ru.histone.evaluator.functions.node.string.Strip Maven / Gradle / Ivy

Go to download
/**
 *    Copyright 2013 MegaFon
 *
 *    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 ru.histone.evaluator.functions.node.string;

import ru.histone.evaluator.functions.node.NodeFunction;
import ru.histone.evaluator.nodes.Node;
import ru.histone.evaluator.nodes.NodeFactory;
import ru.histone.evaluator.nodes.StringHistoneNode;

/**
 * Removes all specified symbols from target string

 */
public class Strip extends NodeFunction {

    public Strip(NodeFactory nodeFactory) {
        super(nodeFactory);
    }

    @Override
    public String getName() {
        return "strip";
    }

    @Override
    public Node execute(StringHistoneNode target, Node... args) {
        String value = target.getValue();
        if (args.length > 0) {
            StringBuilder separator = new StringBuilder();
            for (Node argNode : args) {
                if (argNode.isString()) {
                    separator.append(argNode.getAsString().getValue());
                }
            }
            return getNodeFactory().string(strip(value, separator.toString()));
        } else {
            return getNodeFactory().string(strip(value, " \r\n\t"));
        }

    }

    private String strip(String str, String stripChars) {
        final int strLen = str.length();

        if (stripChars.isEmpty()) {
            return str;
        }

        int start = 0;
        while ((start != strLen) && (stripChars.indexOf(str.charAt(start)) != -1)) {
            start++;
        }

        int end = str.length();
        while ((end != 0) && (stripChars.indexOf(str.charAt(end - 1)) != -1)) {
            end--;
        }

        if (start >= end) {
            return "";
        } else {
            return str.substring(start, end);
        }
    }

}