AssertJ String Assertions

Table of Contents

提供驗證包含、不包含指定的字串等方法， AssertJ 是一個 Java 庫，提供了一組豐富的斷言和真正有用的錯誤訊息，類似的流暢或鍊式寫法，語法跟自然語言相近，對於編寫測試時力求容易閱讀及維護這之上提供了相當大的改進， Asserting String with AssertJ 使用流式斷言，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
       |                       +- string
       |                           +- AssertJStringAssertionsTest.java

單元測試

String Elements with AssertJ 斷言字串的主要目的是取得字串以進行斷言。

contains

驗證包含指定的字串，若不成立，則會拋出 AssertionError 。

	@Test
	public void contains() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).contains("AssertJ", "155");
		assertThat(value).contains("rtJ", "5");
	}

AssertJ 155

doesNotContain

String Elements with AssertJ 驗證不包含指定的字串，若不成立，則會拋出 AssertionError 。

	@Test
	public void doesNotContain() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).doesNotContain("JUnit", "151");
		assertThat(value).doesNotContain("nit", "51");
	}

AssertJ 155

containsOnlyOnce

String Elements with AssertJ 驗證包含只出現一次的字串，若不成立，則會拋出 AssertionError 。

	@Test
	public void containsOnlyOnce() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).containsOnlyOnce("rtJ");
		assertThat(value).containsOnlyOnce("55");
	}

AssertJ 155

containsOnlyWhitespaces

String Elements with AssertJ 驗證只包含空白，若不成立，則會拋出 AssertionError 。

	@Test
	public void containsOnlyWhitespaces() {
		String value = " ";
		System.out.println(value);
		assertThat(value).containsOnlyWhitespaces();
		value = "   ";
		System.out.println(value);
		assertThat(value).containsOnlyWhitespaces();
	}

doesNotContainOnlyWhitespaces

Testing Java String with AssertJ 驗證不只包含空白，若不成立，則會拋出 AssertionError 。

	@Test
	public void doesNotContainOnlyWhitespaces() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).doesNotContainOnlyWhitespaces();
		value = "AssertJ ";
		System.out.println(value);
		assertThat(value).doesNotContainOnlyWhitespaces();
	}

AssertJ 155
AssertJ

containsOnlyDigits

Testing Java String with AssertJ 驗證只包含數字，若不成立，則會拋出 AssertionError 。

	@Test
	public void containsOnlyDigits() {
		String value = "155";
		System.out.println(value);
		assertThat(value).containsOnlyDigits();
		value = "5";
		System.out.println(value);
		assertThat(value).containsOnlyDigits();
	}

155
5

containsWhitespaces

Testing Java String with AssertJ 驗證包含空白，若不成立，則會拋出 AssertionError 。

	@Test
	public void containsWhitespaces() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).containsWhitespaces();
		value = " ";
		System.out.println(value);
		assertThat(value).containsWhitespaces();
	}

AssertJ 155

doesNotContainAnyWhitespaces

Testing Java String with AssertJ 驗證不包含任何空白，若不成立，則會拋出 AssertionError 。

	@Test
	public void doesNotContainAnyWhitespaces() {
		String value = "AssertJ155";
		System.out.println(value);
		assertThat(value).doesNotContainAnyWhitespaces();
		value = "AssertJ";
		System.out.println(value);
		assertThat(value).doesNotContainAnyWhitespaces();
	}

AssertJ155
AssertJ

AssertJStringAssertionsTest.java

Testing Java String with AssertJ 新增單元測試，驗證是否符合預期。

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

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

import org.junit.jupiter.api.Test;

public class AssertJStringAssertionsTest {

	@Test
	public void contains() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).contains("AssertJ", "155");
		assertThat(value).contains("rtJ", "5");
	}

	@Test
	public void doesNotContain() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).doesNotContain("JUnit", "151");
		assertThat(value).doesNotContain("nit", "51");
	}

	@Test
	public void containsOnlyOnce() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).containsOnlyOnce("rtJ");
		assertThat(value).containsOnlyOnce("55");
	}

	@Test
	public void containsOnlyWhitespaces() {
		String value = " ";
		System.out.println(value);
		assertThat(value).containsOnlyWhitespaces();
		value = "   ";
		System.out.println(value);
		assertThat(value).containsOnlyWhitespaces();
	}

	@Test
	public void doesNotContainOnlyWhitespaces() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).doesNotContainOnlyWhitespaces();
		value = "AssertJ ";
		System.out.println(value);
		assertThat(value).doesNotContainOnlyWhitespaces();
	}

	@Test
	public void containsOnlyDigits() {
		String value = "155";
		System.out.println(value);
		assertThat(value).containsOnlyDigits();
		value = "5";
		System.out.println(value);
		assertThat(value).containsOnlyDigits();
	}

	@Test
	public void containsWhitespaces() {
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).containsWhitespaces();
		value = " ";
		System.out.println(value);
		assertThat(value).containsWhitespaces();
	}

	@Test
	public void doesNotContainAnyWhitespaces() {
		String value = "AssertJ155";
		System.out.println(value);
		assertThat(value).doesNotContainAnyWhitespaces();
		value = "AssertJ";
		System.out.println(value);
		assertThat(value).doesNotContainAnyWhitespaces();
	}
}