com.adaptris.core.services.metadata.xpath.XpathQueryHelper.java Source code

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Here is the source code for com.adaptris.core.services.metadata.xpath.XpathQueryHelper.java

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/*
 * Copyright 2015 Adaptris Ltd.
 * 
 * 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 com.adaptris.core.services.metadata.xpath;

import org.apache.commons.lang.StringUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import com.adaptris.core.CoreException;
import com.adaptris.core.util.ExceptionHelper;
import com.adaptris.util.text.xml.XPath;

final class XpathQueryHelper {

    static String resolveSingleTextItem(Document doc, XPath xp, String expr, boolean allowEmptyResults)
            throws CoreException {
        String queryResult = null;
        try {
            String node = xp.selectSingleTextItem(doc, expr);
            if (StringUtils.isEmpty(node) && !allowEmptyResults) {
                throw new CoreException(expr + " returned no data");
            }
            queryResult = node;
        } catch (Exception e) {
            throw ExceptionHelper.wrapCoreException(e);
        }
        return queryResult;
    }

    static String resolveMultipleTextItems(Document doc, XPath xp, String expr, boolean allowEmptyResults,
            String sep) throws CoreException {
        String queryResult = null;
        try {
            String[] nodes = xp.selectMultipleTextItems(doc, expr);
            if (isEmpty(nodes) && !allowEmptyResults) {
                throw new CoreException(expr + " returned [" + nodes.length + "] nodes");
            }
            StringBuilder result = new StringBuilder();
            for (int i = 0; i < nodes.length; i++) {
                result.append(StringUtils.defaultIfBlank(nodes[i], ""));
                if (i < nodes.length - 1) {
                    result.append(sep);
                }
            }
            queryResult = result.toString();
        } catch (Exception e) {
            throw ExceptionHelper.wrapCoreException(e);
        }
        return queryResult;
    }

    static Node resolveSingleNode(Document doc, XPath xp, String expr, boolean allowNull) throws CoreException {
        Node queryResult = null;
        try {
            queryResult = xp.selectSingleNode(doc, expr);
            if (queryResult == null && !allowNull) {
                throw new CoreException("Query [" + expr + "] return null");
            }
        } catch (Exception e) {
            throw ExceptionHelper.wrapCoreException(e);
        }
        return queryResult;
    }

    static NodeList resolveNodeList(Document doc, XPath xp, String expr, boolean allowNull) throws CoreException {
        NodeList queryResult = null;
        try {
            queryResult = xp.selectNodeList(doc, expr);
            if (queryResult == null && !allowNull) {
                throw new CoreException("Query [" + expr + "] returned null");
            }
        } catch (Exception e) {
            throw ExceptionHelper.wrapCoreException(e);
        }
        return queryResult;
    }

    private static final boolean isEmpty(String[] list) {
        return list.length == 0;
    }

}