# Use Dedicated AssertJ Assertions
# Description
AssertJ contains a rich API for writing specific assertions about different types of objects. Making use of the appropriate dedicated methods when writing certain assertions will simplify the test code and improve the corresponding failure messages. This rule finds AssertJ assertions that can be simplified and replaces them with equivalent dedicated assertions.
Requirements
- AssertJ [3.20.2 - 3.22.x]
# Benefits
Simplifies the test code and improves the assertion failure messages.
# Tags
# Code Changes
# Assertions with String methods
Pre
assertThat(s1.equals("str-1")).isTrue();
assertThat(s1.equalsIgnoreCase("STR-1")).isTrue();
assertThat(s1.startsWith("str")).isTrue();
assertThat(s1.contains("-")).isTrue();
assertThat(s1.endsWith("1")).isTrue();
assertThat(s1.matches("s.*")).isTrue();
assertThat("".isEmpty()).isTrue();
assertThat("\t \n ".isBlank()).isTrue();
assertThat(s1.equals("str-2")).isFalse();
assertThat(s1.equalsIgnoreCase("STR-2")).isFalse();
assertThat(s1.startsWith("---")).isFalse();
assertThat(s1.contains("---")).isFalse();
assertThat(s1.endsWith("2")).isFalse();
assertThat(s1.matches("xx.*")).isFalse();
assertThat(s1.isEmpty()).isFalse();
assertThat(s1.isBlank()).isFalse();
Post
assertThat(s1).isEqualTo("str-1");
assertThat(s1).isEqualToIgnoringCase("STR-1");
assertThat(s1).startsWith("str");
assertThat(s1).contains("-");
assertThat(s1).endsWith("1");
assertThat(s1).matches("s.*");
assertThat("").isEmpty();
assertThat("\t \n ").isBlank();
assertThat(s1).isNotEqualTo("str-2");
assertThat(s1).isNotEqualToIgnoringCase("STR-2");
assertThat(s1).doesNotStartWith("---");
assertThat(s1).doesNotContain("---");
assertThat(s1).doesNotEndWith("2");
assertThat(s1).doesNotMatch("xx.*");
assertThat(s1).isNotEmpty();
assertThat(s1).isNotBlank();
# Assertions with List methods
Pre
assertThat(stringList.equals(Arrays.asList("str-1", "str-2", "str-3"))).isTrue();
assertThat(stringList.equals(Arrays.asList("str-1", "str-3"))).isFalse();
assertThat(stringList.contains("str-1")).isTrue();
assertThat(stringList.containsAll(Arrays.asList("str-1", "str-2"))).isTrue();
assertThat(stringList.contains("str-5")).isFalse();
Post
assertThat(stringList).isEqualTo(Arrays.asList("str-1", "str-2", "str-3"));
assertThat(stringList).isNotEqualTo(Arrays.asList("str-1", "str-3"));
assertThat(stringList).contains("str-1");
assertThat(stringList).containsAll(Arrays.asList("str-1", "str-2"));
assertThat(stringList).doesNotContain("str-5");
# Assertions with Map methods
Pre
assertThat(map.containsKey("key-1")).isTrue();
assertThat(map.containsValue("value-1")).isTrue();
assertThat(map.containsKey("key-2")).isFalse();
assertThat(map.containsValue("value-2")).isFalse();
Post
assertThat(map).containsKey("key-1");
assertThat(map).containsValue("value-1");
assertThat(map).doesNotContainKey("key-2");
assertThat(map).doesNotContainValue("value-2");
# Assertions with File methods
Pre
assertThat(directory.isDirectory()).isTrue();
assertThat(directory.isAbsolute()).isTrue();
assertThat(file.exists()).isTrue();
assertThat(file.isFile()).isTrue();
assertThat(file.canRead()).isTrue();
assertThat(file.canWrite()).isTrue();
assertThat(file.isAbsolute()).isFalse();
assertThat(notExistingFile.exists()).isFalse();
Post
assertThat(directory).isDirectory();
assertThat(directory).isAbsolute();
assertThat(file).exists();
assertThat(file).isFile();
assertThat(file).canRead();
assertThat(file).canWrite();
assertThat(file).isRelative();
assertThat(notExistingFile).doesNotExist();
# Assertions with Path methods
Pre
assertThat(absolutePath.startsWith(homeDirectory)).isTrue();
assertThat(absolutePath.endsWith(Path.of("pom.xml"))).isTrue();
assertThat(absolutePath.isAbsolute()).isTrue();
assertThat(Path.of("pom.xml").isAbsolute()).isFalse();
Post
assertThat(absolutePath).startsWith(homeDirectory);
assertThat(absolutePath).endsWith(Path.of("pom.xml"));
assertThat(absolutePath).isAbsolute();
assertThat(Path.of("pom.xml")).isRelative();
Use a Java Refactoring Tool
No license required
You can review this refactoring on your code without a license by installing jSparrow to your Eclipse IDE. Install the plug-in from Eclipse IDE: Eclipse Marketplace.
System-wide Refactoring
Do you want to automate this refactoring (and many more) to your system-wide code? The automatic application of this system-wide refactoring can be unlocked by acquiring your jSparrow license.
