JUnit testing using ContainsAll-assertion - mysql

Question

I'm testing a search function in the booking system I recently coded for my first semester project. My idea to test this was: I let the original search method return an arraylist of customers found in the search, fetch the list of all customers, and if the list of all customers contains the arraylist of customers found in the search, I assert that this works.
Note: I am prior creating a specific entry which I know I will find (hopefully, right?).
My problem is that when I call -
assertTrue(allCustomers.containsAll(searchResults));
- I get an error:
junit.framework.AssertionFailedError
at TestPackages.newBookingControllerTest.testOnEnter(newBookingControllerTest.java:98)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:86)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:74)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:211)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:67)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)
Can anyone elaborate on why this happens? I can edit some source code in if you need. Thanks!

Answer 1

AssertEquals takes two parameter, so you may see compilation error.
You should be using
assertTrue(allCustomers.contains(searchResults));//meaning allCustomers indeed contains searchResults
OR
assertEquals(allCustomers.contains(searchResults), true);//Meaning boolean returned by contains api is going to be compared with true