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/* * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved. * Copyright 2004 The Apache Software Foundation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package javax.servlet.jsp.jstl.core; import javax.servlet.ServletContext; import javax.servlet.ServletRequest; import javax.servlet.http.HttpSession; import javax.servlet.jsp.PageContext; /** * Class supporting access to configuration settings. */ public class Config { /* * I18N/Formatting actions related configuration data */ /** * Name of configuration setting for application- (as opposed to browser-) * based preferred locale */ public static final String FMT_LOCALE = "javax.servlet.jsp.jstl.fmt.locale"; /** * Name of configuration setting for fallback locale */ public static final String FMT_FALLBACK_LOCALE = "javax.servlet.jsp.jstl.fmt.fallbackLocale"; /** * Name of configuration setting for i18n localization context */ public static final String FMT_LOCALIZATION_CONTEXT = "javax.servlet.jsp.jstl.fmt.localizationContext"; /** * Name of localization setting for time zone */ public static final String FMT_TIME_ZONE = "javax.servlet.jsp.jstl.fmt.timeZone"; /* * SQL actions related configuration data */ /** * Name of configuration setting for SQL data source */ public static final String SQL_DATA_SOURCE = "javax.servlet.jsp.jstl.sql.dataSource"; /** * Name of configuration setting for maximum number of rows to be included * in SQL query result */ public static final String SQL_MAX_ROWS = "javax.servlet.jsp.jstl.sql.maxRows"; /* * Private constants */ private static final String PAGE_SCOPE_SUFFIX = ".page"; private static final String REQUEST_SCOPE_SUFFIX = ".request"; private static final String SESSION_SCOPE_SUFFIX = ".session"; private static final String APPLICATION_SCOPE_SUFFIX = ".application"; /** * Looks up a configuration variable in the given scope. * * <p> The lookup of configuration variables is performed as if each scope * had its own name space, that is, the same configuration variable name * in one scope does not replace one stored in a different scope. * * @param pc Page context in which the configuration variable is to be * looked up * @param name Configuration variable name * @param scope Scope in which the configuration variable is to be looked * up * * @return The <tt>java.lang.Object</tt> associated with the configuration * variable, or null if it is not defined. */ public static Object get(PageContext pc, String name, int scope) { switch (scope) { case PageContext.PAGE_SCOPE: return pc.getAttribute(name + PAGE_SCOPE_SUFFIX, scope); case PageContext.REQUEST_SCOPE: return pc.getAttribute(name + REQUEST_SCOPE_SUFFIX, scope); case PageContext.SESSION_SCOPE: return get(pc.getSession(), name); case PageContext.APPLICATION_SCOPE: return pc.getAttribute(name + APPLICATION_SCOPE_SUFFIX, scope); default: throw new IllegalArgumentException("unknown scope"); } } /** * Looks up a configuration variable in the "request" scope. * * <p> The lookup of configuration variables is performed as if each scope * had its own name space, that is, the same configuration variable name * in one scope does not replace one stored in a different scope. * * @param request Request object in which the configuration variable is to * be looked up * @param name Configuration variable name * * @return The <tt>java.lang.Object</tt> associated with the configuration * variable, or null if it is not defined. */ public static Object get(ServletRequest request, String name) { return request.getAttribute(name + REQUEST_SCOPE_SUFFIX); } /** * Looks up a configuration variable in the "session" scope. * * <p> The lookup of configuration variables is performed as if each scope * had its own name space, that is, the same configuration variable name * in one scope does not replace one stored in a different scope.</p> * * @param session Session object in which the configuration variable is to * be looked up * @param name Configuration variable name * * @return The <tt>java.lang.Object</tt> associated with the configuration * variable, or null if it is not defined, if session is null, or if the session * is invalidated. */ public static Object get(HttpSession session, String name) { Object ret = null; if (session != null) { try { ret = session.getAttribute(name + SESSION_SCOPE_SUFFIX); } catch (IllegalStateException ex) { } // when session is invalidated } return ret; } /** * Looks up a configuration variable in the "application" scope. * * <p> The lookup of configuration variables is performed as if each scope * had its own name space, that is, the same configuration variable name * in one scope does not replace one stored in a different scope. * * @param context Servlet context in which the configuration variable is * to be looked up * @param name Configuration variable name * * @return The <tt>java.lang.Object</tt> associated with the configuration * variable, or null if it is not defined. */ public static Object get(ServletContext context, String name) { return context.getAttribute(name + APPLICATION_SCOPE_SUFFIX); } /** * Sets the value of a configuration variable in the given scope. * * <p> Setting the value of a configuration variable is performed as if * each scope had its own namespace, that is, the same configuration * variable name in one scope does not replace one stored in a different * scope. * * @param pc Page context in which the configuration variable is to be set * @param name Configuration variable name * @param value Configuration variable value * @param scope Scope in which the configuration variable is to be set */ public static void set(PageContext pc, String name, Object value, int scope) { switch (scope) { case PageContext.PAGE_SCOPE: pc.setAttribute(name + PAGE_SCOPE_SUFFIX, value, scope); break; case PageContext.REQUEST_SCOPE: pc.setAttribute(name + REQUEST_SCOPE_SUFFIX, value, scope); break; case PageContext.SESSION_SCOPE: pc.setAttribute(name + SESSION_SCOPE_SUFFIX, value, scope); break; case PageContext.APPLICATION_SCOPE: pc.setAttribute(name + APPLICATION_SCOPE_SUFFIX, value, scope); break; default: throw new IllegalArgumentException("unknown scope"); } } /** * Sets the value of a configuration variable in the "request" scope. * * <p> Setting the value of a configuration variable is performed as if * each scope had its own namespace, that is, the same configuration * variable name in one scope does not replace one stored in a different * scope. * * @param request Request object in which the configuration variable is to * be set * @param name Configuration variable name * @param value Configuration variable value */ public static void set(ServletRequest request, String name, Object value) { request.setAttribute(name + REQUEST_SCOPE_SUFFIX, value); } /** * Sets the value of a configuration variable in the "session" scope. * * <p> Setting the value of a configuration variable is performed as if * each scope had its own namespace, that is, the same configuration * variable name in one scope does not replace one stored in a different * scope. * * @param session Session object in which the configuration variable is to * be set * @param name Configuration variable name * @param value Configuration variable value */ public static void set(HttpSession session, String name, Object value) { session.setAttribute(name + SESSION_SCOPE_SUFFIX, value); } /** * Sets the value of a configuration variable in the "application" scope. * * <p> Setting the value of a configuration variable is performed as if * each scope had its own namespace, that is, the same configuration * variable name in one scope does not replace one stored in a different * scope. * * @param context Servlet context in which the configuration variable is to * be set * @param name Configuration variable name * @param value Configuration variable value */ public static void set(ServletContext context, String name, Object value) { context.setAttribute(name + APPLICATION_SCOPE_SUFFIX, value); } /** * Removes a configuration variable from the given scope. * * <p> Removing a configuration variable is performed as if each scope had * its own namespace, that is, the same configuration variable name in one * scope does not impact one stored in a different scope. * * @param pc Page context from which the configuration variable is to be * removed * @param name Configuration variable name * @param scope Scope from which the configuration variable is to be * removed */ public static void remove(PageContext pc, String name, int scope) { switch (scope) { case PageContext.PAGE_SCOPE: pc.removeAttribute(name + PAGE_SCOPE_SUFFIX, scope); break; case PageContext.REQUEST_SCOPE: pc.removeAttribute(name + REQUEST_SCOPE_SUFFIX, scope); break; case PageContext.SESSION_SCOPE: pc.removeAttribute(name + SESSION_SCOPE_SUFFIX, scope); break; case PageContext.APPLICATION_SCOPE: pc.removeAttribute(name + APPLICATION_SCOPE_SUFFIX, scope); break; default: throw new IllegalArgumentException("unknown scope"); } } /** * Removes a configuration variable from the "request" scope. * * <p> Removing a configuration variable is performed as if each scope had * its own namespace, that is, the same configuration variable name in one * scope does not impact one stored in a different scope. * * @param request Request object from which the configuration variable is * to be removed * @param name Configuration variable name */ public static void remove(ServletRequest request, String name) { request.removeAttribute(name + REQUEST_SCOPE_SUFFIX); } /** * Removes a configuration variable from the "session" scope. * * <p> Removing a configuration variable is performed as if each scope had * its own namespace, that is, the same configuration variable name in one * scope does not impact one stored in a different scope. * * @param session Session object from which the configuration variable is * to be removed * @param name Configuration variable name */ public static void remove(HttpSession session, String name) { session.removeAttribute(name + SESSION_SCOPE_SUFFIX); } /** * Removes a configuration variable from the "application" scope. * * <p> Removing a configuration variable is performed as if each scope had * its own namespace, that is, the same configuration variable name in one * scope does not impact one stored in a different scope. * * @param context Servlet context from which the configuration variable is * to be removed * @param name Configuration variable name */ public static void remove(ServletContext context, String name) { context.removeAttribute(name + APPLICATION_SCOPE_SUFFIX); } /** * Finds the value associated with a specific configuration setting * identified by its context initialization parameter name. * * <p> For each of the JSP scopes (page, request, session, application), * get the value of the configuration variable identified by <tt>name</tt> * using method <tt>get()</tt>. Return as soon as a non-null value is * found. If no value is found, get the value of the context initialization * parameter identified by <tt>name</tt>. * * @param pc Page context in which the configuration setting is to be * searched * @param name Context initialization parameter name of the configuration * setting * * @return The <tt>java.lang.Object</tt> associated with the configuration * setting identified by <tt>name</tt>, or null if it is not defined. */ public static Object find(PageContext pc, String name) { Object ret = get(pc, name, PageContext.PAGE_SCOPE); if (ret == null) { ret = get(pc, name, PageContext.REQUEST_SCOPE); if (ret == null) { if (pc.getSession() != null) { // check session only if a session is present ret = get(pc, name, PageContext.SESSION_SCOPE); } if (ret == null) { ret = get(pc, name, PageContext.APPLICATION_SCOPE); if (ret == null) { ret = pc.getServletContext().getInitParameter(name); } } } } return ret; } }