Introduction

When server responds a Number field with String or int or float or boolean, then the assertion can be done to check exactly it was a String or Number or boolean etc.

This is in general useful, but particularly handy when we do a conformance testing of a API specification.

Scenario - String

import org.junit.Assert;

public class StringTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        String data = "some data";

        // Assertions to validate data types
        Assert.assertTrue("Expected 'data' to be of type String.", data instanceof String);

        System.out.println("The data is confirmed to be a string!");
    }
}

Scenario - Boolean

import org.junit.Assert;

public class BooleanTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        Boolean isAvailable = true;

        // Assertions to validate data types
        Assert.assertTrue("Expected 'isAvailable' to be of type Boolean.", isAvailable instanceof Boolean);

        System.out.println("The data is confirmed to be a boolean!");
    }
}

Scenario - Int

import org.junit.Assert;

public class IntTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        Int count = 19;

        // Assertions to validate data types
        Assert.assertTrue("Expected 'count' to be of type Int.", count instanceof Int);

        System.out.println("The data is confirmed to be an integer!");
    }
}

Scenario - Double

import org.junit.Assert;

public class DoubleTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        Double price = 19.99;

        // Assertions to validate data types
        Assert.assertTrue("Expected 'price' to be of type Double.", price instanceof Double);

        System.out.println("The data is confirmed to be a double!");
    }
}

Scenario - Decimal

import org.junit.Assert;

public class DecimalTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        Decimal apr = 0.0355;

        // Assertions to validate data types
        Assert.assertTrue("Expected 'apr' to be of type Decimal.", apr instanceof Decimal);

        System.out.println("The data is confirmed to be a decimal!");
    }
}

Scenario - Float

import org.junit.Assert;

public class FloatTypeAssertion {

    public static void main(String[] args) {
        // Example response data
        Float distance = 12.75;

        // Assertions to validate data types
        Assert.assertTrue("Expected 'distance' to be of type Float.", distance instanceof Float);

        System.out.println("The data is confirmed to be a float!");
    }
}