reflection

问题 With the release of Java 7 came the MethodHandle, which allows a user to invoke a method as if using its underlying bytecode. In particular, the MethodHandles.Lookup class provides factory methods to create method handles to access class members: The factory methods on a Lookup object correspond to all major use cases for methods, constructors, and fields. Each method handle created by a factory method is the functional equivalent of a particular bytecode behavior. Functionally, this is more

问题 With the release of Java 7 came the MethodHandle, which allows a user to invoke a method as if using its underlying bytecode. In particular, the MethodHandles.Lookup class provides factory methods to create method handles to access class members: The factory methods on a Lookup object correspond to all major use cases for methods, constructors, and fields. Each method handle created by a factory method is the functional equivalent of a particular bytecode behavior. Functionally, this is more

问题 With the release of Java 7 came the MethodHandle, which allows a user to invoke a method as if using its underlying bytecode. In particular, the MethodHandles.Lookup class provides factory methods to create method handles to access class members: The factory methods on a Lookup object correspond to all major use cases for methods, constructors, and fields. Each method handle created by a factory method is the functional equivalent of a particular bytecode behavior. Functionally, this is more

问题 With the release of Java 7 came the MethodHandle, which allows a user to invoke a method as if using its underlying bytecode. In particular, the MethodHandles.Lookup class provides factory methods to create method handles to access class members: The factory methods on a Lookup object correspond to all major use cases for methods, constructors, and fields. Each method handle created by a factory method is the functional equivalent of a particular bytecode behavior. Functionally, this is more

问题 I want to dynamically generate some kafka stream code when the program is running， but I get an exception when I compile the following code for kafka stream with scala toolbox eval： val toolbox = runtimeMirror(getClass.getClassLoader).mkToolBox() val code = """ |import org.apache.kafka.streams.scala.kstream.KStream |import org.apache.kafka.streams.scala.StreamsBuilder | |class ClassA { | def createStream(): KStream[String, String] = { | import org.apache.kafka.streams.scala

问题 I want to dynamically generate some kafka stream code when the program is running， but I get an exception when I compile the following code for kafka stream with scala toolbox eval： val toolbox = runtimeMirror(getClass.getClassLoader).mkToolBox() val code = """ |import org.apache.kafka.streams.scala.kstream.KStream |import org.apache.kafka.streams.scala.StreamsBuilder | |class ClassA { | def createStream(): KStream[String, String] = { | import org.apache.kafka.streams.scala

问题 Say I have a class CoolStorageClass , which inherits from StorageClassBase : public abstract class StorageClassBase { } public class CoolStorageClass : StorageClassBase { } Then I have a generic abstract BaseClass<T> . It is important, that T can only be of type StorageClassBase . public abstract class BaseClass<T> where T : StorageClassBase { } Then I have the implementation of the BaseClass with T as CoolStorageClass in the form of CoolClass : public class CoolClass : BaseClass

问题 Say I have a class CoolStorageClass , which inherits from StorageClassBase : public abstract class StorageClassBase { } public class CoolStorageClass : StorageClassBase { } Then I have a generic abstract BaseClass<T> . It is important, that T can only be of type StorageClassBase . public abstract class BaseClass<T> where T : StorageClassBase { } Then I have the implementation of the BaseClass with T as CoolStorageClass in the form of CoolClass : public class CoolClass : BaseClass

问题 I have an application where a user provides me with the name of a field, e.g name or costInCents , and I have to sort by that field. I have ways of guaranteeing that the field name will be correct. This application causes the complication that I simply cannot make my class Comparable and implement a specific compareTo() , since with a custom implementation of compareTo() I need to know which fields / methods to use at implementation time. So to achieve this goal, I am trying to use reflection

问题 I have an application where a user provides me with the name of a field, e.g name or costInCents , and I have to sort by that field. I have ways of guaranteeing that the field name will be correct. This application causes the complication that I simply cannot make my class Comparable and implement a specific compareTo() , since with a custom implementation of compareTo() I need to know which fields / methods to use at implementation time. So to achieve this goal, I am trying to use reflection