| // *************************************************************************************************************************** |
| // * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * |
| // * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * |
| // * to you 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.apache.juneau.internal; |
| |
| import java.io.*; |
| import java.nio.charset.*; |
| |
| /** |
| * Utility class for creating {@link FileReader} objects. |
| */ |
| public final class FileReaderBuilder { |
| |
| private File file; |
| private Charset cs = Charset.defaultCharset(); |
| private boolean allowNoFile; |
| |
| /** |
| * Creates a new builder. |
| * |
| * @return A new builder. |
| */ |
| public static FileReaderBuilder create() { |
| return new FileReaderBuilder(); |
| } |
| |
| /** |
| * Creates a new builder initialized with the specified file. |
| * |
| * @param file The file being written to. |
| * @return A new builder. |
| */ |
| public static FileReaderBuilder create(File file) { |
| return new FileReaderBuilder().file(file); |
| } |
| |
| /** |
| * Sets the file being written from. |
| * |
| * @param file The file being written from. |
| * @return This object (for method chaining). |
| */ |
| public FileReaderBuilder file(File file) { |
| this.file = file; |
| return this; |
| } |
| |
| /** |
| * Sets the path of the file being written from. |
| * |
| * @param path The path of the file being written from. |
| * @return This object (for method chaining). |
| */ |
| public FileReaderBuilder file(String path) { |
| this.file = new File(path); |
| return this; |
| } |
| |
| /** |
| * Sets the character encoding of the file. |
| * |
| * @param cs |
| * The character encoding. |
| * The default is {@link Charset#defaultCharset()}. |
| * @return This object (for method chaining). |
| */ |
| public FileReaderBuilder charset(Charset cs) { |
| this.cs = cs; |
| return this; |
| } |
| |
| /** |
| * Sets the character encoding of the file. |
| * |
| * @param cs |
| * The character encoding. |
| * The default is {@link Charset#defaultCharset()}. |
| * @return This object (for method chaining). |
| */ |
| public FileReaderBuilder charset(String cs) { |
| this.cs = Charset.forName(cs); |
| return this; |
| } |
| |
| /** |
| * If called and the file is <jk>null</jk> or non-existent, then the {@link #build()} command will return an empty |
| * reader instead of a {@link FileNotFoundException}. |
| * |
| * @return This object (for method chaining). |
| */ |
| public FileReaderBuilder allowNoFile() { |
| this.allowNoFile = true; |
| return this; |
| } |
| |
| /** |
| * Creates a new File reader. |
| * |
| * @return A new File reader. |
| * @throws FileNotFoundException If file could not be found. |
| */ |
| public Reader build() throws FileNotFoundException { |
| if (allowNoFile && (file == null || ! file.exists())) |
| return new StringReader(""); |
| return new InputStreamReader(new FileInputStream(file), cs); |
| } |
| } |