Eclipse Tutorial

EMF Persisting Tutorial

Java

通常情况下，EMF生成的代码会有一个Factory类，用来创建不同的模型。

LibraryFactory factory = LibraryFactory.eINSTANCE; 

Library library = factory.createLibrary();
library.setName("Ecsoya");

Book book = factory.createBook(); 
book.setTitle("King Lear"); 

Writer writer = factory.createWriter(); 
writer.setName("William Shakespeare"); 
book.setWriter(writer);

library.getBooks().add(book);

存储

// Create a resource set to hold the resources.
//
ResourceSet resourceSet = new ResourceSetImpl();

// Register the appropriate resource factory to handle all file extensions.
//
resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap().put
    (Resource.Factory.Registry.DEFAULT_EXTENSION, 
     new XMIResourceFactoryImpl());

// Register the package to ensure it is available during loading.
//
resourceSet.getPackageRegistry().put
    (LibraryPackage.eNS_URI, 
     LibraryPackage.eINSTANCE);

try {
    Resource resource = resourceSet.createResource(URI.createURI("http:///My.library"));
    resource.getContents().add(library);
    resource.save(System.out, null);
}
catch (IOException exception) {
    exception.printStackTrace();
}

保存的模型如下：

<?xml version="1.0" encoding="ASCII"?>
<lib:Library xmi:version="2.0" xmlns:xmi="http://www.omg.org/XMI" xmlns:lib="http://ecsoya/eclipse/tutorial/library" name="Ecsoya">
    <books title="King Lear">
        <writer name="William Shakespeare"/>
    </books>
</lib:Library>

加载

try {
    // Demand load resource for this file.
    //
    Resource resource = resourceSet.getResource(uri, true);
    System.out.println("Loaded " + uri);

    // Validate the contents of the loaded resource.
    //
    for (EObject eObject : resource.getContents()) {
        Diagnostic diagnostic = Diagnostician.INSTANCE
                .validate(eObject);
        if (diagnostic.getSeverity() != Diagnostic.OK) {
            printDiagnostic(diagnostic, "");
        }
    }
} catch (RuntimeException exception) {
    System.out.println("Problem loading " + uri);
    exception.printStackTrace();
}

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