Java tutorial
/** * Copyright (c) 2013-2016 Angelo ZERR. * 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: * Angelo Zerr <angelo.zerr@gmail.com> - initial API and implementation */ package tern.eclipse.ide.ui.utils; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URL; import java.util.Arrays; import java.util.Collection; import java.util.List; import org.eclipse.core.runtime.Platform; import org.eclipse.jface.internal.text.html.HTMLPrinter; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.swt.graphics.FontData; import org.eclipse.swt.graphics.RGB; import org.osgi.framework.Bundle; import tern.eclipse.ide.internal.ui.TernUIMessages; import tern.eclipse.ide.internal.ui.Trace; import tern.eclipse.ide.ui.TernUIPlugin; import tern.eclipse.jface.text.HoverLocationListener; import tern.server.protocol.completions.Parameter; import tern.server.protocol.completions.TernCompletionItem; import tern.utils.StringUtils; /** * Provides a set of convenience methods for creating HTML info for tern content * assist and hover. * */ public class HTMLTernPrinter { /** * Style sheets content. */ private static String fgStyleSheet; private static RGB colorInfoBackround = null; private static RGB colorInfoForeground = null; private HTMLTernPrinter() { } public static void setColorInfoBackround(RGB colorInfoBackround) { HTMLTernPrinter.colorInfoBackround = colorInfoBackround; } public static void setColorInfoForeground(RGB colorInfoForeground) { HTMLTernPrinter.colorInfoForeground = colorInfoForeground; } public static String getAdditionalProposalInfo(TernCompletionItem item, Boolean guess) { StringBuffer buffer = new StringBuffer(); ImageDescriptor descriptor = TernUIPlugin.getTernDescriptorManager().getImageDescriptor(item); startPage(buffer, getTitle(item), descriptor); // doc addDocContent(buffer, item.getDoc()); startDefinitionList(buffer); // parameters addParametersContent(buffer, item.getParameters()); // return type addReturnTypeContent(buffer, item.getJsType()); // origin addOriginContent(buffer, item.getOrigin()); // guess? addGuessContent(buffer, guess); // url addURLContent(buffer, item.getURL()); endDefinitionList(buffer); endPage(buffer); return buffer.toString(); } public static void addGuessContent(StringBuffer buffer, Boolean guess) { if (guess != null) { addDefinitionListItem(buffer, "Guess?", guess.toString()); } } public static void addReturnTypeContent(StringBuffer buffer, String returnType) { if (!StringUtils.isEmpty(returnType)) { buffer.append("<dt><b>Returns:</b></dt>"); buffer.append("<dd>"); buffer.append("<code>"); buffer.append(returnType); buffer.append("</code>"); buffer.append("</dd>"); } } public static void addParametersContent(StringBuffer buffer, List<Parameter> parameters) { if (parameters != null) { buffer.append("<dt><b>Parameters:</b></dt>"); for (Parameter parameter : parameters) { buffer.append("<dd>"); if (!parameter.isRequired()) { buffer.append("["); } buffer.append("<code>"); buffer.append(parameter.getName()); buffer.append("</code>"); if (!parameter.isRequired()) { buffer.append("]"); } buffer.append(" - "); buffer.append("<code>"); buffer.append(parameter.getType()); buffer.append("</code>"); buffer.append("</dd>"); } } } public static String getTitle(TernCompletionItem item) { String title = item.hasDisplayName() ? item.getDisplayName() : item.getSignature(); StringBuilder buffer = new StringBuilder("<b>").append(title).append("</b>"); return buffer.toString(); } public static void addDocContent(StringBuffer buffer, String doc) { buffer.append("<p>"); if (doc != null) { buffer.append(doc); } buffer.append("</p>"); } public static void endPage(StringBuffer buffer) { HTMLPrinter.insertPageProlog(buffer, 0, colorInfoForeground, colorInfoBackround, HTMLTernPrinter.getStyleSheet()); HTMLPrinter.addPageEpilog(buffer); } public static void addOriginContent(StringBuffer buffer, String origin) { addLinkContent(buffer, "Origin", new StringBuilder(HoverLocationListener.TERN_FILE_PROTOCOL).append(origin).toString(), origin); } public static void addDefinitionListItem(StringBuffer buffer, String name, String value) { if (!StringUtils.isEmpty(value)) { buffer.append("<dt><b>"); buffer.append(name); buffer.append(":</b></dt>"); buffer.append("<dd>"); buffer.append(value); buffer.append("</dd>"); } } public static void addDefinitionListItem(StringBuffer buffer, String name, Collection<String> values) { if (values != null && !values.isEmpty()) { addDefinitionListItem(buffer, name, Arrays.toString(values.toArray())); } } public static void addURLContent(StringBuffer buffer, String url) { if (!StringUtils.isEmpty(url)) { addLinkContent(buffer, "See", url, url); } } protected static void addLinkContent(StringBuffer buffer, String label, String linkHref, String linkLabel) { buffer.append("<dt><b>"); buffer.append(label); buffer.append(":</b></dt>"); buffer.append("<dd>"); buffer.append("<a href=\""); buffer.append(linkHref); buffer.append("\" >"); buffer.append(linkLabel); buffer.append("</a>"); buffer.append("</dd>"); } public static void startDefinitionList(StringBuffer buffer) { buffer.append("<dl>"); //$NON-NLS-1$ } public static void endDefinitionList(StringBuffer buffer) { buffer.append("</dl>"); //$NON-NLS-1$ } /** * Returns the Javadoc hover style sheet with the current Javadoc font from * the preferences. * * @return the updated style sheet * @since 3.4 */ private static String getStyleSheet() { if (fgStyleSheet == null) { fgStyleSheet = loadStyleSheet("/TernHoverStyleSheet.css"); //$NON-NLS-1$ } String css = fgStyleSheet; if (css != null) { FontData fontData = JFaceResources.getFontRegistry().getFontData(JFaceResources.DIALOG_FONT)[0]; css = HTMLPrinter.convertTopLevelFont(css, fontData); } return css; } /** * Loads and returns the style sheet associated with either Javadoc hover or * the view. * * @param styleSheetName * the style sheet name of either the Javadoc hover or the view * @return the style sheet, or <code>null</code> if unable to load * @since 3.4 */ private static String loadStyleSheet(String styleSheetName) { Bundle bundle = Platform.getBundle(TernUIPlugin.PLUGIN_ID); URL styleSheetURL = bundle.getEntry(styleSheetName); if (styleSheetURL == null) return null; BufferedReader reader = null; try { reader = new BufferedReader(new InputStreamReader(styleSheetURL.openStream())); StringBuffer buffer = new StringBuffer(1500); String line = reader.readLine(); while (line != null) { buffer.append(line); buffer.append('\n'); line = reader.readLine(); } FontData fontData = JFaceResources.getFontRegistry().getFontData(JFaceResources.DIALOG_FONT)[0]; return HTMLPrinter.convertTopLevelFont(buffer.toString(), fontData); } catch (IOException ex) { Trace.trace(Trace.SEVERE, "Error while loading style sheets", ex); return ""; //$NON-NLS-1$ } finally { try { if (reader != null) reader.close(); } catch (IOException e) { // ignore } } } public static void startPage(StringBuffer buf, String title, ImageDescriptor descriptor) { int imageWidth = 16; int imageHeight = 16; int labelLeft = 20; int labelTop = 2; // buf.append("<p>"); buf.append("<div style='word-wrap: break-word; position: relative; "); //$NON-NLS-1$ String imageSrcPath = getImageURL(descriptor); if (imageSrcPath != null) { buf.append("margin-left: ").append(labelLeft).append("px; "); //$NON-NLS-1$ //$NON-NLS-2$ buf.append("padding-top: ").append(labelTop).append("px; "); //$NON-NLS-1$ //$NON-NLS-2$ } buf.append("'>"); //$NON-NLS-1$ if (imageSrcPath != null) { String uri = HoverLocationListener.TERN_DEFINITION_PROTOCOL; buf.append("<a href=\""); buf.append(uri); buf.append("\" >"); StringBuffer imageStyle = new StringBuffer("border:none; position: absolute; "); //$NON-NLS-1$ imageStyle.append("width: ").append(imageWidth).append("px; "); //$NON-NLS-1$ //$NON-NLS-2$ imageStyle.append("height: ").append(imageHeight).append("px; "); //$NON-NLS-1$ //$NON-NLS-2$ imageStyle.append("left: ").append(-labelLeft - 1).append("px; "); //$NON-NLS-1$ //$NON-NLS-2$ // hack for broken transparent PNG support in IE 6, see // https://bugs.eclipse.org/bugs/show_bug.cgi?id=223900 : buf.append("<!--[if lte IE 6]><![if gte IE 5.5]>\n"); //$NON-NLS-1$ String tooltip = "alt='" + TernUIMessages.TernHover_openDeclaration + "' "; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ buf.append("<span ").append(tooltip).append("style=\"").append(imageStyle). //$NON-NLS-1$ //$NON-NLS-2$ append("filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src='").append(imageSrcPath) //$NON-NLS-1$ .append("')\"></span>\n"); //$NON-NLS-1$ buf.append("<![endif]><![endif]-->\n"); //$NON-NLS-1$ buf.append("<!--[if !IE]>-->\n"); //$NON-NLS-1$ buf.append("<img ").append(tooltip).append("style='").append(imageStyle).append("' src='") //$NON-NLS-1$//$NON-NLS-2$//$NON-NLS-3$ .append(imageSrcPath).append("'/>\n"); //$NON-NLS-1$ buf.append("<!--<![endif]-->\n"); //$NON-NLS-1$ buf.append("<!--[if gte IE 7]>\n"); //$NON-NLS-1$ buf.append("<img ").append(tooltip).append("style='").append(imageStyle).append("' src='") //$NON-NLS-1$//$NON-NLS-2$//$NON-NLS-3$ .append(imageSrcPath).append("'/>\n"); //$NON-NLS-1$ buf.append("<![endif]-->\n"); //$NON-NLS-1$ // if (element != null) { buf.append("</a>"); //$NON-NLS-1$ // } } buf.append(title); buf.append("</div>"); //$NON-NLS-1$ buf.append("<hr />"); } private static String getImageURL(ImageDescriptor descriptor) { if (descriptor == null) { return null; } String imageName = null; URL imageUrl = TernUIPlugin.getTernDescriptorManager().getImageURL(descriptor); if (imageUrl != null) { imageName = imageUrl.toExternalForm(); } return imageName; } }