Here's the code. The code in method test and test2 are different because the parameter passed to Test constructor are different. Actually, if I change any parameter to null, intellij stops reporting the duplication. Is there any way to fix this?
---- Updated --------
I pass 2 functions doing totally different things but intellij still reports duplication
public class TestMain {
public void test(int a)
{
System.out.println("haha");
System.out.println("hahaa");
TestMain testMain = new TestMain();
new Test(testMain::test3);
System.out.println("hahaaa");
}
public void test2(int a)
{
System.out.println("haha");
System.out.println("hahaa");
TestMain testMain = new TestMain();
new Test(testMain::still_dup);
System.out.println("hahaaa");
}
public void test3(int a) {
System.out.println("abc");
}
public void still_dup(int a) {
String b = "edf";
b.toLowerCase();
}
public class Test {
Test(handler h) {
}
}
public interface handler<M> {
void entitySelector(int a);
}
public static void main(String[] args) {
TestMain test = new TestMain();
test.test(1);
System.out.println("-------");
test.test2(2);
}
}
I think the best way to fix this is to replace test and test2 by a single method. You don't have to distinguish what to pass the constructor because it's the current method. This might be the reason why code duplication is reported. The methods can be replaced by a single one without problems.
Related
I have a sample code (pasted below). I am using Xunit, NSubstitute and NCrunch. When I run the test in Visual Studio's Test Explorer, the test passes. When I debug, the test runs correctly. With NCrunch, I am facing a bizzare behavior, the test passes, and then fails, then it passes and then fails, and it continues like that.
[Fact]
public void Test()
{
var drink = Substitute.For<IDrink>();
var greetings = new Greetings();
var derived = new Derived();
derived.Test(drink, greetings);
}
public class Greetings
{
public string Message { get; set; }
}
public interface IDrink
{
void Prepare(Greetings greetings);
}
public abstract class Base
{
public abstract void Test(IDrink drink, Greetings greetings);
}
public class Derived : Base
{
public override void Test(IDrink drink, Greetings greetings)
{
drink.Prepare(greetings); /////////// The error is here
}
}
public class NullDerived : Derived
{
public override void Test(IDrink drink, Greetings greetings)
{
throw new Exception("No value found");
}
}
The error NCrunch throwing is:
NSubstitute.Exceptions.RedundantArgumentMatcherException: Some argument specifications (e.g. Arg.Is, Arg.Any) were left over after the last call.
This is often caused by using an argument spec with a call to a member NSubstitute does not handle (such as a non-virtual member or a call to an instance which is not a substitute), or for a purpose other than specifying a call (such as using an arg spec as a return value). For example:....
I have tried to remove the parameter from Prepare(Greetings greetings) method, then NCrunch passes the test every single time.
As the error is suggesting, I am not passing the paramaters from the Test correctly.
My question is: What is the correct way of passing the greetings object to Prepare method. I have tried Arg.Any but it didn't work.
Any help is appreciated.
Edit 1:
I am seeing the same behvarior using Reshaper's Unit Test Coverage.
Can anyone advise if it is possible to use an expectations/verifications to test that private methods are being called the-right-number-of-times/right-parameters.
The Class under test has been Mocked-Up - with one private method overridden.
Am Testing a public method which calls into a number of private methods.
I wish to know if it is possible to verify the calls to other private methods which will be called when the public method is being executed ?
Some idea of the code/class under test;
public class UnderTest {
public void methodPublic(arg 1){
.....
methodPrivate1(var1);
....
methodPrivate2(var2);
}
private void methodPrivate1(var1){
//do stuff
}
private void methodPrivate2(var1){
//do stuff
}
}
In my test case
#Test
public void stateBasedTestMethod()
{
UnderTest underTest;
new MockUp<UnderTest>() {
#Mock(invocations = 1)
private void methodPrivate2(var1) {
//do nothing in the mocked case
}
};
underTest = new UnderTest();
underTest.methodPublic(arg1);
new Verifications() {{
// Is there a way to test that methodPrivate1 has been called-once/with-expected-arguments
}};
}
Edited in response to the answer from Rogério.
I am using jmockit 1.12
and the Verifications is FAILING as the method using the provided solution is invoking the method twice as I thought from the JMockit documentation.
Failure Trace;
mockit.internal.UnexpectedInvocation: Expected exactly 1 invocation(s) of MyHelperTest$1#method3..., but was invoked 2 time(s)
Included is the full code I am using for this.
As described above - my goal is to mock one of the private methods to do nothing.
And ensure that I can verify that the other private method is called only once.
Thanks in advance and hopefully will get a better understanding if this is possible with Jmockit.
Test Code.
public class MyHelperTest {
#Test
public void testHelper(#Mocked final MyDependent myDependent) {
final MyHelper myHelper;
new MockUp<MyHelper>() {
#Mock(invocations = 1)
private void method3(MyDependent myTable) {
System.out.println("In Mocked Method");
//do nothing in the mocked case
}
};
myHelper = new MyHelper();
myHelper.method1(myDependent);
new Verifications() {{
invoke(myHelper, "method2", myDependent); times = 1;
}};
}
}
Class under test.
public class MyHelper {
public void method1(MyDependent myDependent){
method2(myDependent);
}
private void method2(MyDependent myDependent) {
myDependent.setValue(1);
method3(myDependent);
}
private void method3(MyDependent myDependent) {
myDependent.setValue(2);
}
}
Dependent Class
public class MyDependent {
private int value;
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
}
It's possible, though not recommended to mock private methods.
Using the Expectations API:
#Tested #Mocked MyHelper myHelper;
#Test
public void testHelper(#Mocked final MyDependent myDependent)
{
new NonStrictExpectations() {{ invoke(myHelper, "method3", myDependent); }};
myHelper.method1(myDependent);
new Verifications() {{ invoke(myHelper, "method2", myDependent); times = 1; }};
}
... where the invoke(...) method is statically imported from class mockit.Deencapsulation.
I noticed that if a method you want to verify is not mocked, when the static block in an Expectations or Verifications instance is executed that the code calls the method that you are trying to mark as expected or verify.
This might explain the extra invocation that you are seeing.
One suggestion: if you are already mocking the class with MockUp (and thus creating an anonymous subclass) so you can override the private method, why not change the access of the overridden private method to protected or public? Then you can create an expectation or verification on it.
You could also provide a public field "public int counter=0;" and have your overridden method increment the counter. Then you can use an assert on it after the test is complete.
I am looking at AspectJ to see if perhaps we can use it in our test suite.
We have a rather large third party Java communications library hardwired to use its own classes (which do not implement any interfaces) which in turn mean that we need a physical backend present and correctly configured to be able to run tests.
I am looking at our options for removing this restriction. A possibility would be to create a subclass of the troublesome classes and then ask AspectJ to simply replace "new X" with "new OurSubclassOfX" when loading the third party library, but I am new to AspectJ and from my brief skimming of the documentation this is not a typical use case.
Can AspectJ do this? What would the configuration snippet be?
Yes, this is possible. Let us assume you have a hard-wired class, possibly fetching something from a database, and want to mock it via an aspect:
package de.scrum_master.aop.app;
public class HardWired {
private int id;
private String name;
public HardWired(int id, String name) {
this.id = id;
this.name = name;
}
public void doSomething() {
System.out.println("Fetching values from database");
}
public int getSomething() {
return 11;
}
#Override
public String toString() {
return "HardWired [id=" + id + ", name=" + name + "]";
}
}
Then there is a little driver application using that very class (not an interface):
package de.scrum_master.aop.app;
public class Application {
public static void main(String[] args) {
HardWired hw = new HardWired(999, "My object");
System.out.println(hw);
hw.doSomething();
System.out.println(hw.getSomething());
}
}
The output is as follows:
HardWired [id=999, name=My object]
Fetching values from database
11
Now you define your derived mock class which should replace the original for testing purposes:
package de.scrum_master.aop.mock;
import de.scrum_master.aop.app.HardWired;
public class HardWiredMock extends HardWired {
public HardWiredMock(int id, String name) {
super(id, name);
}
#Override
public void doSomething() {
System.out.println("Mocking database values");
}
#Override
public int getSomething() {
return 22;
}
#Override
public String toString() {
return "Mocked: " + super.toString();
}
}
And finally you define an aspect with a simple pointcut and advice to replace the original value during each constructor call:
package de.scrum_master.aop.aspect;
import de.scrum_master.aop.app.HardWired;
import de.scrum_master.aop.mock.HardWiredMock;
public aspect MockInjector {
HardWired around(int p1, String p2) : call(HardWired.new(int, String)) && args(p1, p2) {
return new HardWiredMock(p1, p2);
}
}
The output changes as desired:
Mocked: HardWired [id=999, name=My object]
Mocking database values
22
You do that once per class and constructor and are fine. In order to generalise the approach you would need joinpoint properties and, depending on how far you want to go, maybe reflection, but this here is pretty straightforward. Enjoy!
I have a class that only have main which read in some txt and do the algorithms.
my class is look like:
class doThejob{
public static void main(String args[]){
//*****start part A******
//do the reading from text file, and tokenize it
// process into the form I need,
//about 10-30 lines of codes
//******End of part A*****
//then run the algorithms
algorithm alg=new aglorithm();
Object output = alg.x(input);
//****Part B**** output to txt, about 10~40 lines
}
}
class algorithm{
private void a(Object x){
//do something
return (Object)result;
}
}
Can anyone tell me should I extract those part A and part B to a new class ,and then setup them as a public method .like below
class Io{
public Object readFromTxt(String path){
}
public void outputToTxt(String path){
}
}
And if I setup them , and then use it like below, is that more OOP?
class doThejob{
public static void main(String args[]){
Io dataProcess= new Io();
Object input = dataProcess.readFromTxt(args[0]);
algorithm alg=new aglorithm();
Object output =alg.x(input);
dataProcess.readFromTxt(args[1],output);
}
}
class algorithm{
private Object a(Object x){
//do something
}
}
Do it the way you fill is more readable.
Separating this in another class is according to the Single Responsability Principle. It will help making the code more readable and easy to change later on.
If you want to expand more on this, you could create an interface (eg.: IIO) for input and output. This way you can implement this interface in the IO class, renaming it to FileIO. Anytime you want to create another form of IO, like database access, you just have to create a DatabaseIO class that implements this interface and change the instance in the main method for this new type:
public interface IIO
{
string Read();
void Write(string text);
}
public class FileIO : IIO
{
string path;
public FileIO(string filePath)
{
path = filePath;
}
public string Read()
{
// read from file and return contents
}
public void Write(string text)
{
// write to file
}
}
public class SqlServerIO : IIO
{
SqlConnection conn;
public SqlServerIO(string connectionStringName)
{
// create the connection
}
public string Read()
{
// read from database
}
public void Write(string text)
{
// write to database
}
}
Extracting interfaces makes the code more maintenable by alowing to switch implementations anytime without messing with working code. It also facilitates unit testing.
Suppose there's 2 classes : A and B.
A can operate on B.
I need to be able to query all B instances that A has operated on.
And for a specific B instance, I need to be able to query all A instances that have operated on it.
What's the elegant(in the OO taste..) solution for this kind of problem?
In a language like Java I would do something like:
package com.whatever.blah;
public class A {
private Set<B> patients = new HashSet<B>;
public void operateOn(B patient) {
patient.startRecoveringFromOperation(this);
patients.add(patient);
}
public List<B> getPatients() {
return patients;
}
}
public class B {
private Set<A> surgeons = new HashSet<A>;
//this has package access to `A` can access it but other classes can't
void startRecoveringFromOperation(A theSurgeon) {
surgeons.add(theSurgeon);
}
public List<A> getSurgeons() {
return surgeons;
}
}
This really isn't doing anything special, beyond using package access to allow A access to B's startRecoveringFromOperation() method while hiding the method from most other classes. In other languages you might use a different approach to accomplish this. For instance in C++ you might declare A as a friend of B instead.
import java.util.*;
class A {
void operate(B b) {
operatedOn.add(b);
b.operatedOnBy.add(this);
}
final Set<B> operatedOn = new HashSet<B>();
}
class B {
final Set<A> operatedOnBy = new HashSet<A>();
}
public class Main {
public static void main(String[] args) {
A a=new A();
B b=new B();
a.operate(b);
System.out.println(a+" "+a.operatedOn);
System.out.println(b+" "+b.operatedOnBy);
}
}