EQUALSVERIFIER | Release Normal Jar framework performance optimization method
EQUALSVERIFIER | Release Normal Jar framework performance optimization method
introduction:
EQUALSVERIFIER is a testing tool for Equals and HashCode methods for the Java class. It can quickly generate and execute test cases to verify whether the class is correctly implemented by Equals and Hashcode.However, Equalsverifier may encounter some performance problems when dealing with large and complex classes.This article will introduce some optimization methods to improve the performance of Equalsverifier's normal jar framework.At the same time, we will also provide some Java code examples to help readers understand the implementation of these methods.
1. Use Equalsverifier to ignore the attribute
For classes containing a large amount of attributes, Equalsverifier can improve performance by ignoring certain attributes.By ignoring the attributes that do not matter or not affect the object equal, it can reduce the complexity of the generating test case and improve performance.The following is an example code that uses EQUALSVERIFIER to ignore attributes:
public class MyClass {
private String importantField;
private String unimportantField;
// omit the creation function and other methods
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null || getClass() != obj.getClass()) {
return false;
}
MyClass other = (MyClass) obj;
return Objects.equals(importantField, other.importantField);
}
@Override
public int hashCode() {
return Objects.hash(importantField);
}
}
In order to make EqualSverifier ignore `unimportantfield`, we can use the method of` Withignoredfields`:
EqualsVerifier.forClass(MyClass.class)
.withIgnoredFields("unimportantField")
.verify();
In this way, Equalsverifier will only follow the `ImportantField` and ignore the` unimportantfield`.This helps reduce the time and resources required to generate test cases.
Second, cache verified classes
EQUALSVERIFIER is accurate based on the Equals and HashCode methods based on the Java Reflection verification class.Because the REFLECTION operation is relatively heavy, it is not advisable to perform frequently, so the class that has been verified by the cache can be considered.The following is a simple example code:
public class EqualsVerifierCache {
private static Set<Class<?>> verifiedClasses = new HashSet<>();
public static void verify(Class<?> clazz) {
if (!verifiedClasses.contains(clazz)) {
EqualsVerifier.forClass(clazz).verify();
verifiedClasses.add(clazz);
}
}
}
Using this cache class, you can first check the cache before verifying the class. If the class has been verified, you can skip the verification.This can avoid repeated verification operations and reduce waste of time and resources.
3. Limit the size of the object diagram
When EQUALSVERIFIER generates the object diagram for testing, the size of the object diagram will affect performance.To alleviate this impact, we can limit the size of the generated object diagram.The following is an example:
public class MyClass {
private List<String> list;
// omit the creation function and other methods
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null || getClass() != obj.getClass()) {
return false;
}
MyClass other = (MyClass) obj;
if (list == null && other.list == null) {
return true;
}
if (list == null || other.list == null || list.size() != other.list.size()) {
return false;
}
return list.equals(other.list);
}
@Override
public int hashCode() {
return Objects.hash(list);
}
}
For the `List` attribute, we can specify the maximum size limit:
EqualsVerifier.forClass(MyClass.class)
.withPrefabValues(List.class, new ArrayList<>(), Arrays.asList("item1", "item2"))
.withCollectionFactory(ArrayList::new)
.withMaxPrefilled(10)
.verify();
In this code, the `Withmaxprefilled` specifies the largest pre -filled array size, and at the same time, the` WithCollectionFactory` and `WithprefabValues` are used to specify the customized collection factories and pre -recharge.This helps to limit the size of the object diagram and improve performance.
End words:
By adopting the above -mentioned performance optimization methods, the performance of EQUALSVERIFIER normal JAR framework can be significantly improved.When dealing with large and complex classes, you can use methods such as ignoring attributes, cache verified classes and limited object diagrams to reduce time and resource consumption.We hope that the content provided in this article will be able to help readers understand and optimize the performance of the EQUALSVERIFIER framework.
