001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.jsp;
029
030import org.opencms.util.CmsStringUtil;
031
032import java.util.Arrays;
033import java.util.Collections;
034import java.util.List;
035
036import javax.servlet.jsp.PageContext;
037import javax.servlet.jsp.tagext.BodyTagSupport;
038
039/**
040 * Parent for body tags that require support for setting scoped variables to the JSP page context.<p>
041 *
042 * @since 7.0.2
043 */
044public class CmsJspScopedVarBodyTagSuport extends BodyTagSupport {
045
046    /** The scopes supported by the page context. */
047    private static final String[] SCOPES = {"page", "request", "session", "application"};
048
049    /** The scopes supported by the page context as a list. */
050    private static final List<String> SCOPES_LIST = Collections.unmodifiableList(Arrays.asList(SCOPES));
051
052    /** Serial version UID required for safe serialization. */
053    private static final long serialVersionUID = 6521418315921327927L;
054
055    /** The scope under which the content info is saved in the page context. */
056    private int m_scope = PageContext.PAGE_SCOPE;
057
058    /** The name of the variable under which the content info bean should be saved in the page context. */
059    private String m_variable;
060
061    /**
062     * Returns the int value of the specified scope string.<p>
063     *
064     * The default value is {@link PageContext#PAGE_SCOPE}.<p>
065     *
066     * @param scope the string name of the desired scope, e.g. "application", "request"
067     * @return the int value of the specified scope string
068     */
069    protected static int getScopeAsInt(String scope) {
070
071        int scopeValue;
072        switch (SCOPES_LIST.indexOf(scope)) {
073            case 3:
074                // application
075                scopeValue = PageContext.APPLICATION_SCOPE;
076                break;
077            case 2:
078                // session
079                scopeValue = PageContext.SESSION_SCOPE;
080                break;
081            case 1:
082                // request
083                scopeValue = PageContext.REQUEST_SCOPE;
084                break;
085            default:
086                // page
087                scopeValue = PageContext.PAGE_SCOPE;
088                break;
089        }
090        return scopeValue;
091    }
092
093    /**
094     * Returns the String value of the specified scope integer.<p>
095     *
096     * Valid values for the scope int parameter are 1 to 4 only.<p>
097     *
098     * @param scope integer that describes the scope according to {@link #getScopeInt()}.<p>
099     *
100     * @return the String value of the specified scope integer
101     */
102    protected static String getScopeAsString(int scope) {
103
104        if ((scope <= 0) || (scope > 4)) {
105            // return default scope if int is outside valid rage
106            return SCOPES[0];
107        }
108        return SCOPES[scope - 1];
109    }
110
111    /**
112     * Returns the scope under which the content access bean is saved in the page context.<p>
113     *
114     * @return the scope under which the content access bean is saved in the page context
115     */
116    public String getScope() {
117
118        return getScopeAsString(m_scope);
119    }
120
121    /**
122     * Returns the name of the variable under which the content access bean is saved in the page context.<p>
123     *
124     * @return the name of the variable under which the content access bean is saved in the page context
125     */
126    public String getVar() {
127
128        return m_variable;
129    }
130
131    /**
132     * @see javax.servlet.jsp.tagext.Tag#release()
133     */
134    @Override
135    public void release() {
136
137        m_variable = null;
138        m_scope = PageContext.PAGE_SCOPE;
139        super.release();
140    }
141
142    /**
143     * Sets the scope under which the content access bean is saved in the page context.<p>
144     *
145     * @param scope the scope under which the content access bean is saved in the page context
146     */
147    public void setScope(String scope) {
148
149        if (CmsStringUtil.isNotEmpty(scope)) {
150            scope = scope.trim().toLowerCase();
151            m_scope = getScopeAsInt(scope);
152        } else {
153            // empty scope, use default "page" scope
154            m_scope = PageContext.PAGE_SCOPE;
155        }
156    }
157
158    /**
159     * Sets the name of the variable under which the content access bean is saved in the page context.<p>
160     *
161     * @param var the name of the variable under which the content access bean is saved in the page context
162     */
163    public void setVar(String var) {
164
165        if (CmsStringUtil.isNotEmptyOrWhitespaceOnly(var)) {
166            m_variable = var.trim();
167        }
168    }
169
170    /**
171     * Returns the scope as int usable for setting the JSP page context
172     * with {@link PageContext#setAttribute(String, Object, int)}.<p>
173     *
174     * @return the scope as int usable for setting the JSP page context
175     */
176    protected int getScopeInt() {
177
178        return m_scope;
179    }
180
181    /**
182     * Returns <code>true</code> in case the scoped variable has been set for this Tag.<p>
183     *
184     * @return <code>true</code> in case the scoped variable has been set for this Tag
185     */
186    protected boolean isScopeVarSet() {
187
188        return CmsStringUtil.isNotEmpty(getVar());
189    }
190
191    /**
192     * Stores the provided Object as attribute in the JSP page context.<p>
193     *
194     * The values of {@link  #getVar()} and {@link #getScope()} are used to determine how the Object is stored.<p>
195     *
196     * @param obj the Object to store in the JSP page context
197     */
198    protected void storeAttribute(Object obj) {
199
200        storeAttribute(getVar(), obj);
201    }
202
203    /**
204     * Stores the provided Object as attribute with the provided name in the JSP page context.<p>
205     *
206     * The value of {@link #getScope()} is used to determine how the Object is stored.<p>
207     *
208     * @param name the name of the attribute to store the Object in
209     * @param obj the Object to store in the JSP page context
210     */
211    protected void storeAttribute(String name, Object obj) {
212
213        pageContext.setAttribute(name, obj, getScopeInt());
214    }
215}