![compiling java classes compiling java classes](https://www.examtray.com/sites/default/files/styles/wordpress_800x460/public/2019-06/create-run-java-program-class-in-eclipse.jpg)
Building a JAR File of Interface Classesįirst, you need to compile the interface source files in the compute package and then build a JAR file that contains their class files.
#COMPILING JAVA CLASSES CODE#
This example separates the interfaces, remote object implementation, and client code into three packages:įirst, you need to build the interface JAR file to provide to server and client developers. Also, the Compute and Task interfaces will be downloaded from the server to the registry at runtime. You will see that the client's Pi class will be downloaded to the server at runtime.
#COMPILING JAVA CLASSES HOW TO#
In this section, you learn how to set up the JAR file, server classes, and client classes. Developers of client programs can use the Compute and the Task interfaces, contained in the JAR file, and independently develop a task and client program that uses a Compute service. Next, a developer, perhaps the same developer of the interface JAR file, would write an implementation of the Compute interface and deploy that service on a machine available to clients.
![compiling java classes compiling java classes](https://www.netiq.com/documentation/identity-manager-47-drivers/peoplesoft_52/graphics/ps50schema01build_a.png)
#COMPILING JAVA CLASSES ARCHIVE#
If you are looking to dynamically compile a class from source code, that is a whole other kettle of fish.In a real-world scenario in which a service such as the compute engine is deployed, a developer would likely create a Java Archive (JAR) file that contains the Compute and Task interfaces for server classes to implement and client programs to use. Of course the class has to be compiled and on the classpath for that to work. So: IDynamicLoad newClass = (IDynamicLoad) Class.forName(class_name).newInstance() You just have to cast the result, as the compiler can't know that the class will in fact implement IDynamicLoad. Your commented code is correct if you know that the class has a public no-arg constructor. It then runs the java compiler on it, and returns a list of name,classfile pairs (the ClassInfo structure). It takes a list of strings containing Java source, extracts the package and public class/interface names and creates the corresponding directory/file hierarchy in a tmp directory.
![compiling java classes compiling java classes](https://www.baeldung.com/wp-content/uploads/2018/09/ojc-compileJava.png)
In the same vein as BalusC's answer, but a bit more automatic wrapper is here in this piece of code from my kilim distribution. properties.load(Thread.currentThread().getContextClassLoader().getResourceAsStream("ClassName.properties")) Put that file in classpath and use ClassLoader#getResourceAsStream() with a classpath-relative path. Letting java.io.File rely on current working directory is recipe for portability trouble. That said and unrelated to the actual problem: properties.load(new FileInputStream(new File("ClassName.properties"))) Otherwise you need to involve the Reflection API to access and invoke the (unknown) methods/fields. SomeInterface instance = (SomeInterface) cls.newInstance() (instance) // Should print " ".įurther use would be more easy if those classes implements a certain interface which is already in the classpath. Object instance = cls.newInstance() // Should print "world". String source = "package test public class Test ) Ĭlass cls = Class.forName("test.Test", true, classLoader) // Should print "hello". Here's a basic kickoff example (leaving obvious exception handling aside): // Prepare source somehow. This only requires the JDK being installed at the local machine on top of JRE. This can be done programmatically with the javax.tools API. How do I load a Java Class that is not compiled?