com.r573.enfili.common.io.file.PathBuilder.java Source code

Introduction

Here is the source code for com.r573.enfili.common.io.file.PathBuilder.java

Source

/*
 * Enfili
 * Project hosted at https://github.com/ryanhosp/enfili/
 * Copyright 2013 Ho Siaw Ping Ryan
 *    
 * 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.r573.enfili.common.io.file;

import java.io.File;
import java.util.LinkedList;

import org.apache.commons.io.FilenameUtils;

public class PathBuilder {
    private LinkedList<String> elements;
    private String separator;
    private String prefix;

    public PathBuilder(String initialPath) {
        init(initialPath);
    }

    public PathBuilder(File file) {
        init(file.getPath());
    }

    private void init(String initialPath) {
        this.separator = File.separator;
        this.prefix = FilenameUtils.getPrefix(initialPath);

        this.elements = new LinkedList<String>();

        String pathWithoutPrefix = FilenameUtils.getPath(initialPath);
        String[] initialPathParts = pathWithoutPrefix.split("\\" + separator);
        for (int i = 0; i < initialPathParts.length; i++) {
            String thisPart = initialPathParts[i];
            if ((thisPart != null) && (!thisPart.isEmpty())) {
                elements.add(thisPart);
            }
        }
        elements.add(FilenameUtils.getName(initialPath));
    }

    private String cleanElement(String element) {
        if (element.startsWith(separator)) {
            element = element.substring(1);
        }
        if (element.endsWith(separator)) {
            element = element.substring(0, element.length() - 1);
        }
        return element;
    }

    public PathBuilder append(String element) {
        if (element == null) {
            return this;
        }
        element = cleanElement(element);
        elements.addLast(element);
        return this;
    }

    public PathBuilder prepend(String element) {
        if (element == null) {
            return this;
        }
        element = cleanElement(element);
        elements.addFirst(element);
        return this;
    }

    public PathBuilder removeFront(int numElements) {
        for (int i = 0; i < numElements; i++) {
            elements.removeFirst();
        }
        return this;
    }

    public PathBuilder removeBack(int numElements) {
        for (int i = 0; i < numElements; i++) {
            elements.removeLast();
        }
        return this;
    }

    public PathBuilder removeFront() {
        return removeFront(1);
    }

    public PathBuilder removeBack() {
        return removeBack(1);
    }

    public PathBuilder removeAllFromFrontExcept(int numElementsToRetain) {
        int numElements = elements.size();
        for (int i = numElements; i > numElementsToRetain; i--) {
            elements.removeFirst();
        }
        return this;
    }

    public PathBuilder removeAllFromBackExcept(int numElementsToRetain) {
        int numElements = elements.size();
        for (int i = numElementsToRetain; i < numElements; i++) {
            elements.removeLast();
        }
        return this;
    }

    public String toPath() {
        String path = prefix;
        for (String element : elements) {
            path = FilenameUtils.concat(path, element);
        }
        return path;
    }

    public File toFile() {
        return new File(toPath());
    }
}