{"id":14142,"date":"2014-09-04T15:04:16","date_gmt":"2014-09-04T12:04:16","guid":{"rendered":"http:\/\/examples.javacodegeeks.com\/?p=14142"},"modified":"2019-03-21T12:49:35","modified_gmt":"2019-03-21T10:49:35","slug":"junit-runwith-example","status":"publish","type":"post","link":"https:\/\/examples.javacodegeeks.com\/java-development\/core-java\/junit\/junit-runwith-example\/","title":{"rendered":"JUnit RunWith Example"},"content":{"rendered":"

In this example we are going to explain how to run simultaneously more than one test cases using JUnit<\/code><\/a> testing framework and Eclipse IDE. This collection of different test cases that will be executed all together is otherwise called JUnit test suite and for this purpose we use the @RunWith<\/code> and @Suite<\/code> annotations.<\/p>\n

1. Create the java class to be tested<\/strong><\/h2>\n

Open Eclipse IDE and create a new project called JunitRunWithExample<\/code>. Create a new package called com.javacodegeeks.junit.suite<\/code> and then, create a java class named FirstDayAtSchool.java<\/code>, which will be the class to be tested. Below is the code of the class FirstDayAtSchool.java<\/code>.<\/p>\n

 
\nFirstDayAtSchool.java<\/em><\/span><\/p>\n

package com.javacodegeeks.junit.suite;\n\nimport java.util.Arrays;\n\npublic class FirstDayAtSchool {\n\tpublic String[] prepareMyBag() {\n\t\tString[] schoolbag = { \"Books\", \"Notebooks\", \"Pens\" };\n\t\tSystem.out.println(\"My school bag contains: \"\n\t\t\t\t+ Arrays.toString(schoolbag));\n\t\treturn schoolbag;\n\t}\n\n\tpublic String[] addPencils() {\n\t\tString[] schoolbag = { \"Books\", \"Notebooks\", \"Pens\", \"Pencils\" };\n\t\tSystem.out.println(\"Now my school bag contains: \"\n\t\t\t\t+ Arrays.toString(schoolbag));\n\t\treturn schoolbag;\n\t}\n}\n<\/pre>\n
As we can observe in the above class, there are two methods, prepareMyBag()<\/code> and addPencils()<\/code>, that they are just printing out the content of an array of strings.<\/p>\n
2. Create JUnit tests<\/strong><\/h2>\n
In this section, we will create the test cases for the above class. Before you create the test class, it is considered as good practice to create a new source folder dedicated to tests. For this purpose, right-click your project, select New -> Source Folder<\/em>, name the new source folder test<\/code> and click Finish<\/em>.<\/p>\n
\"Create<\/a>
Figure 1: Create new source folder for junit tests.<\/figcaption><\/figure><\/p>\n
You can also have the same result by right-clicking on your project and select Properties -> Java Build Path -> Source<\/em> and Add Folder<\/em>. You can see the result in the figure below:<\/p>\n
\"Figure<\/a>
Figure 2<\/figcaption><\/figure>
 
<\/div> <\/div><\/p>\n
Now we are ready to proceed with the creation of the JUnit test classes.
\nRight-click on the class that we want to test, in this case the class named FirstDayAtSchool.java<\/code> and select New \u2192 JUnit Test Case<\/em>.<\/p>\n
In the following wizard select the New JUnit 4 test flag and select the test source folder, so that your test class will be created in this folder.<\/p>\n
\"Figure<\/a>
Figure 3: Create a new junit test class.<\/figcaption><\/figure><\/p>\n
If your project does not contain the JUnit library in its classpath, the following message will be displayed so as to add the JUnit library to the classpath.<\/p>\n
\"Figure<\/a>
Figure 4: Add JUnit library to the classpath.<\/figcaption><\/figure><\/p>\n
Also, we would like to test only the first method of this class in this specific test, so we can select Next<\/em> in the wizard and choose the method prepareMyBag()<\/code>.<\/p>\n
\"Figure<\/a>
Figure 5: Select methods for which test method stubs will be created.<\/figcaption><\/figure><\/p>\n
The code of the first test class which is named FirstDayAtSchoolTest.java<\/code>, follows.<\/p>\n
FirstDayAtSchoolTest.java<\/em><\/span><\/p>\n
package com.javacodegeeks.junit.suite;\n\nimport static org.junit.Assert.*;\n\nimport org.junit.Test;\n\npublic class FirstDayAtSchoolTest {\n\n\tFirstDayAtSchool school = new FirstDayAtSchool();\n\tString[] bag = { \"Books\", \"Notebooks\", \"Pens\" };\n\n\t@Test\n\tpublic void testPrepareMyBag() {\n\t\tSystem.out.println(\"Inside testPrepareMyBag()\");\n\t\tassertArrayEquals(bag, school.prepareMyBag());\n\t}\n\n}\n<\/pre>\n
Following the same procedure, we create another test case for the class FirstDayAtSchool.java<\/code> which is called FirstDayAtSchoolTest2.java<\/code> and tests the second method of the class named addPencils()<\/code>.[ulp id=’ODQaBEw1BIbHApZq’]<\/p>\n
FirstDayAtSchoolTest2.java<\/em><\/span><\/p>\n
package com.javacodegeeks.junit.suite;\n\nimport static org.junit.Assert.*;\n\nimport org.junit.Test;\n\npublic class FirstDayAtSchoolTest2 {\n\n\tFirstDayAtSchool school = new FirstDayAtSchool();\n\tString[] bag = { \"Books\", \"Notebooks\", \"Pens\", \"Pencils\" };\n\n\t@Test\n\tpublic void testAddPencils() {\n\t\tSystem.out.println(\"Inside testAddPencils()\");\n\t\tassertArrayEquals(bag, school.addPencils());\n\t}\n\n}\n<\/pre>\n
3. Create test suite using annotation @RunWith<\/strong><\/h2>\n
Now, we are going to create the test suite class. Right-click on the test source folder and select New -> Other -> JUnit -> JUnit Test Suite<\/em>. Then, choose the name of the suite and the test classes that will be included in the suite and click Finish<\/em>.<\/p>\n
\"Figure<\/a>
Figure 6: Create a test suite.<\/figcaption><\/figure><\/p>\n
The class following is the test suite of the two test classes.<\/p>\n
AllTests.java<\/em><\/span><\/p>\n
package com.javacodegeeks.junit.suite;\n\nimport org.junit.runner.RunWith;\nimport org.junit.runners.Suite;\nimport org.junit.runners.Suite.SuiteClasses;\n\n@RunWith(Suite.class)\n@SuiteClasses({ FirstDayAtSchoolTest.class, FirstDayAtSchoolTest2.class })\npublic class AllTests {\n\n}\n<\/pre>\n
In the test suite, we can see that there are two annotations, @RunWith<\/code> and @SuiteClasses<\/code>.
\nLet’s give a short explanation of them.<\/p>\n