AssertJ Object Methods

Table of Contents

驗證 Object 是否為空值、空集合、指定類別實例、物件相等，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，使用 AssertJ Object Java Methods 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
       |                       +- object
       |                           +- AssertJObjectMethodsTest.java

單元測試

AssertJ Object Methods Java 斷言物件的主要目的是取得物件以進行斷言。

isNull

驗證是否為空值，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNull() {
		Object value = null;
		System.out.println(value);
		assertThat(value).isNull();

		Object value2 = null;
		System.out.println(value2);
		assertThat(value2).isNull();
	}

null
null

isNotNull

AssertJ Object Methods Java 驗證是否不為空值，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNotNull() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isNotNull();

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isNotNull();
	}

AssertJ
155

isEqualTo

AssertJ Object Methods in Java 驗證物件是否相等，若不成立，則會拋出 AssertionError 。

	@Test
	public void isEqualTo() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isEqualTo("AssertJ");

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isEqualTo(BigDecimal.valueOf(155));
	}

AssertJ
155

isNotEqualTo

AssertJ Object Methods in Java 驗證物件是否不相等，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNotEqualTo() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isNotEqualTo("155");

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isNotEqualTo(155);
	}

AssertJ
155

isSameAs

AssertJ Object Functions in Java 驗證實例是否相等，若不成立，則會拋出 AssertionError 。

	@Test
	public void isSameAs() {
		Object value = "AssertJ";
		Object value2 = value;
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isSameAs(value2);

		value = BigDecimal.valueOf(155);
		value2 = value;
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isSameAs(value2);
	}

AssertJ
AssertJ
155
155

isNotSameAs

AssertJ Object Functions in Java 驗證實例是否不相等，若不成立，則會拋出 AssertionError 。

	@Test
	public void isNotSameAs() {
		Object value = "AssertJ";
		Object value2 = new String("AssertJ");
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isNotSameAs(value2);

		value = BigDecimal.valueOf(155);
		value2 = BigDecimal.valueOf(155);
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isNotSameAs(value2);
	}

AssertJ
AssertJ
155
155

AssertJObjectMethodsTest.java

AssertJ Object Methods in Java 新增單元測試，驗證是否符合預期。

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

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

import java.math.BigDecimal;
import org.junit.jupiter.api.Test;

public class AssertJObjectMethodsTest {

	@Test
	public void isNull() {
		Object value = null;
		System.out.println(value);
		assertThat(value).isNull();

		Object value2 = null;
		System.out.println(value2);
		assertThat(value2).isNull();
	}

	@Test
	public void isNotNull() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isNotNull();

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isNotNull();
	}

	@Test
	public void isEqualTo() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isEqualTo("AssertJ");

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isEqualTo(BigDecimal.valueOf(155));
	}

	@Test
	public void isNotEqualTo() {
		Object value = "AssertJ";
		System.out.println(value);
		assertThat(value).isNotEqualTo("155");

		value = BigDecimal.valueOf(155);
		System.out.println(value);
		assertThat(value).isNotEqualTo(155);
	}

	@Test
	public void isSameAs() {
		Object value = "AssertJ";
		Object value2 = value;
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isSameAs(value2);

		value = BigDecimal.valueOf(155);
		value2 = value;
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isSameAs(value2);
	}

	@Test
	public void isNotSameAs() {
		Object value = "AssertJ";
		Object value2 = new String("AssertJ");
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isNotSameAs(value2);

		value = BigDecimal.valueOf(155);
		value2 = BigDecimal.valueOf(155);
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).isNotSameAs(value2);
	}
}

心得分享

AssertJ Object Functions in Java 為用 Java 編寫的測試程式提供了流暢的斷言語句，這些斷言語句通常與 JUnit 測試一起使用， AssertJ 斷言的基本方法是 assertThat 方法，善用 AssertJ Object Methods in Java 將有助於驗證效率的提升。