/** * Licensed under the Artistic License; you may not use this file * except in compliance with the License. * You may obtain a copy of the License at * *      http://displaytag.sourceforge.net/license.html * * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */package org.displaytag.tags;import java.util.ArrayList;import java.util.Arrays;import java.util.List;import javax.servlet.jsp.tagext.TagAttributeInfo;import javax.servlet.jsp.tagext.TagData;import javax.servlet.jsp.tagext.TagExtraInfo;import javax.servlet.jsp.tagext.VariableInfo;/** * TEI for TableTag, defines 3 variables. * <ul> * <li>table uid = object contained in row</li> * <li>table uid + ROWNUM_SUFFIX = row number</li> * </ul> * @author Fabrizio Giustina * @version $Revision: 1081 $ ($Author: fgiust $) */public class TableTagExtraInfo extends TagExtraInfo{    /**     * Suffix added to id for saving row number in pagecontext.     */    public static final String ROWNUM_SUFFIX = "_rowNum"; //$NON-NLS-1$    /**     * Java keywords.     */    private static final String[] KEYWORDS = {"abstract", //$NON-NLS-1$        "assert", //$NON-NLS-1$        "boolean", //$NON-NLS-1$        "break", //$NON-NLS-1$        "byte", //$NON-NLS-1$        "case", //$NON-NLS-1$        "catch", //$NON-NLS-1$        "char", //$NON-NLS-1$        "class", //$NON-NLS-1$        "const", //$NON-NLS-1$        "continue", //$NON-NLS-1$        "default", //$NON-NLS-1$        "do", //$NON-NLS-1$        "double", //$NON-NLS-1$        "else", //$NON-NLS-1$        "enum", //$NON-NLS-1$        "extends", //$NON-NLS-1$        "false", //$NON-NLS-1$        "final", //$NON-NLS-1$        "finally", //$NON-NLS-1$        "float", //$NON-NLS-1$        "for", //$NON-NLS-1$        "goto", //$NON-NLS-1$        "if", //$NON-NLS-1$        "implements", //$NON-NLS-1$        "import", //$NON-NLS-1$        "instanceof", //$NON-NLS-1$        "int", //$NON-NLS-1$        "interface", //$NON-NLS-1$        "long", //$NON-NLS-1$        "native", //$NON-NLS-1$        "new", //$NON-NLS-1$        "null", //$NON-NLS-1$        "package", //$NON-NLS-1$        "private", //$NON-NLS-1$        "protected", //$NON-NLS-1$        "public", //$NON-NLS-1$        "return", //$NON-NLS-1$        "short", //$NON-NLS-1$        "static", //$NON-NLS-1$        "strictfp", //$NON-NLS-1$        "super", //$NON-NLS-1$        "switch", //$NON-NLS-1$        "synchronized", //$NON-NLS-1$        "this", //$NON-NLS-1$        "throw", //$NON-NLS-1$        "throws", //$NON-NLS-1$        "transient", //$NON-NLS-1$        "true", //$NON-NLS-1$        "try", //$NON-NLS-1$        "void", //$NON-NLS-1$        "volatile", //$NON-NLS-1$        "while"}; //$NON-NLS-1$    /**     * Variables TableTag makes available in the pageContext.     * @param data TagData     * @return VariableInfo[]     * @see javax.servlet.jsp.tagext.TagData     * @see javax.servlet.jsp.tagext.VariableInfo     */    public VariableInfo[] getVariableInfo(TagData data)    {        List variables = new ArrayList(2);        Object idObj = data.getAttribute(TagAttributeInfo.ID);        // handle both the id and uid attributes        if (idObj == null)        {            idObj = data.getAttribute("uid"); //$NON-NLS-1$        }        // avoid errors, but "id" and "id_rownum" will not be defined        if (idObj != TagData.REQUEST_TIME_VALUE && idObj != null)        {            String tagId = idObj.toString();            // don't try to add variables if id is not a valid java identifier.            if (isJavaId(tagId))            {                // current row                variables.add(new VariableInfo(tagId, Object.class.getName(), true, VariableInfo.NESTED));                // current row number                variables.add(new VariableInfo(                    tagId + ROWNUM_SUFFIX,                    Integer.class.getName(),                    true,                    VariableInfo.NESTED));            }        }        return (VariableInfo[]) variables.toArray(new VariableInfo[]{});    }    /**     * isJavaId Returns true if the name is a valid java identifier.     * @param id to check     * @return boolean true/false     */    public static boolean isJavaId(String id)    {        if (id == null            || id.length() == 0            || Arrays.binarySearch(KEYWORDS, id) >= 0            || !Character.isJavaIdentifierStart(id.charAt(0)))        {            return false;        }        for (int j = 1; j < id.length(); j++)        {            if (!Character.isJavaIdentifierPart(id.charAt(j)))            {                return false;            }        }        return true;    }}