Hello, I'm jonssonyan, a Java development engineer. Today I will share with you about the tool classes in Spring BeanUtils.copyProperties.
As Java developers, we often encounter situations where we need to copy property values from one Java object to another. In order to achieve this function, Spring provides a very convenient tool class - BeanUtils.copyProperties. This tool class can help us quickly and easily copy the attribute value of one object to another object, which is very convenient and practical.
In the Spring framework, the BeanUtils.copyProperties method is defined as follows:
public static void copyProperties(Object source, Object target)
throws BeansException;
This method receives two parameters, sourceand target. sourceIndicates the source object to be copied and targetthe target object to be assigned. We only need to call this method to copy the property values of sourcethe object to targetthe object.
BeanUtils.copyPropertiesThere are many overloaded versions of the method, which can implement various copy operations. For example, we can flexibly control the copy behavior by setting ignore empty properties or specifying a list of properties.
In addition to regular property copying, BeanUtils.copyPropertiesmethods can also handle nested property copying. That is, if the source object and the target object contain nested JavaBeanobjects , BeanUtils.copyPropertiesthe method can also correctly copy the property values of the nested object to the target object.
Of course, when using BeanUtils.copyPropertiesthe method , we need to pay attention to the following points:
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The property names and types of the source and target objects must match. An exception is thrown if the property names in the source and target objects do not match, or if the property types do not match.
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If the property value in the source object is null, then the corresponding property in the target object will also be set to null. If a non-null property value already exists in the target object, then this property value will be overwritten.
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For copying of
JavaBeanobjects ,BeanUtils.copyPropertiesthe method automatically creates an instance of the target object. If the target object already exists, the source object's property values will be copied into the target object instead of creating a new object.
In general, BeanUtils.copyPropertiesmethod is a very practical tool class that can help us quickly and conveniently realize the replication of Java object properties. In the project, we can combine the features of other Spring frameworks, such as AOP, to use this method more flexibly.
I hope this article is helpful to you. If you have any questions or suggestions, please feel free to send me a private message. I'm jonssonyan, a Java programmer, see you next time.