| /* |
| * 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.commons.text.lookup; |
| |
| import java.nio.file.Files; |
| import java.nio.file.Paths; |
| |
| import org.apache.commons.lang3.StringUtils; |
| import org.apache.commons.text.StringSubstitutor; |
| |
| /** |
| * Looks up keys from a file. |
| * <p> |
| * Using a {@link StringLookup} from the {@link StringLookupFactory}: |
| * </p> |
| * |
| * <pre> |
| * StringLookupFactory.INSTANCE.fileStringLookup().lookup(UTF-8:com/domain/document.properties"); |
| * </pre> |
| * <p> |
| * Using a {@link StringSubstitutor}: |
| * </p> |
| * |
| * <pre> |
| * StringSubstitutor.createInterpolator().replace("... ${file:UTF-8:com/domain/document.properties} ...")); |
| * </pre> |
| * <p> |
| * The above examples convert {@code "UTF-8:SomePath"} to the contents of the file. |
| * </p> |
| * |
| * @since 1.5 |
| */ |
| final class FileStringLookup extends AbstractStringLookup { |
| |
| /** |
| * Defines the singleton for this class. |
| */ |
| static final AbstractStringLookup INSTANCE = new FileStringLookup(); |
| |
| /** |
| * No need to build instances for now. |
| */ |
| private FileStringLookup() { |
| // empty |
| } |
| |
| /** |
| * Looks up the value for the key in the format "charsetName:DocumentPath". |
| * <p> |
| * For example: "UTF-8:com/domain/document.properties". |
| * </p> |
| * |
| * @param key the key to be looked up, may be null |
| * @return The value associated with the key. |
| */ |
| @Override |
| public String lookup(final String key) { |
| if (key == null) { |
| return null; |
| } |
| final String[] keys = key.split(String.valueOf(SPLIT_CH)); |
| final int keyLen = keys.length; |
| if (keyLen < 2) { |
| throw IllegalArgumentExceptions |
| .format("Bad file key format [%s], expected format is CharsetName:DocumentPath.", key); |
| } |
| final String charsetName = keys[0]; |
| final String fileName = StringUtils.substringAfter(key, SPLIT_CH); |
| try { |
| return new String(Files.readAllBytes(Paths.get(fileName)), charsetName); |
| } catch (final Exception e) { |
| throw IllegalArgumentExceptions.format(e, "Error looking up file [%s] with charset [%s].", fileName, |
| charsetName); |
| } |
| } |
| |
| } |