Table of Contents
ToggleAsserting Objects with AssertJ
介紹 matches 、 satisfies 驗證是否符合條件,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, Assert Objects 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
| +- object
| +- AssertingObjectsTest.java
單元測試
Assertions Objects in Java 斷言物件的主要目的是取得物件以進行斷言。
matches
Assertions Objects in Java 驗證是否符合條件,若不成立,則會拋出 AssertionError 。
@Test
public void matches() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("AssertJ"));
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("155"));
}
AssertJ
155
matchesWithDescription
Assertions Objects in Java 驗證是否符合條件,自訂描述訊息,若不成立,則會拋出 AssertionError 。
@Test
public void matchesWithDescription() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("AssertJ"), "equals");
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("155"), "toString");
}
AssertJ
155
matchesThrowError
Assertions Objects in Java 驗證是否符合條件,自訂描述訊息,當不成立時,驗證拋出 AssertionError 。
@Test
public void matchesThrowError() {
assertThatCode(() -> {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("155"), "equals");
}).isInstanceOf(AssertionError.class);
assertThatCode(() -> {
Object value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("AssertJ"), "toString");
}).isInstanceOf(AssertionError.class);
}
AssertJ
155
satisfies
Asserting Objects with Examples 驗證是否符合條件,若不成立,則會拋出 AssertionError 。
@Test
public void satisfies() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("AssertJ");
});
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("155");
});
}
AssertJ
155
satisfiesAnyOf
Asserting Objects with Examples 驗證是否符合任一條件,若不成立,則會拋出 AssertionError 。
@Test
public void satisfiesAnyOf() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfiesAnyOf(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("AssertJ");
});
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfiesAnyOf(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("151");
});
}
AssertJ
155
satisfiesThrowError
Asserting Objects with Examples 驗證是否符合條件,當不成立時,驗證拋出 AssertionError 。
@Test
public void satisfiesThrowError() {
assertThatCode(() -> {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("JUnit");
});
}).isInstanceOf(AssertionError.class);
assertThatCode(() -> {
Object value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("151");
});
}).isInstanceOf(AssertionError.class);
}
AssertJ
155
AssertingObjectsTest.java
Asserting Objects with Examples 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.assertThat;
import static org.assertj.core.api.Assertions.assertThatCode;
import java.math.BigDecimal;
import org.junit.jupiter.api.Test;
public class AssertingObjectsTest {
@Test
public void matches() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("AssertJ"));
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("155"));
}
@Test
public void matchesWithDescription() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("AssertJ"), "equals");
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("155"), "toString");
}
@Test
public void matchesThrowError() {
assertThatCode(() -> {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).matches(o -> o.equals("155"), "equals");
}).isInstanceOf(AssertionError.class);
assertThatCode(() -> {
Object value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).matches(o -> o.toString().equals("AssertJ"), "toString");
}).isInstanceOf(AssertionError.class);
}
@Test
public void satisfies() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("AssertJ");
});
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("155");
});
}
@Test
public void satisfiesAnyOf() {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfiesAnyOf(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("AssertJ");
});
value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfiesAnyOf(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("151");
});
}
@Test
public void satisfiesThrowError() {
assertThatCode(() -> {
Object value = "AssertJ";
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
assertThat(o).isEqualTo("JUnit");
});
}).isInstanceOf(AssertionError.class);
assertThatCode(() -> {
Object value = BigDecimal.valueOf(155);
System.out.println(value);
assertThat(value).satisfies(o -> {
assertThat(o).isNotNull();
}, o -> {
assertThat(o).hasToString("151");
});
}).isInstanceOf(AssertionError.class);
}
}
心得分享
Testing Java Objects with AssertJ 快速檢查物件是否滿足所有提供的斷言,搭配使用 Predicate 與 ThrowingConsumer 等接口,根據 lambda 表達式調用,驗證是否成立,若不成立,則會拋出 AssertionError, Asserting Objects with Examples 介紹 matches 、 satisfies 等方法,提供範例參考。