parameterregistry.java

exTreme taglib的使用

/*
 * Copyright 2004 original author or authors.
 *
 * 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.extremecomponents.table.core;

import java.net.URLEncoder;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.PageContext;

import org.apache.commons.lang.StringUtils;
import org.extremecomponents.table.bean.Table;

/**
 * 
 * @author jeff johnston
 */
public final class ParameterRegistry {
    private BaseModel model;
    private Map parameters = new HashMap();

    public ParameterRegistry(BaseModel model) {
        this.model = model;
    }

    public void init(PageContext pageContext) {
        if (shouldUseSessionFilterSort() && saveFilterSort()) {
            this.parameters = getParameters();
        } else {
            Enumeration enumeration = pageContext.getRequest().getParameterNames();
            while (enumeration.hasMoreElements()) {
                String name = (String) enumeration.nextElement();
                String value = pageContext.getRequest().getParameter(name);

                if (StringUtils.isNotBlank(value)) {
                    value = value.trim();
                }

                if (name.startsWith(model.getTableHandler().prefixWithTableId() + TableConstants.PAGE)
                        || name.startsWith(model.getTableHandler().prefixWithTableId()
                                + TableConstants.CURRENT_ROWS_DISPLAYED)
                        || name.startsWith(model.getTableHandler().prefixWithTableId() + TableConstants.SORT)
                        || name.startsWith(model.getTableHandler().prefixWithTableId() + TableConstants.FILTER)
                        || name.startsWith(model.getTableHandler().prefixWithTableId() + TableConstants.EXPORT)
                        || name.startsWith(model.getTableHandler().prefixWithTableId() + TableConstants.OPEN)) {
                    parameters.put(name, value);
                } else {
                    if (model.getTableHandler().getTable().autoIncludeParameters()) {
                        if (!name.equals(Table.EXTREME_TABLE)) {
                            parameters.put(name, value);
                        }
                    }
                }
            }
        }

        if (saveFilterSort()) {
            saveParametersInSession();
        }
    }

    /**
     * Add additional parameters that need to be passed around
     */
    public void addParameter(String name, String value) {
        if (StringUtils.isNotBlank(value)) {
            value = value.trim();
        }

        parameters.put(name, value);
    }

    /**
     * Get the parameter prepended by the table key
     */
    public String getParameter(String parameter) {
        return (String) parameters.get(model.getTableHandler().prefixWithTableId() + parameter);
    }

    public Map getParameters() {
        if (saveFilterSort()) {
            HttpServletRequest request = (HttpServletRequest) model.getPageContext().getRequest();
            Map params = (Map) request.getSession().getAttribute(model.getTableHandler().prefixWithTableId());
            if (params != null) {
                return params;
            }
        }

        return this.parameters;
    }

    /**
     * Get a map of specific parameters
     */
    public Map getParameters(String parameter) {
        Map subset = new HashMap();

        String find = model.getTableHandler().prefixWithTableId() + parameter;

        Set set = parameters.keySet();
        for (Iterator iter = set.iterator(); iter.hasNext();) {
            String key = (String) iter.next();
            if (key.startsWith(find)) {
                String value = (String) parameters.get(key);
                subset.put(key, value);
            }
        }

        return subset;
    }

    /**
     * Get a map of specific parameters
     */
    public Map clearParameters(String parameter) {
        if (saveFilterSort()) {
            removeParametersInSession();
        }

        Map subset = new HashMap();

        Set set = parameters.keySet();

        for (Iterator iter = set.iterator(); iter.hasNext();) {
            String name = (String) iter.next();

            if (name.startsWith(model.getTableHandler().prefixWithTableId() + parameter)) {
                iter.remove();
            }
        }

        return subset;
    }

    /**
     * Take the parameters and format into hidden fields
     */
    public String getHiddenFields(String parameter) {
        StringBuffer sb = new StringBuffer();

        Set keys = parameters.keySet();

        for (Iterator iter = keys.iterator(); iter.hasNext();) {
            String name = (String) iter.next();

            if (((parameter == null) && !name.startsWith(model.getTableHandler().prefixWithTableId()))
                    || (name.startsWith(model.getTableHandler().prefixWithTableId() + parameter))) {
                String value = (String) parameters.get(name);
                sb.append("\n\t<input type=\"hidden\" name=\"").append(name).append("\" value=\"").append(value)
                        .append("\">\n");
            }
        }

        return sb.toString();
    }

    /**
     * Get a URI formated parameter string. Will look like &key=value
     */
    public String getParameterString(String parameter) {
        StringBuffer sb = new StringBuffer();

        Set keys = parameters.keySet();

        for (Iterator iter = keys.iterator(); iter.hasNext();) {
            String name = (String) iter.next();

            if (((parameter == null) && !name.startsWith(model.getTableHandler().prefixWithTableId()))
                    || (name.startsWith(model.getTableHandler().prefixWithTableId() + parameter))) {
                String value = (String) parameters.get(name);
                value = URLEncoder.encode(value);
                sb.append("&" + name + "=" + value);
            }
        }

        return sb.toString();
    }

    /**
     * Get parameter datum.
     */
    public String getURLParameterString(boolean filter, boolean sort, boolean page, boolean rowsDisplayed) {
        StringBuffer sb = new StringBuffer();

        if (filter) {
            sb.append(getParameterString(TableConstants.FILTER));
        }

        if (sort) {
            sb.append(getParameterString(TableConstants.SORT));
        }

        if (page) {
            sb.append(getParameterString(TableConstants.PAGE));
        }

        if (rowsDisplayed) {
            sb.append(getParameterString(TableConstants.CURRENT_ROWS_DISPLAYED));
        }

        sb.append(getParameterString(null));

        return sb.toString();
    }

    /**
     * Get all the action as hidden fields.
     */
    public String getFormHiddenFields(boolean filter, boolean sort, boolean page, boolean rowsDisplayed) {
        StringBuffer sb = new StringBuffer();

        if (filter) {
            sb.append(getHiddenFields(TableConstants.FILTER));
        }

        if (sort) {
            sb.append(getHiddenFields(TableConstants.SORT));
        }

        if (page) {
            sb.append(getHiddenFields(TableConstants.PAGE));
        }

        if (rowsDisplayed) {
            sb.append(getHiddenFields(TableConstants.CURRENT_ROWS_DISPLAYED));
        }

        sb.append(getHiddenFields(null));

        return sb.toString();
    }

    public void destroy() {
        if (!saveFilterSort()) {
            parameters.clear();
            parameters = null;
        }
    }

    private boolean saveFilterSort() {
        if (StringUtils.isNotEmpty(model.getTableHandler().getTable().getSaveFilterSort())
                && model.getTableHandler().getTable().getSaveFilterSort().equalsIgnoreCase("true")) {
            return true;
        }
        return false;
    }

    private void saveParametersInSession() {
        HttpServletRequest req = (HttpServletRequest) model.getPageContext().getRequest();
        req.getSession().setAttribute(model.getTableHandler().prefixWithTableId(), parameters);
    }

    private void removeParametersInSession() {
        HttpServletRequest req = (HttpServletRequest) model.getPageContext().getRequest();
        req.getSession().setAttribute(model.getTableHandler().prefixWithTableId(), new HashMap());
    }

    private boolean shouldUseSessionFilterSort() {
        boolean result = false;
        // user defined param set up in properties file
        String useSessionFilterSortFlagName = model.getProperties()
                .getProperty(TableProperties.USE_SESSION_FILTER_SORT);
        if (StringUtils.isNotBlank(useSessionFilterSortFlagName)) {
            String useSessionFilterSort = model.getPageContext().getRequest()
                    .getParameter(useSessionFilterSortFlagName);
            if (StringUtils.isNotEmpty(useSessionFilterSort) && useSessionFilterSort.equalsIgnoreCase("true")) {
                result = true;
            }
        }
        return result;
    }
}