AssertJ String in Java with Examples

Table of Contents

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，驗證 String 是否相同元素、大小， AssertJ String in Java 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
       |                       +- string
       |                           +- AssertJStringWithExamplesTest.java

單元測試

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

has

驗證是否符合條件，若不成立，則會拋出 AssertionError 。

	@Test
	public void has() {
		String value = "AssertJ 155";
		System.out.println(value);
		Condition<String> length = new Condition<String>(s -> s.length() > 2, "length");
		assertThat(value).has(length);

		value = null;
		System.out.println(value);
		Condition<String> nullz = new Condition<String>(s -> s == null, "null");
		assertThat(value).has(nullz);
	}

AssertJ 155
null

hasSize

AssertJ String Java 驗證大小是否為指定值，若不成立，則會拋出 AssertionError 。

	@Test
	public void hasSize() {
		int expectedSize = 11;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSize(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSize(7);
	}

AssertJ 155
AssertJ

hasSizeBetween

AssertJ String Java 驗證大小是否介於起始值之間，若不成立，則會拋出 AssertionError 。

	@Test
	public void hasSizeBetween() {
		int expectedSize = 11;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeBetween(1, expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeBetween(1, 7);
	}

AssertJ 155
AssertJ

hasSizeGreaterThan

AssertJ String Java 驗證大小是否大於指定值，若不成立，則會拋出 AssertionError 。

	@Test
	public void hasSizeGreaterThan() {
		int expectedSize = 2;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeGreaterThan(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeGreaterThan(6);
	}

AssertJ 155
AssertJ

hasSizeLessThan

Java AssertJ String 驗證大小是否小於指定值，若不成立，則會拋出 AssertionError 。

	@Test
	public void hasSizeLessThan() {
		int expectedSize = 12;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeLessThan(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeLessThan(8);
	}

AssertJ 155
AssertJ

hasToString

Java AssertJ String 驗證 toString 是否相等，若不成立，則會拋出 AssertionError 。

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

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasToString(value.toString());
	}

AssertJ 155
AssertJ

hasSameSizeAs

Java AssertJ String 驗證大小是否相等，若不成立，則會拋出 AssertionError 。

	@Test
	public void hasSameSizeAs() {
		String value = "AssertJ 155";
		String value2 = "AssertJ 155";
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).hasSameSizeAs(value2);

		value = "AssertJ";
		value2 = "AssertJ";
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).hasSameSizeAs(value2);
	}

AssertJ 155
AssertJ 155
AssertJ
AssertJ

doesNotHave

Java AssertJ String Example 驗證是否不符合條件，若不成立，則會拋出 AssertionError 。

	@Test
	public void doesNotHave() {
		String value = "AssertJ 155";
		System.out.println(value);
		Condition<String> length = new Condition<String>(s -> s.length() > 12, "length");
		assertThat(value).doesNotHave(length);

		value = "AssertJ";
		System.out.println(value);
		Condition<String> nullz = new Condition<String>(s -> s == null, "null");
		assertThat(value).doesNotHave(nullz);
	}

AssertJ 155
AssertJ

AssertJStringWithExamplesTest.java

Java AssertJ String 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.assertj.core.api.Condition;
import org.junit.jupiter.api.Test;

public class AssertJStringWithExamplesTest {

	@Test
	public void has() {
		String value = "AssertJ 155";
		System.out.println(value);
		Condition<String> length = new Condition<String>(s -> s.length() > 2, "length");
		assertThat(value).has(length);

		value = null;
		System.out.println(value);
		Condition<String> nullz = new Condition<String>(s -> s == null, "null");
		assertThat(value).has(nullz);
	}

	@Test
	public void hasSize() {
		int expectedSize = 11;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSize(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSize(7);
	}

	@Test
	public void hasSizeBetween() {
		int expectedSize = 11;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeBetween(1, expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeBetween(1, 7);
	}

	@Test
	public void hasSizeGreaterThan() {
		int expectedSize = 2;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeGreaterThan(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeGreaterThan(6);
	}

	@Test
	public void hasSizeLessThan() {
		int expectedSize = 12;
		String value = "AssertJ 155";
		System.out.println(value);
		assertThat(value).hasSizeLessThan(expectedSize);

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasSizeLessThan(8);
	}

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

		value = "AssertJ";
		System.out.println(value);
		assertThat(value).hasToString(value.toString());
	}

	@Test
	public void hasSameSizeAs() {
		String value = "AssertJ 155";
		String value2 = "AssertJ 155";
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).hasSameSizeAs(value2);

		value = "AssertJ";
		value2 = "AssertJ";
		System.out.println(value);
		System.out.println(value2);
		assertThat(value).hasSameSizeAs(value2);
	}

	@Test
	public void doesNotHave() {
		String value = "AssertJ 155";
		System.out.println(value);
		Condition<String> length = new Condition<String>(s -> s.length() > 12, "length");
		assertThat(value).doesNotHave(length);

		value = "AssertJ";
		System.out.println(value);
		Condition<String> nullz = new Condition<String>(s -> s == null, "null");
		assertThat(value).doesNotHave(nullz);
	}
}