/** * $RCSfile: ParamUtils.java,v $ * $Revision: 1.1 $ * $Date: 2002/06/20 15:58:05 $ * * Copyright (C) 1999-2001 CoolServlets, Inc. All rights reserved. * * This software is the proprietary information of CoolServlets, Inc. * Use is subject to license terms. */package com.struts2.framework.util;import javax.servlet.http.HttpServletRequest;/** * This class assists skin writers in getting parameters. */public class ParamUtils {    /**     * Gets a parameter as a string.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @return The value of the parameter or null if the parameter was not     *      found or if the parameter is a zero-length string.     */    public static String getParameter(HttpServletRequest request, String name) {        return getParameter(request, name, false);    }    /**     * Gets a parameter as a string.     * @param request The HttpServletRequest object, known as "request" in a     * JSP page.     * @param name The name of the parameter you want to get     * @param emptyStringsOK Return the parameter values even if it is an empty string.     * @return The value of the parameter or null if the parameter was not     *      found.     */    public static String getParameter(HttpServletRequest request,            String name, boolean emptyStringsOK)    {        String temp = request.getParameter(name);        if (temp != null) {            if (temp.equals("") && !emptyStringsOK) {                return null;            }            else {                return temp;            }        }        else {            return null;        }    }    /**     * Returns a list of parameters of the same name     *     * @param request an HttpServletRequest object.     * @return an array of non-null, non-blank strings of the same name. This     * method will return an empty array if no parameters were found.     */    public static String[] getParameters(HttpServletRequest request, String name)    {        if (name == null) {            return new String[0];        }        String[] paramValues = request.getParameterValues(name);        if (paramValues == null || paramValues.length == 0) {            return new String[0];        }        else {            java.util.List values = new java.util.ArrayList(paramValues.length);            for (int i=0; i<paramValues.length; i++) {                if (paramValues[i] != null && !"".equals(paramValues[i])) {                    values.add(paramValues[i]);                }            }            return (String[])values.toArray(new String[]{});        }    }    /**     * Gets a parameter as a boolean.     * @param request The HttpServletRequest object, known as "request" in a     * JSP page.     * @param name The name of the parameter you want to get     * @return True if the value of the parameter was "true", false otherwise.     */    public static boolean getBooleanParameter(HttpServletRequest request,            String name)    {        return getBooleanParameter(request, name, false);    }    /**     * Gets a parameter as a boolean.     * @param request The HttpServletRequest object, known as "request" in a     * JSP page.     * @param name The name of the parameter you want to get     * @return True if the value of the parameter was "true", false otherwise.     */    public static boolean getBooleanParameter(HttpServletRequest request,            String name, boolean defaultVal)    {        String temp = request.getParameter(name);        if ("true".equals(temp) || "on".equals(temp)) {            return true;        }        else if ("false".equals(temp) || "off".equals(temp)) {            return false;        }        else {            return defaultVal;        }    }    /**     * Gets a parameter as an int.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @return The int value of the parameter specified or the default value if     *      the parameter is not found.     */    public static int getIntParameter(HttpServletRequest request,            String name, int defaultNum)    {        String temp = request.getParameter(name);        if(temp != null && !temp.equals("")) {            int num = defaultNum;            try {                num = Integer.parseInt(temp);            }            catch (Exception ignored) {}            return num;        }        else {            return defaultNum;        }    }    /**     * Gets a list of int parameters.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @param defaultNum The default value of a parameter, if the parameter     * can't be converted into an int.     */    public static int[] getIntParameters(HttpServletRequest request,            String name, int defaultNum)    {        String[] paramValues = request.getParameterValues(name);        if (paramValues == null || paramValues.length == 0) {            return new int[0];        }        int[] values = new int[paramValues.length];        for (int i=0; i<paramValues.length; i++) {            try {                values[i] = Integer.parseInt(paramValues[i]);            }            catch (Exception e) {                values[i] = defaultNum;            }        }        return values;    }    /**     * Gets a parameter as a double.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @return The double value of the parameter specified or the default value     *      if the parameter is not found.     */    public static double getDoubleParameter(HttpServletRequest request,            String name, double defaultNum)    {        String temp = request.getParameter(name);        if(temp != null && !temp.equals("")) {            double num = defaultNum;            try {                num = Double.parseDouble(temp);            }            catch (Exception ignored) {}            return num;        }        else {            return defaultNum;        }    }    /**     * Gets a parameter as a long.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @return The long value of the parameter specified or the default value if     *      the parameter is not found.     */    public static long getLongParameter(HttpServletRequest request,            String name, long defaultNum)    {        String temp = request.getParameter(name);        if (temp != null && !temp.equals("")) {            long num = defaultNum;            try {                num = Long.parseLong(temp);            }            catch (Exception ignored) {}            return num;        }        else {            return defaultNum;        }    }    /**     * Gets a list of long parameters.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @param defaultNum The default value of a parameter, if the parameter     * can't be converted into a long.     */    public static long[] getLongParameters(HttpServletRequest request,            String name, long defaultNum)    {        String[] paramValues = request.getParameterValues(name);        if (paramValues == null || paramValues.length == 0) {            return new long[0];        }        long[] values = new long[paramValues.length];        for (int i=0; i<paramValues.length; i++) {            try {                values[i] = Long.parseLong(paramValues[i]);            }            catch (Exception e) {                values[i] = defaultNum;            }        }        return values;    }    /**     * Gets a parameter as a string.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @return The value of the parameter or null if the parameter was not     *      found or if the parameter is a zero-length string.     */    public static String getAttribute(HttpServletRequest request, String name) {        return getAttribute (request, name, false);    }    /**     * Gets a parameter as a string.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the parameter you want to get     * @param emptyStringsOK Return the parameter values even if it is an empty string.     * @return The value of the parameter or null if the parameter was not     *      found.     */    public static String getAttribute(HttpServletRequest request,            String name, boolean emptyStringsOK)    {        String temp = (String)request.getAttribute(name);        if (temp != null) {            if (temp.equals("") && !emptyStringsOK) {                return null;            }            else {                return temp;            }        }        else {            return null;        }    }    /**     * Gets an attribute as a boolean.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the attribute you want to get     * @return True if the value of the attribute is "true", false otherwise.     */    public static boolean getBooleanAttribute(HttpServletRequest request,            String name)    {        String temp = (String)request.getAttribute(name);        if (temp != null && temp.equals("true")) {            return true;        }        else {            return false;        }    }    /**     * Gets an attribute as a int.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the attribute you want to get     * @return The int value of the attribute or the default value if the     *      attribute is not found or is a zero length string.     */    public static int getIntAttribute(HttpServletRequest request,            String name, int defaultNum)    {        String temp = (String)request.getAttribute(name);        if (temp != null && !temp.equals("")) {            int num = defaultNum;            try {                num = Integer.parseInt(temp);            }            catch (Exception ignored) {}            return num;        }        else {            return defaultNum;        }    }    /**     * Gets an attribute as a long.     * @param request The HttpServletRequest object, known as "request" in a     *      JSP page.     * @param name The name of the attribute you want to get     * @return The long value of the attribute or the default value if the     *      attribute is not found or is a zero length string.     */    public static long getLongAttribute(HttpServletRequest request,            String name, long defaultNum)    {        String temp = (String)request.getAttribute(name);        if (temp != null && !temp.equals("")) {            long num = defaultNum;            try {                num = Long.parseLong(temp);            }            catch (Exception ignored) {}            return num;        }        else {            return defaultNum;        }     }}