如何在 Eclipse 中使用任何 javac 标志编译 Web 应用程序

Question

I have a web application in which I want to retrieve method's parameter names with reflection java.lang.reflect.Method.getParameters . Howerver parameter names can be retrieved only if Java files were compiled with -parameters flag.

You can obtain the names of the formal parameters of any method or constructor with the method java.lang.reflect.Executable.getParameters. (The classes Method and Constructor extend the class Executable and therefore inherit the method Executable.getParameters.) However, .class files do not store formal parameter names by default . This is because many tools that produce and consume class files may not expect the larger static and dynamic footprint of .class files that contain parameter names. In particular, these tools would have to handle larger .class files, and the Java Virtual Machine (JVM) would use more memory. In addition, some parameter names, such as secret or password, may expose information about security-sensitive methods.

To store formal parameter names in a particular .class file, and thus enable the Reflection API to retrieve formal parameter names, compile the source file with the -parameters option to the javac compiler .

Source: https://docs.oracle.com/javase/tutorial/reflect/member/methodparameterreflection.html

How to instruct Eclipse to compile my web application with -parameters so I could later start Tomcat server in Eclipse with my code compiled with -parameters ?

Answer 1

Eclipse 有自己的 Java 编译器，可以在项目 > 属性：Java 编译器中通过勾选最后一个复选框来设置-parameters标志的等效项：存储有关方法参数的信息（可通过反射使用） （默认情况下未启用，需要 Java 8 或更高）。