在xtext中自动格式化

时间:2015-06-29 13:25:20

标签: eclipse-plugin xtext xtend

我想问一下,有没有办法在没有(ctrl + shift + f)或从偏好菜单打开的情况下自动在xtext中进行格式化。我真正想要的是每当用户完成编写代码时,它就会自动格式化(或在运行时),而不需要(ctrl + shift + f)。

1 个答案:

答案 0 :(得分:3)

有一种方法可以做到这一点,称为“AutoEdit”。这并不是用户完成写作的时间,而是每个令牌。这至少是我所做的。你可以肯定改变它。我将举一个例子,我为自己的项目实现了自己。它基本上会在用户输入时将每个关键字大写(由空格和终止线触发)。

这是一个UI的事情。所以,在你的UI项目中:

在MyDslUiModule.java中你需要附加你的AutoEdit自定义类,如下所示:

public Class<? extends DefaultAutoEditStrategyProvider> bindDefaultAutoEditStrategyProvider() 
{
    return MyDslAutoEditStrategyProvider.class;
}

我们的类将被称为MyDslAutoEditStrategyProvider,因此,请继续在MyDslAutoEditStrategyProvider.java文件中创建它。我有这样做我在介绍中解释的那样:

import java.util.Set;

import org.eclipse.jface.text.DocumentCommand;
import org.eclipse.jface.text.IAutoEditStrategy;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.xtext.GrammarUtil;
import org.eclipse.xtext.IGrammarAccess;
import org.eclipse.xtext.ui.editor.autoedit.DefaultAutoEditStrategyProvider;
import org.eclipse.xtext.ui.editor.model.XtextDocument;

import com.google.inject.Inject;
import com.google.inject.Provider;

public class MyDslAutoEditStrategyProvider extends DefaultAutoEditStrategyProvider {

@Inject
Provider<IGrammarAccess> iGrammar;

private Set<String> KWDS;

@Override
protected void configure(IEditStrategyAcceptor acceptor) {

    KWDS = GrammarUtil.getAllKeywords(iGrammar.get().getGrammar());

    IAutoEditStrategy strategy = new IAutoEditStrategy() 
    {

        @Override
        public void customizeDocumentCommand(IDocument document, DocumentCommand command) 
        {
            if ( command.text.length() == 0 || command.text.charAt(0) > ' ') return;

            IRegion reg = ((XtextDocument) document).getLastDamage();

            try {
                String token = document.get(reg.getOffset(), reg.getLength());
                String possibleKWD = token.toLowerCase();
                if ( token.equals(possibleKWD.toUpperCase()) || !KWDS.contains(possibleKWD) ) return;
                document.replace(reg.getOffset(), reg.getLength(), possibleKWD.toUpperCase());

            } 
            catch (Exception e) 
            {
                System.out.println("AutoEdit error.\n" + e.getMessage());   
            }
        }
    };

    acceptor.accept(strategy, IDocument.DEFAULT_CONTENT_TYPE);

    super.configure(acceptor);

    }
}

我假设你说“用户完成写作”可以作为“用户保存文件”。如果是这样,这里是如何在保存时触发格式化程序:

MyDslUiModule.java中的

public Class<? extends XtextDocumentProvider> bindXtextDocumentProvider() 
{
    return MyDslDocumentProvider.class;
}

创建MyDslDocumentProvider类:

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jface.text.IDocument;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.handlers.IHandlerService;
import org.eclipse.xtext.ui.editor.model.XtextDocumentProvider;

public class MyDslDocumentProvider extends XtextDocumentProvider 
{
    @Override
    protected void doSaveDocument(IProgressMonitor monitor, Object element, IDocument document, boolean overwrite)
            throws CoreException {
        IHandlerService service = (IHandlerService) PlatformUI.getWorkbench().getService(IHandlerService.class);
        try {
            service.executeCommand("org.eclipse.xtext.ui.FormatAction", null);
        } catch (Exception e) 
        {
            e.printStackTrace();
        }
        super.doSaveDocument(monitor, element, document, overwrite);
    }
}