HTMLUtil.java

/*******************************************************************************
 * Copyright (c) 2004, 2005 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ui.internal.intro.impl.html;

import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**
 * Convenience class for generating HTML elements.
 */
public final class HTMLUtil {
    /**
     * Creates an HTML opening element of the form <elementName
     * elementAttributes>
     *
     * @param elementName
     *            the name of the element to create
     * @param elementAttributes
     *            a map of attribute names and values to be inserted into the
     *            element start tag
     * @param insertLineBreak
     *            true to insert a line break after the start tag is closed,
     *            false otherwise
     * @return
     */
    public static StringBuffer createHTMLStartTag(String elementName,
            Map elementAttributes, boolean insertLineBreak) {
        StringBuffer element = new StringBuffer();
        if (elementName != null) {
            // open the start tag
            element.append(openHTMLStartTag(elementName));
            // add the attributes, if there are any
            if (elementAttributes != null && !(elementAttributes.isEmpty()))
                element.append(IIntroHTMLConstants.SPACE).append(
                        createAttributeList(elementAttributes));
            // close the start tag
            element.append(closeHTMLTag(insertLineBreak));
        }
        return element;
    }

    /**
     * Creates an HTML start tag of the form <elementName>
     *
     * @param elementName
     *            the name of the element to create
     * @param insertLineBreak
     *            true to insert a new line after the start tag
     * @return
     */
    public static StringBuffer createHTMLStartTag(String elementName,
            boolean insertLineBreak) {
        return createHTMLStartTag(elementName, null, insertLineBreak);
    }

    /**
     * Creates an HTML start tag of the form <elementName>and inserts a line
     * break after the start tag
     *
     * @param elementName
     *            the name of the element to create
     * @return
     */
    public static StringBuffer createHTMLStartTag(String elementName) {
        return createHTMLStartTag(elementName, null, true);
    }

    /**
     * Creates an HTML closing element of the form </elementName>
     *
     * @param elementName
     *            the name of the closing element to create
     * @param addNewLine
     *            true to add a new line at the end
     * @return
     */
    public static StringBuffer createHTMLEndTag(String elementName,
            boolean addNewLine) {
        StringBuffer closingElement = new StringBuffer();
        if (elementName != null)
            closingElement.append(IIntroHTMLConstants.LT).append(
                    IIntroHTMLConstants.FORWARD_SLASH).append(elementName)
                    .append(closeHTMLTag(addNewLine));
        return closingElement;
    }

    /**
     * Given a map of attribute names and values, this method will create a
     * StringBuffer of the attributes in the form: attrName="attrValue". These
     * attributes can appear in the start tag of an HTML element.
     *
     * @param attributes
     *            the attributes to be converted into a String list
     * @return
     */
    public static String createAttributeList(Map attributes) {
        if (attributes == null)
            return null;
        StringBuffer attributeList = new StringBuffer();
        Set attrNames = attributes.keySet();
        for (Iterator it = attrNames.iterator(); it.hasNext();) {
            Object name = it.next();
            Object value = attributes.get(name);
            if ((name instanceof String) && (value instanceof String)) {
                attributeList.append(createAttribute((String) name,
                        (String) value));
                if (it.hasNext()) {
                    attributeList.append(IIntroHTMLConstants.SPACE);
                }
            }
        }
        return attributeList.toString();
    }

    /**
     * Creates an HTML attribute of the form attrName="attrValue"
     *
     * @param attrName
     *            the name of the attribute
     * @param attrValue
     *            the value of the attribute
     * @return
     */
    public static StringBuffer createAttribute(String attrName, String attrValue) {
        StringBuffer attribute = new StringBuffer();
        if (attrName != null && attrValue != null) {
            attribute.append(attrName).append(IIntroHTMLConstants.EQUALS)
                    .append(IIntroHTMLConstants.QUOTE).append(attrValue)
                    .append(IIntroHTMLConstants.QUOTE);
        }
        return attribute;
    }

    public static StringBuffer openHTMLStartTag(String elementName) {
        return new StringBuffer().append(IIntroHTMLConstants.LT).append(
                elementName);
    }

    public static StringBuffer closeHTMLTag() {
        return closeHTMLTag(true);
    }

    public static StringBuffer closeHTMLTag(boolean newLine) {
        StringBuffer closing = new StringBuffer()
                .append(IIntroHTMLConstants.GT);
        if (newLine)
            closing.append(IIntroHTMLConstants.NEW_LINE);
        return closing;
    }

    /**
     * Determine if the contents of two character arrays are equal
     *
     * @param a
     * @param b
     * @return
     */
    public static boolean equalCharArrayContent(char[] a, char[] b) {
        if (a.length != b.length)
            return false;
        for (int i = 0; i < a.length; i++) {
            if (a[i] != b[i])
                return false;
        }
        return true;
    }
}