Java tutorial
/* * Copyright (c) 2013, the Dart project authors. * * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at * * http://www.eclipse.org/legal/epl-v10.html * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. */ package com.google.dart.tools.ui.internal.formatter; import com.google.dart.tools.core.DartCore; import com.google.dart.tools.core.dart2js.ProcessRunner; import com.google.dart.tools.core.model.DartSdkManager; import com.google.dart.tools.core.utilities.general.StringUtilities; import com.google.dart.tools.core.utilities.io.FileUtilities; import com.google.dart.tools.ui.DartToolsPlugin; import com.google.dart.tools.ui.actions.DartEditorActionDefinitionIds; import com.google.dart.tools.ui.internal.text.editor.DartEditor; import org.eclipse.core.resources.IFile; import org.eclipse.core.resources.IResource; import org.eclipse.core.runtime.CoreException; import org.eclipse.core.runtime.IProgressMonitor; import org.eclipse.core.runtime.NullProgressMonitor; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.window.IShellProvider; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.widgets.Display; import org.eclipse.ui.IEditorPart; import org.eclipse.ui.IWorkbenchPage; import org.eclipse.ui.IWorkbenchWindow; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.actions.WorkspaceAction; import org.eclipse.ui.ide.ResourceUtil; import org.eclipse.ui.internal.editors.text.EditorsPlugin; import org.eclipse.ui.texteditor.AbstractDecoratedTextEditorPreferenceConstants; import org.json.JSONException; import org.json.JSONObject; import java.io.BufferedWriter; import java.io.ByteArrayInputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.UnsupportedEncodingException; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /** * Launches the <code>dartfmt</code> process collecting stdout, stderr, and exit code information. */ @SuppressWarnings("restriction") public class DartFormatter { public static class DartFmtRunner { public static FormattedSource format(final String source, final Point selection, IProgressMonitor monitor) throws IOException, CoreException { File dartfmt = DartSdkManager.getManager().getSdk().getDartFmtExecutable(); if (!dartfmt.canExecute()) { return null; } if (source.length() == 0) { FormattedSource result = new FormattedSource(); result.source = source; return result; } ProcessBuilder builder = new ProcessBuilder(); List<String> args = new ArrayList<String>(); args.add(dartfmt.getPath()); if (selection != null) { args.add(ARGS_PRESERVE_FLAG); args.add(selection.x + ":" + selection.y); } if (getMaxLineLengthEnabled() && getMaxLineLength().length() > 0) { args.add(ARGS_MAX_LINE_LEN_FLAG); args.add(getMaxLineLength()); } args.add(ARGS_MACHINE_FORMAT_FLAG); builder.command(args); builder.redirectErrorStream(true); ProcessRunner runner = new ProcessRunner(builder) { @Override protected void processStarted(Process process) throws IOException { BufferedWriter writer = new BufferedWriter( new OutputStreamWriter(process.getOutputStream(), "UTF-8"), source.length()); writer.append(source); writer.close(); } }; runner.runSync(monitor); StringBuilder sb = new StringBuilder(); if (!runner.getStdOut().isEmpty()) { sb.append(runner.getStdOut()); } //TODO (pquitslund): better error handling if (runner.getExitCode() != 0) { sb.append(runner.getStdErr()); throw new IOException(sb.toString()); } String formattedSource = sb.toString(); if (!formattedSource.startsWith("{")) { throw new IOException(formattedSource); } try { JSONObject json = new JSONObject(formattedSource); String sourceString = (String) json.get(JSON_SOURCE_KEY); JSONObject selectionJson = (JSONObject) json.get(JSON_SELECTION_KEY); //TODO (pquitslund): figure out why we (occasionally) need to remove an extra trailing NEWLINE if (sourceString.endsWith("\n\n")) { sourceString = sourceString.substring(0, sourceString.length() - 1); } // prepare FormattedSource FormattedSource result = new FormattedSource(); result.source = sourceString; result.selectionOffset = selectionJson.getInt(JSON_OFFSET_KEY); result.selectionLength = selectionJson.getInt(JSON_LENGTH_KEY); // compute change if (!sourceString.equals(source)) { int prefixLength = StringUtilities.findCommonPrefix(source, sourceString); int suffixLength = StringUtilities.findCommonSuffix(source, sourceString); String prefix = source.substring(0, prefixLength); String suffix = source.substring(source.length() - suffixLength, source.length()); int commonLength = StringUtilities.findCommonOverlap(prefix, suffix); suffixLength -= commonLength; result.changeOffset = prefixLength; result.changeLength = source.length() - prefixLength - suffixLength; int replacementEnd = sourceString.length() - suffixLength; result.changeReplacement = sourceString.substring(prefixLength, replacementEnd); } // done return result; } catch (JSONException e) { DartToolsPlugin.log(e); throw new IOException(e); } } } public static class FormatFileAction extends WorkspaceAction { private List<IFile> files = Arrays.asList(new IFile[0]); public FormatFileAction(IShellProvider provider) { super(provider, "Format"); setId(DartEditorActionDefinitionIds.QUICK_FORMAT); setActionDefinitionId(DartEditorActionDefinitionIds.QUICK_FORMAT); } @Override public void run() { for (IFile file : files) { try { format(file, new NullProgressMonitor()); } catch (Exception e) { DartCore.logError(e); } } } @Override protected String getOperationMessage() { return "Formatting;"; } @Override protected List<IFile> getSelectedResources() { @SuppressWarnings("unchecked") List<Object> res = super.getSelectedResources(); ArrayList<IFile> resources = new ArrayList<IFile>(); for (Object r : res) { if (r instanceof IFile && DartCore.isDartLikeFileName(((IResource) r).getName())) { resources.add((IFile) r); } } return resources; } @Override protected boolean updateSelection(IStructuredSelection selection) { files = getSelectedResources(); return !files.isEmpty(); } } /** * Holder for formatted source and selection info. */ public static class FormattedSource { public int selectionOffset; public int selectionLength; public String source; public int changeOffset; public int changeLength; public String changeReplacement; } /** * Preference key for showing migrating print margin preferences. */ private final static String PRINT_MARGIN_MIGRATED = "dart-printMargin-migrated"; /** * Preference key for showing print margin ruler. */ public final static String PRINT_MARGIN = "dart-printMargin"; /** * Preference key for print margin ruler color. */ public final static String PRINT_MARGIN_COLOR = AbstractDecoratedTextEditorPreferenceConstants.EDITOR_PRINT_MARGIN_COLOR; /** * Preference key for print margin ruler column. */ public final static String PRINT_MARGIN_COLUMN = "dart-printMarginColumn"; private static final String ARGS_MACHINE_FORMAT_FLAG = "-m"; private static final String ARGS_MAX_LINE_LEN_FLAG = "-l"; private static final String ARGS_PRESERVE_FLAG = "--preserve"; private static final String JSON_LENGTH_KEY = "length"; private static final String JSON_OFFSET_KEY = "offset"; private static final String JSON_SELECTION_KEY = "selection"; private static final String JSON_SOURCE_KEY = "source"; public static void ensurePrintMarginPreferencesMigrated() { IPreferenceStore store = EditorsPlugin.getDefault().getPreferenceStore(); if (!store.getBoolean(PRINT_MARGIN_MIGRATED)) { store.setValue(PRINT_MARGIN_COLUMN, store.getString(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_PRINT_MARGIN_COLUMN)); store.setValue(PRINT_MARGIN, store.getString(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_PRINT_MARGIN)); store.setValue(PRINT_MARGIN_MIGRATED, true); } } /** * Run the formatter on the given input file. * * @param file the source to pass to the formatter * @param selection the selection info to pass into the formatter * @param monitor the monitor for displaying progress * @throws IOException if an exception was thrown during execution * @throws CoreException if an exception occurs in file refresh */ public static void format(IFile file, IProgressMonitor monitor) throws IOException, CoreException { if (file == null || DartCore.isPackagesResource(file)) { return; } DartEditor editor = getDirtyEditor(file); if (editor != null) { // Delegate to the editor if possible editor.doFormat(); } else { formatFile(file, monitor); } } /** * Run the formatter on the given input source. * * @param source the source to pass to the formatter * @param selection the selection info to pass into the formatter * @param monitor the monitor for displaying progress * @throws IOException if an exception was thrown during execution * @throws CoreException if an exception occurs in file refresh * @return the formatted source (or null in case formatting could not be executed) */ public static FormattedSource format(final String source, final Point selection, IProgressMonitor monitor) throws IOException, CoreException { return DartFmtRunner.format(source, selection, monitor); } public static String getMaxLineLength() { return EditorsPlugin.getDefault().getPreferenceStore().getString(PRINT_MARGIN_COLUMN); } public static boolean getMaxLineLengthEnabled() { return EditorsPlugin.getDefault().getPreferenceStore().getBoolean(PRINT_MARGIN); } public static boolean isAvailable() { return DartSdkManager.getManager().getSdk().getDartFmtExecutable().canExecute(); } public static void setMaxLineLength(String maxLineLength) { EditorsPlugin.getDefault().getPreferenceStore().setValue(PRINT_MARGIN_COLUMN, maxLineLength); } public static void setMaxLineLengthEnabled(boolean enabled) { EditorsPlugin.getDefault().getPreferenceStore().setValue(PRINT_MARGIN, enabled); } private static IEditorPart findEditor(final IWorkbenchPage activePage, final IFile file) { final IEditorPart[] editor = new IEditorPart[1]; Display.getDefault().syncExec(new Runnable() { @Override public void run() { editor[0] = ResourceUtil.findEditor(activePage, file); } }); return editor[0]; } private static void formatFile(IFile file, IProgressMonitor monitor) throws UnsupportedEncodingException, CoreException, IOException { Reader reader = new InputStreamReader(file.getContents(), file.getCharset()); String contents = FileUtilities.getContents(reader); if (contents != null) { FormattedSource result = format(contents, null, monitor); if (!contents.equals(result.source)) { InputStream stream = new ByteArrayInputStream(result.source.getBytes("UTF-8")); file.setContents(stream, IResource.KEEP_HISTORY, monitor); } } } private static IWorkbenchPage getActivePage() { final IWorkbenchPage[] page = new IWorkbenchPage[1]; Display.getDefault().syncExec(new Runnable() { @Override public void run() { IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow(); if (window != null) { page[0] = window.getActivePage(); } } }); return page[0]; } private static DartEditor getDirtyEditor(IFile file) { IWorkbenchPage activePage = getActivePage(); if (activePage != null) { IEditorPart editor = findEditor(activePage, file); if (editor instanceof DartEditor) { if (editor.isDirty()) { return (DartEditor) editor; } } } return null; } }