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/* * Copyright 2012-2016 the original author or authors. * * 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 * * https://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.springframework.boot.configurationmetadata; import java.io.IOException; import java.io.InputStream; import java.nio.charset.Charset; import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.Set; import java.util.stream.Collectors; import org.springframework.ide.eclipse.org.json.JSONException; /** * Load a {@link ConfigurationMetadataRepository} from the content of arbitrary * resource(s). * * @author Stephane Nicoll * @since 1.3.0 */ public final class ConfigurationMetadataRepositoryJsonBuilder { /** * UTF-8 Charset. */ public static final Charset UTF_8 = Charset.forName("UTF-8"); private Charset defaultCharset = UTF_8; private final JsonReader reader = new JsonReader(); private final List<RawConfigurationMetadata> rawDatas = new ArrayList<>(); private ConfigurationMetadataRepositoryJsonBuilder(Charset defaultCharset) { this.defaultCharset = defaultCharset; } /** * Add the content of a {@link ConfigurationMetadataRepository} defined by the * specified {@link InputStream} json document using the default charset. If this * metadata repository holds items that were loaded previously, these are ignored. * <p> * Leaves the stream open when done. * @param inputStream the source input stream * @return this builder * @throws IOException in case of I/O errors */ public ConfigurationMetadataRepositoryJsonBuilder withJsonResource(InputStream inputStream) throws IOException { return withJsonResource(inputStream, this.defaultCharset); } /** * Add the content of a {@link ConfigurationMetadataRepository} defined by the * specified {@link InputStream} json document using the specified {@link Charset}. If * this metadata repository holds items that were loaded previously, these are * ignored. * <p> * Leaves the stream open when done. * @param inputStream the source input stream * @param charset the charset of the input * @return this builder * @throws IOException in case of I/O errors */ public ConfigurationMetadataRepositoryJsonBuilder withJsonResource(InputStream inputStream, Charset charset) throws IOException { if (inputStream == null) { throw new IllegalArgumentException("InputStream must not be null."); } this.rawDatas.add(parseRaw(inputStream, charset)); return this; } /** * Build a {@link ConfigurationMetadataRepository} with the current state of this * builder. * @return this builder */ public ConfigurationMetadataRepository build() { SimpleConfigurationMetadataRepository result = new SimpleConfigurationMetadataRepository(); result.include(create(rawDatas)); return result; } private RawConfigurationMetadata parseRaw(InputStream in, Charset charset) throws IOException { try { return this.reader.read(in, charset); } catch (IOException ex) { throw new IllegalArgumentException("Failed to read configuration " + "metadata", ex); } catch (JSONException ex) { throw new IllegalArgumentException("Invalid configuration " + "metadata document", ex); } } private SimpleConfigurationMetadataRepository create(Iterable<RawConfigurationMetadata> metadatas) { SimpleConfigurationMetadataRepository repository = new SimpleConfigurationMetadataRepository(); for (RawConfigurationMetadata metadata : metadatas) { repository.add(metadata.getSources()); } for (RawConfigurationMetadata metadata : metadatas) { for (ConfigurationMetadataItem item : metadata.getItems()) { ConfigurationMetadataSource source = getSource(metadata, item); repository.add(item, source); } } for (RawConfigurationMetadata metadata : metadatas) { Map<String, ConfigurationMetadataProperty> allProperties = repository.getAllProperties(); for (ConfigurationMetadataHint hint : metadata.getHints()) { ConfigurationMetadataProperty property = allProperties.get(hint.getId()); if (property != null) { addValueHints(property, hint); } else { String id = hint.resolveId(); property = allProperties.get(id); if (property != null) { if (hint.isMapKeyHints()) { addMapHints(property, hint); } else { addValueHints(property, hint); } } } } } return repository; } private void addValueHints(ConfigurationMetadataProperty property, ConfigurationMetadataHint hint) { addAll(property.getHints().getValueHints(), hint.getValueHints()); property.getHints().getValueProviders().addAll(hint.getValueProviders()); } private void addMapHints(ConfigurationMetadataProperty property, ConfigurationMetadataHint hint) { addAll(property.getHints().getKeyHints(), hint.getValueHints()); property.getHints().getKeyProviders().addAll(hint.getValueProviders()); } /** * Add a bunch of hints to a list, but guard against duplicates. */ private void addAll(List<ValueHint> existing, List<ValueHint> toAdd) { if (existing.isEmpty()) { existing.addAll(toAdd); } else if (toAdd.isEmpty()) { //nothing to add } else { Set<Object> existingValues = existing.stream().map((hint) -> "" + hint.getValue()) .collect(Collectors.toSet()); for (ValueHint hint : toAdd) { if (!existingValues.contains("" + hint.getValue())) { existing.add(hint); } } } } private ConfigurationMetadataSource getSource(RawConfigurationMetadata metadata, ConfigurationMetadataItem item) { if (item.getSourceType() != null) { return metadata.getSource(item.getSourceType()); } return null; } /** * Create a new builder instance using {@link #UTF_8} as the default charset and the * specified json resource. * @param inputStreams the source input streams * @return a new {@link ConfigurationMetadataRepositoryJsonBuilder} instance. * @throws IOException on error */ public static ConfigurationMetadataRepositoryJsonBuilder create(InputStream... inputStreams) throws IOException { ConfigurationMetadataRepositoryJsonBuilder builder = create(); for (InputStream inputStream : inputStreams) { builder = builder.withJsonResource(inputStream); } return builder; } /** * Create a new builder instance using {@link #UTF_8} as the default charset. * @return a new {@link ConfigurationMetadataRepositoryJsonBuilder} instance. */ public static ConfigurationMetadataRepositoryJsonBuilder create() { return create(UTF_8); } /** * Create a new builder instance using the specified default {@link Charset}. * @param defaultCharset the default charset to use * @return a new {@link ConfigurationMetadataRepositoryJsonBuilder} instance. */ public static ConfigurationMetadataRepositoryJsonBuilder create(Charset defaultCharset) { return new ConfigurationMetadataRepositoryJsonBuilder(defaultCharset); } }