




    int result = Worksheet1.power(2, 3);

    assertThat(result, is(8L));

    }}

我有 2 个问题。首先，当我运行 Test 类时，出现错误，方法“找不到 christmas”，但 christmas 是我的包名称，所以不确定为什么 Eclipse 认为它是一个方法

另外，我在assertThat 上收到错误 - 该错误表明无法找到“is”方法。

这是我第一次尝试 JUNIT 测试，因此我们将不胜感激。

Answer 1

我运行了你的代码，并在游戏开始时修复了错误。我在命令行上运行它。我已将所有出错的内容都放入注释中:

package christmas;

public class Worksheet1q1 {

    public static void main(String[] args) {
        int m = 3, n = 4;
        int result = power(m, n);
        System.out.printf( "power method  ");
        System.out.printf( "%d^%d = %d", m, n, result);
    } 

    //* code for  power
    static int power(int m, int n) {
      if (n != 0)
        return (m * power(m, n - 1));
      else return 1;    // added due to below error
    }                   // compile error, illegal start of statement.
}

对于测试，我添加了一个不会因 int 而不是 long 而失败的测试:

package christmas;

import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.hamcrest.CoreMatchers.is; //  error: cannot find symbol

// compiler: warning: [deprecation] <T>assertThat(T,Matcher<? super T>) in Assert has been deprecated
// import static org.junit.Assert.assertThat;
import static org.hamcrest.MatcherAssert.assertThat;

public class Worksheet1q1Test {

    @Test
    // FAILURES!!!  Method twoAndThreeIsEightLong should have no parameters
//    public void twoAndThreeIsEightLong(int m, int n) throws Exception {
    public void twoAndThreeIsEightLong() throws Exception {
//      int result = Worksheet1.power(2, 3); // error: cannot find symbol
      int result = Worksheet1q1.power(2, 3);
      assertThat(result, is(8L));  // result is an int - will fail!
    }

    @Test
    public void twoAndThreeIsEightInt() throws Exception {
      int result = Worksheet1q1.power(2, 3);
      assertThat(result, is(8));
    }

    @Test
    public void twoAndThreeIsEight() throws Exception {
      int result = Worksheet1q1.power(2, 3);
      assertEquals(result, 8);
    }
}

编译:

javac -cp C:\..snip..\lib\junit-4.13.jar;C:\..snip..\lib\hamcrest-core-1.3.jar;target -d target src/christmas/*.java

运行:

java -cp C:\..snip..\lib\junit-4.13.jar;C:\..snip..\lib\hamcrest-core-1.3.jar;target org.junit.runner.JUnitCore christmas.Worksheet1q1Test 

结果:

JUnit version 4.13
...E
Time: 0.042
There was 1 failure:
1) twoAndThreeIsEightLong(christmas.Worksheet1q1Test)
java.lang.AssertionError:
Expected: is <8L>
     but: was <8>
        at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:20)
        at org.junit.Assert.assertThat(Assert.java:964)
        at org.junit.Assert.assertThat(Assert.java:930)
        at christmas.Worksheet1q1Test.twoAndThreeIsEightLong(Worksheet1q1Test.java:18)

FAILURES!!!
Tests run: 3,  Failures: 1