Java tutorial
/* * Copyright (c) 2012, 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.search.internal.ui.text; import com.google.dart.tools.search.internal.ui.Messages; import com.google.dart.tools.search.internal.ui.SearchMessages; import com.google.dart.tools.search.internal.ui.SearchPluginImages; import com.google.dart.tools.search.ui.text.AbstractTextSearchResult; import com.google.dart.tools.search.ui.text.AbstractTextSearchViewPage; import com.google.dart.tools.search.ui.text.Match; import org.eclipse.core.filesystem.EFS; import org.eclipse.core.filesystem.IFileStore; import org.eclipse.core.resources.IResource; import org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.IStyledLabelProvider; import org.eclipse.jface.viewers.ILabelProviderListener; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.StyledCellLabelProvider; import org.eclipse.jface.viewers.StyledString; import org.eclipse.jface.viewers.StyledString.Styler; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.RGB; import org.eclipse.swt.graphics.TextStyle; import org.eclipse.swt.widgets.Display; import org.eclipse.ui.model.WorkbenchLabelProvider; import java.io.File; import java.util.Arrays; import java.util.Comparator; public class FileLabelProvider extends LabelProvider implements IStyledLabelProvider { public static final int SHOW_LABEL = 1; public static final int SHOW_LABEL_PATH = 2; public static final int SHOW_PATH_LABEL = 3; private static final String fgSeparatorFormat = "{0} - {1}"; //$NON-NLS-1$ private static final String fgEllipses = " ... "; //$NON-NLS-1$ private final WorkbenchLabelProvider fLabelProvider; private final AbstractTextSearchViewPage fPage; @SuppressWarnings("rawtypes") private final Comparator fMatchComparator; private final Image fLineMatchImage; private int fOrder; private static final int MIN_MATCH_CONTEXT = 10; // minimal number of characters shown after and before a match private static final Color MATCH_COUNT_COLOR = new Color(Display.getDefault(), new RGB(0, 127, 174)); // #007FAE public static final Styler MATCH_COUNT_STYLER = new Styler() { @Override public void applyStyles(TextStyle textStyle) { textStyle.foreground = MATCH_COUNT_COLOR; } }; @SuppressWarnings("rawtypes") public FileLabelProvider(AbstractTextSearchViewPage page, int orderFlag) { fLabelProvider = new WorkbenchLabelProvider(); fOrder = orderFlag; fPage = page; fLineMatchImage = SearchPluginImages.get(SearchPluginImages.IMG_OBJ_TEXT_SEARCH_LINE); fMatchComparator = new Comparator() { @Override public int compare(Object o1, Object o2) { return ((FileMatch) o1).getOriginalOffset() - ((FileMatch) o2).getOriginalOffset(); } }; } @Override public void addListener(ILabelProviderListener listener) { super.addListener(listener); fLabelProvider.addListener(listener); } @Override public void dispose() { super.dispose(); fLabelProvider.dispose(); } @Override public Image getImage(Object element) { if (element instanceof FileResource<?>) { element = ((FileResource<?>) element).getResource(); } if (element instanceof File) { //TODO(pquitslund): improve image fetching IFileStore file = EFS.getLocalFileSystem().fromLocalFile((File) element); return fLabelProvider.getImage(file); } if (element instanceof LineElement) { return fLineMatchImage; } IResource resource = (IResource) element; Image image = fLabelProvider.getImage(resource); return image; } public int getOrder() { return fOrder; } public StyledString getStyledString(File resource) { if (!resource.exists()) { return new StyledString(SearchMessages.FileLabelProvider_removed_resource_label); } String name = BasicElementLabels.getResourceName(resource); if (fOrder == SHOW_LABEL) { return getColoredLabelWithCounts(resource, new StyledString(name)); } String pathString = BasicElementLabels.getParentPathLabel(resource, false); if (fOrder == SHOW_LABEL_PATH) { StyledString str = new StyledString(name); String decorated = Messages.format(fgSeparatorFormat, new String[] { str.getString(), pathString }); StyledCellLabelProvider.styleDecoratedString(decorated, StyledString.QUALIFIER_STYLER, str); return getColoredLabelWithCounts(resource, str); } StyledString str = new StyledString(Messages.format(fgSeparatorFormat, new String[] { pathString, name })); return getColoredLabelWithCounts(resource, str); } public StyledString getStyledString(IResource resource) { if (!resource.exists()) { return new StyledString(SearchMessages.FileLabelProvider_removed_resource_label); } String name = BasicElementLabels.getResourceName(resource); if (fOrder == SHOW_LABEL) { return getColoredLabelWithCounts(resource, new StyledString(name)); } String pathString = BasicElementLabels.getPathLabel(resource.getParent().getFullPath(), false); if (fOrder == SHOW_LABEL_PATH) { StyledString str = new StyledString(name); String decorated = Messages.format(fgSeparatorFormat, new String[] { str.getString(), pathString }); StyledCellLabelProvider.styleDecoratedString(decorated, StyledString.QUALIFIER_STYLER, str); return getColoredLabelWithCounts(resource, str); } StyledString str = new StyledString(Messages.format(fgSeparatorFormat, new String[] { pathString, name })); return getColoredLabelWithCounts(resource, str); } @Override public StyledString getStyledText(Object element) { if (element instanceof LineElement) { return getLineElementLabel((LineElement) element); } if (element instanceof WorkspaceFile) { element = ((WorkspaceFile) element).getResource(); } if (element instanceof IResource) { return getStyledString((IResource) element); } if (element instanceof File) { return getStyledString((File) element); } return new StyledString("skipped [" + element.getClass() + "]: " + element.toString()); } @Override public String getText(Object object) { return getStyledText(object).getString(); } @Override public boolean isLabelProperty(Object element, String property) { return fLabelProvider.isLabelProperty(element, property); } @Override public void removeListener(ILabelProviderListener listener) { super.removeListener(listener); fLabelProvider.removeListener(listener); } public void setOrder(int orderFlag) { fOrder = orderFlag; } private int appendShortenedGap(String content, int start, int end, int charsToCut, boolean isFirst, StyledString str) { int gapLength = end - start; if (!isFirst) { gapLength -= MIN_MATCH_CONTEXT; } if (end < content.length()) { gapLength -= MIN_MATCH_CONTEXT; } if (gapLength < MIN_MATCH_CONTEXT) { // don't cut, gap is too small str.append(content.substring(start, end)); return charsToCut; } int context = MIN_MATCH_CONTEXT; if (gapLength > charsToCut) { context += gapLength - charsToCut; } if (!isFirst) { str.append(content.substring(start, start + context)); // give all extra context to the right side of a match context = MIN_MATCH_CONTEXT; } str.append(fgEllipses, StyledString.QUALIFIER_STYLER); if (end < content.length()) { str.append(content.substring(end - context, end)); } return charsToCut - gapLength + fgEllipses.length(); } private int evaluateLineStart(Match[] matches, String lineContent, int lineOffset) { int max = lineContent.length(); if (matches.length > 0) { FileMatch match = (FileMatch) matches[0]; max = match.getOriginalOffset() - lineOffset; if (max < 0) { return 0; } } for (int i = 0; i < max; i++) { char ch = lineContent.charAt(i); if (!Character.isWhitespace(ch) || ch == '\n' || ch == '\r') { return i; } } return max; } private int getCharsToCut(int contentLength, Match[] matches) { if (contentLength <= 256 || !"win32".equals(SWT.getPlatform()) || matches.length == 0) { //$NON-NLS-1$ return 0; // no shortening required } // XXX: workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=38519 return contentLength - 256 + Math.max(matches.length * fgEllipses.length(), 100); } private StyledString getColoredLabelWithCounts(Object element, StyledString coloredName) { AbstractTextSearchResult result = fPage.getInput(); if (result == null) { return coloredName; } int matchCount = result.getMatchCount(element); if (matchCount <= 1) { return coloredName; } String countInfo = Messages.format(SearchMessages.FileLabelProvider_count_format, new Integer(matchCount)); coloredName.append(' ').append(countInfo, MATCH_COUNT_STYLER); return coloredName; } @SuppressWarnings("unchecked") private StyledString getLineElementLabel(LineElement lineElement) { int lineNumber = lineElement.getLine(); String lineNumberString = Messages.format(SearchMessages.FileLabelProvider_line_number, new Integer(lineNumber)); StyledString str = new StyledString(lineNumberString, StyledString.QUALIFIER_STYLER); Match[] matches = lineElement.getMatches(fPage.getInput()); Arrays.sort(matches, fMatchComparator); String content = lineElement.getContents(); int pos = evaluateLineStart(matches, content, lineElement.getOffset()); int length = content.length(); int charsToCut = getCharsToCut(length, matches); // number of characters to leave away if the line is too long for (int i = 0; i < matches.length; i++) { FileMatch match = (FileMatch) matches[i]; int start = Math.max(match.getOriginalOffset() - lineElement.getOffset(), 0); // append gap between last match and the new one if (pos < start) { if (charsToCut > 0) { charsToCut = appendShortenedGap(content, pos, start, charsToCut, i == 0, str); } else { str.append(content.substring(pos, start)); } } // append match int end = Math.min(match.getOriginalOffset() + match.getOriginalLength() - lineElement.getOffset(), lineElement.getLength()); str.append(content.substring(start, end), DecoratingFileSearchLabelProvider.HIGHLIGHT_STYLE); pos = end; } // append rest of the line if (charsToCut > 0) { appendShortenedGap(content, pos, length, charsToCut, false, str); } else { str.append(content.substring(pos)); } return str; } }