html简单网站建设代码,旅游网站建设策划书案例,直通车关键词怎么优化,wordpress集成api作者 l Hollis来源 l Hollis#xff08;ID#xff1a;hollischuang#xff09;在日常开发中#xff0c;我们经常需要给对象进行赋值#xff0c;通常会调用其set/get方法#xff0c;有些时候#xff0c;如果我们要转换的两个对象之间属性大致相同#xff0c;会考虑使用属… 作者 l Hollis来源 l HollisIDhollischuang在日常开发中我们经常需要给对象进行赋值通常会调用其set/get方法有些时候如果我们要转换的两个对象之间属性大致相同会考虑使用属性拷贝工具进行。如我们经常在代码中会对一个数据结构封装成DO、SDO、DTO、VO等而这些Bean中的大部分属性都是一样的所以使用属性拷贝类工具可以帮助我们节省大量的set和get操作。市面上有很多类似的工具类比较常用的有1、Spring BeanUtils 2、Cglib BeanCopier 3、Apache BeanUtils 4、Apache PropertyUtils 5、Dozer那么我们到底应该选择哪种工具类更加合适呢为什么阿里巴巴Java开发手册中提到禁止使用Apache BeanUtils呢由于篇幅优先关于这几种工具类的用法及区别还有到底是什么是浅拷贝和深拷贝不在本文的讨论范围内。本文主要聚焦于对比这几个类库的性能问题。性能对比No Data No BB我们就来写代码来对比下这几种框架的性能情况。代码示例如下首先定义一个PersonDO类public class PersonDO {private Integer id;private String name;private Integer age;private Date birthday;//省略setter/getter}再定义一个PersonDTO类public class PersonDTO {private String name;private Integer age;private Date birthday;}
然后进行测试类的编写使用Spring BeanUtils进行属性拷贝private void mappingBySpringBeanUtils(PersonDO personDO, int times) {StopWatch stopwatch new StopWatch();stopwatch.start();for (int i 0; i times; i) {PersonDTO personDTO new PersonDTO();org.springframework.beans.BeanUtils.copyProperties(personDO, personDTO);}stopwatch.stop();System.out.println(mappingBySpringBeanUtils cost : stopwatch.getTotalTimeMillis());}
其中的StopWatch用于记录代码执行时间方便进行对比。使用Cglib BeanCopier进行属性拷贝private void mappingByCglibBeanCopier(PersonDO personDO, int times) {StopWatch stopwatch new StopWatch();stopwatch.start();for (int i 0; i times; i) {PersonDTO personDTO new PersonDTO();BeanCopier copier BeanCopier.create(PersonDO.class, PersonDTO.class, false);copier.copy(personDO, personDTO, null);}stopwatch.stop();System.out.println(mappingByCglibBeanCopier cost : stopwatch.getTotalTimeMillis());}
使用Apache BeanUtils进行属性拷贝private void mappingByApacheBeanUtils(PersonDO personDO, int times)throws InvocationTargetException, IllegalAccessException {StopWatch stopwatch new StopWatch();stopwatch.start();for (int i 0; i times; i) {PersonDTO personDTO new PersonDTO();BeanUtils.copyProperties(personDTO, personDO);}stopwatch.stop();System.out.println(mappingByApacheBeanUtils cost : stopwatch.getTotalTimeMillis());}
使用Apache PropertyUtils进行属性拷贝private void mappingByApachePropertyUtils(PersonDO personDO, int times)throws InvocationTargetException, IllegalAccessException, NoSuchMethodException {StopWatch stopwatch new StopWatch();stopwatch.start();for (int i 0; i times; i) {PersonDTO personDTO new PersonDTO();PropertyUtils.copyProperties(personDTO, personDO);}stopwatch.stop();System.out.println(mappingByApachePropertyUtils cost : stopwatch.getTotalTimeMillis());}
然后执行以下代码public static void main(String[] args)throws InvocationTargetException, IllegalAccessException, NoSuchMethodException {PersonDO personDO new PersonDO();personDO.setName(Hollis);personDO.setAge(26);personDO.setBirthday(new Date());personDO.setId(1);MapperTest mapperTest new MapperTest();mapperTest.mappingBySpringBeanUtils(personDO, 100);mapperTest.mappingBySpringBeanUtils(personDO, 1000);mapperTest.mappingBySpringBeanUtils(personDO, 10000);mapperTest.mappingBySpringBeanUtils(personDO, 100000);mapperTest.mappingBySpringBeanUtils(personDO, 1000000);mapperTest.mappingByCglibBeanCopier(personDO, 100);mapperTest.mappingByCglibBeanCopier(personDO, 1000);mapperTest.mappingByCglibBeanCopier(personDO, 10000);mapperTest.mappingByCglibBeanCopier(personDO, 100000);mapperTest.mappingByCglibBeanCopier(personDO, 1000000);mapperTest.mappingByApachePropertyUtils(personDO, 100);mapperTest.mappingByApachePropertyUtils(personDO, 1000);mapperTest.mappingByApachePropertyUtils(personDO, 10000);mapperTest.mappingByApachePropertyUtils(personDO, 100000);mapperTest.mappingByApachePropertyUtils(personDO, 1000000);mapperTest.mappingByApacheBeanUtils(personDO, 100);mapperTest.mappingByApacheBeanUtils(personDO, 1000);mapperTest.mappingByApacheBeanUtils(personDO, 10000);mapperTest.mappingByApacheBeanUtils(personDO, 100000);mapperTest.mappingByApacheBeanUtils(personDO, 1000000);}
得到结果如下工具类执行1000次耗时执行10000次耗时执行100000次耗时执行1000000次耗时Spring BeanUtils5ms10ms45ms169msCglib BeanCopier4ms18ms45ms91msApache PropertyUtils60ms265ms1444ms11492msApache BeanUtils138ms816ms4154ms36938msDozer566ms2254ms11136ms102965ms画了一张折线图更方便大家进行对比综上我们基本可以得出结论在性能方面Spring BeanUtils和Cglib BeanCopier表现比较不错而Apache PropertyUtils、Apache BeanUtils以及Dozer则表现的很不好。所以如果考虑性能情况的话建议大家不要选择Apache PropertyUtils、Apache BeanUtils以及Dozer等工具类。很多人会不理解为什么大名鼎鼎的Apache开源出来的的类库性能确不高呢这不像是Apache的风格呀这背后导致性能低下的原因又是什么呢其实是因为Apache BeanUtils力求做得完美, 在代码中增加了非常多的校验、兼容、日志打印等代码过度的包装导致性能下降严重。总结本文通过对比几种常见的属性拷贝的类库分析得出了这些工具类的性能情况最终也验证了《阿里巴巴Java开发手册》中提到的Apache BeanUtils 效率低的事实。但是本文只是站在性能这一单一角度进行了对比我们在选择一个工具类的时候还会有其他方面的考虑比如使用成本、理解难度、兼容性、可扩展性等对于这种拷贝类工具类我们还会考虑其功能是否完善等。就像虽然Dozer性能比较差但是他可以很好的和Spring结合可以通过配置文件等进行属性之间的映射等也受到了很多开发者的喜爱。本文用到的第三方类库的maven依赖如下!--Apache PropertyUtils、Apache BeanUtils--dependencygroupIdcommons-beanutils/groupIdartifactIdcommons-beanutils/artifactIdversion1.9.4/version/dependencydependencygroupIdcommons-logging/groupIdartifactIdcommons-logging/artifactIdversion1.1.2/version/dependency!--Spring PropertyUtils--dependencygroupIdorg.springframework/groupIdartifactIdorg.springframework.beans/artifactIdversion3.1.1.RELEASE/version/dependency!--cglib--dependencygroupIdcglib/groupIdartifactIdcglib-nodep/artifactIdversion2.2.2/version/dependency!--dozer--dependencygroupIdnet.sf.dozer/groupIdartifactIddozer/artifactIdversion5.5.1/version/dependency!--日志相关--dependencygroupIdorg.slf4j/groupIdartifactIdslf4j-api/artifactIdversion1.7.7/version/dependencydependencygroupIdorg.slf4j/groupIdartifactIdjul-to-slf4j/artifactIdversion1.7.7/version/dependencydependencygroupIdorg.slf4j/groupIdartifactIdjcl-over-slf4j/artifactIdversion1.7.7/version/dependencydependencygroupIdorg.slf4j/groupIdartifactIdlog4j-over-slf4j/artifactIdversion1.7.7/version/dependencydependencygroupIdorg.slf4j/groupIdartifactIdslf4j-jdk14/artifactIdversion1.7.7/version/dependency往期推荐
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