Java tutorial
/** * Copyright (c) 2013-2014 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 org.eclipse.wst.json.ui.internal.text.hover; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URL; 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.json.jsonpath.IJSONPath; import org.eclipse.json.schema.IJSONSchemaDocument; import org.eclipse.json.schema.IJSONSchemaProperty; import org.eclipse.swt.graphics.FontData; import org.eclipse.wst.json.core.JSONCorePlugin; import org.eclipse.wst.json.core.document.IJSONNode; import org.eclipse.wst.json.core.document.IJSONPair; import org.eclipse.wst.json.core.document.IJSONValue; import org.eclipse.wst.json.ui.internal.JSONUIPlugin; import org.eclipse.wst.json.ui.internal.Logger; import org.eclipse.wst.json.ui.internal.editor.JSONEditorPluginImageHelper; import org.osgi.framework.Bundle; /** * Provides a set of convenience methods for creating HTML info for JSON content * assist and hover. * */ public class HTMLJSONPrinter { /** * Style sheets content. */ private static String fgStyleSheet; public static String getAdditionalProposalInfo(IJSONPair pair) { StringBuffer buffer = new StringBuffer(); ImageDescriptor descriptor = null; IJSONValue value = pair.getValue(); if (value != null) { descriptor = JSONEditorPluginImageHelper.getInstance().getImageDescriptor(value.getNodeType()); } startPage(buffer, getTitleKey(value), descriptor); startDefinitionList(buffer); StringBuffer buff = new StringBuffer(); buff.append(pair.getName()); try { IJSONSchemaDocument schemaDocument = JSONCorePlugin.getDefault().getSchemaDocument(pair); if (schemaDocument != null) { IJSONPath path = pair.getPath(); IJSONSchemaProperty property = schemaDocument.getProperty(path); if (property != null) { String description = property.getDescription(); if (description != null) { buff.append(" - "); buff.append(description); } } } } catch (IOException e) { Logger.logException(e); } addDefinitionListItem(buffer, "Key", buff.toString()); addDefinitionListItem(buffer, "Type", getValueType(pair.getValue())); endDefinitionList(buffer); endPage(buffer); return buffer.toString(); } private static String getTitleKey(IJSONValue value) { return new StringBuilder("<b>JSON ").append(getValueType(value)).append("</b>").toString(); } private static String getValueType(IJSONValue value) { if (value == null) { return "?"; } switch (value.getNodeType()) { case IJSONNode.ARRAY_NODE: return "Array"; case IJSONNode.DOCUMENT_NODE: return "Document"; case IJSONNode.OBJECT_NODE: return "Object"; case IJSONNode.VALUE_BOOLEAN_NODE: return "Boolean"; case IJSONNode.VALUE_NULL_NODE: return "Null"; case IJSONNode.VALUE_NUMBER_NODE: return "Number"; case IJSONNode.VALUE_STRING_NODE: return "String"; } return "?"; } public static String getAdditionalProposalInfo(IJSONValue value) { StringBuffer buffer = new StringBuffer(); ImageDescriptor descriptor = JSONEditorPluginImageHelper.getInstance() .getImageDescriptor(value.getNodeType()); startPage(buffer, "<b>JSON Value</b>", descriptor); startDefinitionList(buffer); addDefinitionListItem(buffer, "Value", value.getSimpleValue()); addDefinitionListItem(buffer, "Type", getValueType(value)); endDefinitionList(buffer); endPage(buffer); return buffer.toString(); } private static String getTitle(IJSONValue value) { StringBuilder title = new StringBuilder("<b>"); title.append(getValueType(value)); title.append("</b>"); return title.toString(); } public static void startDefinitionList(StringBuffer buffer) { buffer.append("<dl>"); //$NON-NLS-1$ } public static void endDefinitionList(StringBuffer buffer) { buffer.append("</dl>"); //$NON-NLS-1$ } public static void addDefinitionListItem(StringBuffer buffer, String name, String value) { if (value != null) { buffer.append("<dt><b>"); buffer.append(name); buffer.append(":</b></dt>"); buffer.append("<dd>"); buffer.append(value); buffer.append("</dd>"); } } /** * Returns the Javadoc hover style sheet with the current JSON font from the * preferences. * * @return the updated style sheet */ private static String getStyleSheet() { if (fgStyleSheet == null) { fgStyleSheet = loadStyleSheet("/JSONHoverStyleSheet.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 JSON 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 */ private static String loadStyleSheet(String styleSheetName) { Bundle bundle = Platform.getBundle(JSONUIPlugin.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) { Logger.logException("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='" + "" + "' "; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ 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 = JSONEditorPluginImageHelper.getInstance().getImageURL(descriptor); if (imageUrl != null) { imageName = imageUrl.toExternalForm(); } return imageName; } public static void endPage(StringBuffer buffer) { HTMLPrinter.insertPageProlog(buffer, 0, HTMLJSONPrinter.getStyleSheet()); HTMLPrinter.addPageEpilog(buffer); } }