Implements search function and test for search via index

src/main/java/CredentialRepository.java

@@ -2,7 +2,7 @@ import java.util.ArrayList;
 
 public class CredentialRepository implements CredentialRepositoryInterface{
 
-    private int idCounter = 0;
+    private int idCounter = 1;
     private ArrayList<Credential> credentials;
 
     public CredentialRepository()
@@ -49,9 +49,17 @@ public class CredentialRepository implements CredentialRepositoryInterface{
 
 
     @Override
-    public Credential getCredentialsViaId() {
+    public Credential getCredentialsViaId(int id) {
+
+        try{
+            return this.credentials.get(id);
+        }
+        catch (IndexOutOfBoundsException outOfBoundsException)
+        {
+           return null;
+        }
+
 
-        return null;
     }
 
     @Override

src/main/java/CredentialRepositoryInterface.java

@@ -4,7 +4,7 @@ public interface CredentialRepositoryInterface {
     void edit();
     void delete();
     Credential getCredentialsViaName(String needle);
-    Credential getCredentialsViaId();
+    Credential getCredentialsViaId(int id);
     void setCredentials();
     void getAsJSON();
     void loadCredentialsFromJSON();

src/test/java/CredentialRepositoryTest.java

@@ -30,6 +30,24 @@ class CredentialRepositoryTest {
          Assertions.assertEquals("mate", c.getPassword());
     }
 
+    @Test
+    void searchForIdInRepository() {
+
+        this.credentialRepository.createNewCredential("mock", "mock");
+        this.credentialRepository.createNewCredential("kek", "mate");
+
+        Credential c = this.credentialRepository.getCredentialsViaId(2);
+        Assertions.assertEquals("mate", c.getPassword());
+    }
+
+    @Test
+    void testSearchWithInvalidIndex() {
+
+        this.credentialRepository.createNewCredential("mock", "mock");
+
+        Assertions.assertEquals(null, this.credentialRepository.getCredentialsViaId(2));
+
+    }
 
 }