org.jboss.tools.vscode.java.internal.handlers.DocumentSymbolHandler.java Source code

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Here is the source code for org.jboss.tools.vscode.java.internal.handlers.DocumentSymbolHandler.java

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/*******************************************************************************
 * Copyright (c) 2016 Red Hat Inc. and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Red Hat Inc. - initial API and implementation
 *******************************************************************************/
package org.jboss.tools.vscode.java.internal.handlers;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.ITypeRoot;
import org.eclipse.jdt.core.JavaModelException;
import org.jboss.tools.langs.DocumentSymbolParams;
import org.jboss.tools.langs.SymbolInformation;
import org.jboss.tools.langs.base.LSPMethods;
import org.jboss.tools.vscode.internal.ipc.RequestHandler;
import org.jboss.tools.vscode.java.internal.JDTUtils;
import org.jboss.tools.vscode.java.internal.JavaLanguageServerPlugin;

public class DocumentSymbolHandler implements RequestHandler<DocumentSymbolParams, List<SymbolInformation>> {

    public DocumentSymbolHandler() {
    }

    @Override
    public boolean canHandle(String request) {
        return LSPMethods.DOCUMENT_SYMBOL.getMethod().equals(request);
    }

    private SymbolInformation[] getOutline(ITypeRoot unit) {
        try {
            IJavaElement[] elements = unit.getChildren();
            ArrayList<SymbolInformation> symbols = new ArrayList<SymbolInformation>(elements.length);
            collectChildren(unit, elements, symbols);
            return symbols.toArray(new SymbolInformation[symbols.size()]);
        } catch (JavaModelException e) {
            JavaLanguageServerPlugin.logException("Problem getting outline for" + unit.getElementName(), e);
        }
        return new SymbolInformation[0];
    }

    private void collectChildren(ITypeRoot unit, IJavaElement[] elements, ArrayList<SymbolInformation> symbols)
            throws JavaModelException {
        for (IJavaElement element : elements) {
            if (element.getElementType() == IJavaElement.TYPE) {
                collectChildren(unit, ((IType) element).getChildren(), symbols);
            }
            if (element.getElementType() != IJavaElement.FIELD && element.getElementType() != IJavaElement.METHOD) {
                continue;
            }

            SymbolInformation si = new SymbolInformation();
            si.setName(element.getElementName());
            si.setKind(new Double(mapKind(element)));
            if (element.getParent() != null)
                si.setContainerName(element.getParent().getElementName());
            si.setLocation(JDTUtils.toLocation(element));
            symbols.add(si);
        }
    }

    @Override
    public List<SymbolInformation> handle(DocumentSymbolParams param) {
        ITypeRoot unit = JDTUtils.resolveTypeRoot(param.getTextDocument().getUri());
        SymbolInformation[] elements = this.getOutline(unit);
        return Arrays.asList(elements);
    }

    public static int mapKind(IJavaElement element) {
        //      /**
        //      * A symbol kind.
        //      */
        //      export enum SymbolKind {
        //        File = 1,
        //        Module = 2,
        //        Namespace = 3,
        //        Package = 4,
        //        Class = 5,
        //        Method = 6,
        //        Property = 7,
        //        Field = 8,
        //        Constructor = 9,
        //        Enum = 10,
        //        Interface = 11,
        //        Function = 12,
        //        Variable = 13,
        //        Constant = 14,
        //        String = 15,
        //        Number = 16,
        //        Boolean = 17,
        //        Array = 18,
        //      }
        switch (element.getElementType()) {
        case IJavaElement.ANNOTATION:
            return 7; // TODO: find a better mapping 
        case IJavaElement.CLASS_FILE:
        case IJavaElement.COMPILATION_UNIT:
            return 1;
        case IJavaElement.FIELD:
            return 8;
        case IJavaElement.IMPORT_CONTAINER:
        case IJavaElement.IMPORT_DECLARATION:
            return 2;
        case IJavaElement.INITIALIZER:
            return 9;
        case IJavaElement.LOCAL_VARIABLE:
        case IJavaElement.TYPE_PARAMETER:
            return 13;
        case IJavaElement.METHOD:
            return 12;
        case IJavaElement.PACKAGE_DECLARATION:
            return 3;
        case IJavaElement.TYPE:
            try {
                return (((IType) element).isInterface() ? 11 : 5);
            } catch (JavaModelException e) {
                return 5; //fallback 
            }
        }
        return 15;
    }

}