Unit Test Class with AssertJ

Table of Contents

介紹 is 、 isIn 、 isInstanceOf 等方法，提供了一組豐富的斷言和真正有用的錯誤訊息，提高了測試程式碼的可讀性，通常與 JUnit 測試一起使用， Unit Test Java AssertJ Class 流式斷言，本篇增加了範例，並透過單元測試來驗證產出結果。

檔案目錄

./
   +- src
       +- test
       |   +- org
       |       +- ruoxue
       |           +- spring_boot_168
       |               +- test
       |                   +- assertj
       |                       +- clazz
       |                           +- UnitTestClassWithAssertJTest.java

單元測試

Java AssertJ Class Unit Test 斷言類別的主要目的是取得類別以進行斷言。

is

驗證是否符合條件，若不成立，則會拋出 AssertionError 。

	@Test
	public void is() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		Condition<Class<?>> iface = new Condition<Class<?>>(c -> c.isInterface(), "interface");
		assertThat(clazz).is(iface);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		Condition<Class<?>> primitive = new Condition<Class<?>>(c -> c.isPrimitive(), "primitive");
		assertThat(clazz2).is(primitive);
	}

interface java.lang.CharSequence
int

isNot

Java AssertJ Class Unit Test 驗證是否不符合條件，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNot() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		Condition<Class<?>> iface = new Condition<Class<?>>(c -> c.isPrimitive(), "interface");
		assertThat(clazz).isNot(iface);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		Condition<Class<?>> primitive = new Condition<Class<?>>(c -> c.isInterface(), "primitive");
		assertThat(clazz2).isNot(primitive);
	}

interface java.lang.CharSequence
int

isIn

Java AssertJ Class Unit Test 驗證是否包含於陣列中，若不成立，則會拋出 AssertionError 。

	@Test
	public void isIn() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(clazz).isIn(CharSequence.class, String.class);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		assertThat(clazz2).isIn(int.class, Integer.class);
	}

interface java.lang.CharSequence
int

isNotIn

Java AssertJ Class Unit Test 驗證是否不包含於陣列中，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNotIn() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(clazz).isNotIn(int.class, Integer.class);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		assertThat(clazz2).isNotIn(CharSequence.class, String.class);
	}

interface java.lang.CharSequence
int

isInstanceOf

Java AssertJ Class Unit Test 驗證是否為指定類別實例，若不成立，則會拋出 AssertionError 。

	@Test
	public void isInstanceOf() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(new String()).isInstanceOf(clazz);

		Class<?> clazz2 = Integer.class;
		System.out.println(clazz2);
		assertThat(1).isInstanceOf(clazz2);
	}

interface java.lang.CharSequence
class java.lang.Integer

isNotInstanceOf

Java AssertJ Class Unit Test 驗證是否不為指定類別實例，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNotInstanceOf() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(1).isNotInstanceOf(clazz);

		Class<?> clazz2 = Integer.class;
		System.out.println(clazz2);
		assertThat(new String()).isNotInstanceOf(clazz2);
	}

interface java.lang.CharSequence
class java.lang.Integer

UnitTestClassWithAssertJTest.java

Java Unit Test AssertJ Class 新增單元測試，驗證是否符合預期。

package org.ruoxue.spring_boot_168.test.assertj.clazz;

import static org.assertj.core.api.Assertions.assertThat;

import org.assertj.core.api.Condition;
import org.junit.jupiter.api.Test;

public class UnitTestClassWithAssertJTest {

	@Test
	public void is() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		Condition<Class<?>> iface = new Condition<Class<?>>(c -> c.isInterface(), "interface");
		assertThat(clazz).is(iface);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		Condition<Class<?>> primitive = new Condition<Class<?>>(c -> c.isPrimitive(), "primitive");
		assertThat(clazz2).is(primitive);
	}

	@Test
	public void isNot() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		Condition<Class<?>> iface = new Condition<Class<?>>(c -> c.isPrimitive(), "interface");
		assertThat(clazz).isNot(iface);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		Condition<Class<?>> primitive = new Condition<Class<?>>(c -> c.isInterface(), "primitive");
		assertThat(clazz2).isNot(primitive);
	}

	@Test
	public void isIn() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(clazz).isIn(CharSequence.class, String.class);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		assertThat(clazz2).isIn(int.class, Integer.class);
	}

	@Test
	public void isNotIn() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(clazz).isNotIn(int.class, Integer.class);

		Class<?> clazz2 = int.class;
		System.out.println(clazz2);
		assertThat(clazz2).isNotIn(CharSequence.class, String.class);
	}

	@Test
	public void isInstanceOf() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(new String()).isInstanceOf(clazz);

		Class<?> clazz2 = Integer.class;
		System.out.println(clazz2);
		assertThat(1).isInstanceOf(clazz2);
	}

	@Test
	public void isNotInstanceOf() {
		Class<?> clazz = CharSequence.class;
		System.out.println(clazz);
		assertThat(1).isNotInstanceOf(clazz);

		Class<?> clazz2 = Integer.class;
		System.out.println(clazz2);
		assertThat(new String()).isNotInstanceOf(clazz2);
	}
}

心得分享

AssertJ Class Java Unit Test 斷言的基本方法是 assertThat 方法，提高了測試程式碼的可讀性，並且被設計為在主流 IDE 中易於使用，讓開發者將繁瑣的測試驗證過程，變為更簡單，善用 Java Unit Test AssertJ Class 將有助於驗證效率的提升。