jodd.csselly.selector.PseudoFunctionSelector Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of extractor Show documentation
Web Data Extractor - Extract data from common web format. like HTML,XML,JSON.
The newest version!
// Copyright (c) 2003-present, Jodd Team (http://jodd.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

package jodd.csselly.selector;

import jodd.csselly.CSSellyException;
import jodd.csselly.Selector;
import jodd.lagarto.dom.Node;
import jodd.lagarto.dom.NodeFilter;
import jodd.lagarto.dom.NodeListFilter;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Pseudo function selector.
 */
public class PseudoFunctionSelector extends Selector implements NodeFilter, NodeListFilter {

    protected static final Map PSEUDO_FUNCTION_MAP;

    static {
        PSEUDO_FUNCTION_MAP = new HashMap<>(8);

        registerPseudoFunction(PseudoFunction.NTH_CHILD.class);
        registerPseudoFunction(PseudoFunction.NTH_LAST_CHILD.class);
        registerPseudoFunction(PseudoFunction.NTH_LAST_OF_TYPE.class);
        registerPseudoFunction(PseudoFunction.NTH_OF_TYPE.class);

        registerPseudoFunction(PseudoFunction.EQ.class);
        registerPseudoFunction(PseudoFunction.GT.class);
        registerPseudoFunction(PseudoFunction.LT.class);
        registerPseudoFunction(PseudoFunction.CONTAINS.class);
    }

    /**
     * Registers pseudo function.
     */
    public static void registerPseudoFunction(Class pseudoFunctionType) {
        PseudoFunction pseudoFunction;
        try {
            pseudoFunction = pseudoFunctionType.newInstance();
        } catch (Exception ex) {
            throw new CSSellyException(ex);
        }
        PSEUDO_FUNCTION_MAP.put(pseudoFunction.getPseudoFunctionName(), pseudoFunction);
    }

    /**
     * Lookups pseudo function for given pseudo function name.
     */
    public static PseudoFunction lookupPseudoFunction(String pseudoFunctionName) {
        PseudoFunction pseudoFunction = PSEUDO_FUNCTION_MAP.get(pseudoFunctionName);
        if (pseudoFunction == null) {
            throw new CSSellyException("Unsupported pseudo function: " + pseudoFunctionName);
        }
        return pseudoFunction;
    }


    // ---------------------------------------------------------------- selector

    protected final PseudoFunction pseudoFunction;
    protected final String expression;
    protected final E parsedExpression;

    /**
     * Creates pseudo function selector for given function and expression.
     */
    @SuppressWarnings("unchecked")
    public PseudoFunctionSelector(String functionName, String expression) {
        super(Type.PSEUDO_FUNCTION);
        this.pseudoFunction = (PseudoFunction) lookupPseudoFunction(functionName.trim());
        this.expression = expression;
        this.parsedExpression = pseudoFunction.parseExpression(expression);
    }

    /**
     * Returns {@link PseudoFunction pseudo function}.
     */
    public PseudoFunction getPseudoFunction() {
        return pseudoFunction;
    }

    /**
     * Returns expression string.
     */
    public String getExpression() {
        return expression;
    }

    /**
     * Returns parsed expression object.
     */
    public E getParsedExpression() {
        return parsedExpression;
    }

    /**
     * Matches nodes with this pseudo function selector.
     */
    public boolean accept(Node node) {
        return pseudoFunction.match(node, parsedExpression);
    }

    /**
     * Accepts node within selected results. Invoked after results are matched.
     */
    public boolean accept(List currentResults, Node node, int index) {
        return pseudoFunction.match(currentResults, node, index, parsedExpression);
    }

}