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ClassUtil

This class contains utility methods for working with classes and testing Object Oriented Programming questions.

Methods Available​

classHasAttribute(Class<?> testClass, String attribute)​

Checks whether the passed attribute is defined in testClass. Returns true if the attribute is defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;
}
classHasAttribute(Bubble.class, "private int x"); // returns true
classHasAttribute(Bubble.class, "private int y"); // returns false

classHasAttributes(Class<?> testClass, String... attributes)​

Checks whether all of the passed attributes are defined in testClass. Returns true if ALL of the attributes are defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;
    private int y;
}
classHasAttributes(Bubble.class, "private int x", "private int y"); // returns true
classHasAttributes(Bubble.class, "private int x"); // returns false

classHasMethod(Class<?> testClass, String method)​

Checks whether the passed method is defined in testClass. Returns true if the method is defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }
}
classHasMethod(Bubble.class, "public int getX()"); // returns true
classHasMethod(Bubble.class, "public int setX(int)"); // returns true
classHasMethod(Bubble.class, "public int getY()"); // returns false
Method Signatures

When you write method signatures to compare with the class, you shopuld omit parameter names. So a method with the signature public int setXY(int x, int y) should be written as public int setXY(int, int). The signature is CASE SENSITIVE.

classHasMethods(Class<?> testClass, String... methods)​

Checks whether all of the passed methods are defined in testClass. Returns true if ALL of the methods are defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;
    private int y;

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }
}
classHasMethods(Bubble.class, "public int getX()", "public void setX(int)"); // returns true
classHasMethods(Bubble.class, "private int getY()"); // returns false

classHasConstructor(Class<?> testClass, String constructor)​

Checks whether the passed constructor is defined in testClass. Returns true if the constructor is defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;

    public Bubble(int x) {
        this.x = x;
    }
}
classHasConstructor(Bubble.class, "public Bubble(int)"); // returns true
classHasConstructor(Bubble.class, "public Bubble()"); // returns false
Constructor Signatures

Constructor signatures follow the same pattern as shown in the classHasMethod method above.

classHasConstructors(Class<?> testClass, String... constructors)​

Checks whether all of the passed constructors are defined in testClass. Returns true if ALL of the constructors are defined, false otherwise.

Usage: for the class:

public class Bubble {
    private int x;
    private int y;

    public Bubble(int x) {
        this.x = x;
        this.y = 0
    }

    public Bubble(int x, int y) {
        this.x = x;
        this.y = y;
    }
}
classHasMethods(Bubble.class, "public Bubble(int)", "public Bubble(int, int)"); // returns true
classHasMethods(Bubble.class, "public Bubble()"); // returns false