我正在使用 Eclipse 3.7 (OSGI),我可以进行手动增强(使用 Datanucleus Eclipse 插件和 datanucleus-enhancer-2.1.0-release 作为插件依赖项导入)
我正在尝试使用 API 类增强:http://www.datanucleus.org/products/accessplatform/jpa/enhancer.html#api
类路径中的 ASM 3.1 和此代码:
DataNucleusEnhancer enhancer=new DataNucleusEnhancer("JDO","ASM");
enhancer.setVerbose(true);
enhancer.addClasses(...);
enhancer.enhance();
我得到:
You have selected to use ClassEnhancer "ASM" yet the JAR for that enhancer does not seem to be in the CLASSPATH!
org.datanucleus.enhancer.NucleusEnhanceException: You have selected to use ClassEnhancer "ASM" yet the JAR for that enhancer does not seem to be in the CLASSPATH!
at org.datanucleus.enhancer.DataNucleusEnhancer.init(DataNucleusEnhancer.java:224)
at org.datanucleus.enhancer.DataNucleusEnhancer.addClasses(DataNucleusEnhancer.java:406)
使用教程中建议的代码:
JDOEnhancer enhancer = JDOHelper.getEnhancer();
enhancer.setVerbose(true);
enhancer.addClasses(...);
enhancer.enhance();
我得到:
javax.jdo.JDOFatalUserException: There are 0 services entries for the JDOEnhancer; there were no valid JDOEnhancer implementations found in the CLASSPATH. The file META-INF/services/javax.jdo.JDOEnhancer should name the implementation class.
有没有办法实现API类增强?
最佳答案
请参阅此链接 http://www.datanucleus.org/products/accessplatform_3_0/enhancer.html#runtime
特别是一句:“Runtime Enhancement 需要以下运行时依赖项:ASM 和 DataNucleus Core 库。”
所以您可能缺少 ASM 依赖项。
尝试添加这个依赖:
<dependency>
<groupId>org.ow2.asm</groupId>
<artifactId>asm</artifactId>
<version>4.2</version>
</dependency>
关于java - Datanucleus 编程 API 类增强,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19793874/