src/org/jsecurity/web/servlet/ServletContextSupport.java

/*
 * Copyright 2005-2008 Les Hazlewood
 *
 * 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 org.jsecurity.web.servlet;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jsecurity.web.DefaultWebSecurityManager;

import javax.servlet.ServletContext;

/**
 * TODO - class javadoc
 *
 * @author Les Hazlewood
 * @since 0.2
 */
public class ServletContextSupport {

    public static final String SESSION_MODE_CONTEXT_PARAM_NAME = "sessionMode";
    public static final String HTTP_SESSION_MODE = DefaultWebSecurityManager.HTTP_SESSION_MODE;
    public static final String JSECURITY_SESSION_MODE = DefaultWebSecurityManager.JSECURITY_SESSION_MODE;

    protected transient final Log log = LogFactory.getLog( getClass() );

    private ServletContext servletContext = null;
    private String sessionMode = null;

    public ServletContext getServletContext() {
        return servletContext;
    }

    public void setServletContext(ServletContext servletContext) {
        this.servletContext = servletContext;
    }

    protected String getContextInitParam(String paramName) {
        return getServletContext().getInitParameter(paramName);
    }

    private ServletContext getServletContextNullCheck() {
        ServletContext servletContext = getServletContext();
        if (servletContext == null) {
            String msg = "ServletContext property must be set via the setServletContext method.";
            throw new IllegalStateException(msg);
        }
        return servletContext;
    }

    protected void setAttribute( String key, Object value ) {
        getServletContextNullCheck().setAttribute( key, value );
    }

    protected Object getAttribute( String key ) {
        return getServletContextNullCheck().getAttribute( key );
    }

    protected void removeAttribute( String key ) {
        getServletContextNullCheck().removeAttribute( key );
    }

    protected void bind(String name, String key, Object value) {
        if (value == null) {
            throw new IllegalArgumentException(name + " argument cannot be null.");
        }
        if (getAttribute(key) != null) {
            String msg = name + " already bound to ServletContext.  Please check your configuration to ensure " +
                    "you don't have mutliple SecurityManager Loaders configured (listener, servlet, etc).";
            throw new IllegalStateException(msg);
        }
        setAttribute(key, value);
    }

    public String getSessionMode() {
        return sessionMode;
    }

    public void setSessionMode(String mode) {
        if (mode != null) {
            mode = mode.trim().toLowerCase();
            if (!mode.equals(HTTP_SESSION_MODE) && !mode.equals(JSECURITY_SESSION_MODE)) {
                String msg = "Unknown '" + SESSION_MODE_CONTEXT_PARAM_NAME + "' value [" +
                    mode + "].  Recognized values are '" +
                        HTTP_SESSION_MODE + "' and '" + JSECURITY_SESSION_MODE +
                    "' (without quotes).  Please check your configuration and/or spelling.";
                throw new IllegalArgumentException(msg);
            }
            this.sessionMode = mode;
        }
    }

    protected void applySessionMode() {
        setSessionMode( getContextInitParam(SESSION_MODE_CONTEXT_PARAM_NAME) );
    }

    protected boolean isHttpSessions() {
        String sessionMode = getSessionMode();
        return sessionMode == null || sessionMode.equals(HTTP_SESSION_MODE);
    }
}