Java tutorial
/* * Forge Mod Loader * Copyright (c) 2012-2013 cpw. * All rights reserved. This program and the accompanying materials * are made available under the terms of the GNU Lesser Public License v2.1 * which accompanies this distribution, and is available at * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html * * Contributors: * cpw - implementation */ package cpw.mods.fml.common; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.util.Map; import org.apache.logging.log4j.Level; import com.google.common.base.Throwables; import com.google.common.collect.Maps; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonParseException; import com.google.gson.JsonParser; import com.google.gson.TypeAdapter; import com.google.gson.stream.JsonReader; import com.google.gson.stream.JsonWriter; import cpw.mods.fml.common.versioning.ArtifactVersion; import cpw.mods.fml.common.versioning.VersionParser; public class MetadataCollection { @SuppressWarnings("unused") private String modListVersion; private ModMetadata[] modList; private Map<String, ModMetadata> metadatas = Maps.newHashMap(); public static MetadataCollection from(InputStream inputStream, String sourceName) { if (inputStream == null) { return new MetadataCollection(); } InputStreamReader reader = new InputStreamReader(inputStream); try { MetadataCollection collection; Gson gson = new GsonBuilder().registerTypeAdapter(ArtifactVersion.class, new ArtifactVersionAdapter()) .create(); JsonParser parser = new JsonParser(); JsonElement rootElement = parser.parse(reader); if (rootElement.isJsonArray()) { collection = new MetadataCollection(); JsonArray jsonList = rootElement.getAsJsonArray(); collection.modList = new ModMetadata[jsonList.size()]; int i = 0; for (JsonElement mod : jsonList) { collection.modList[i++] = gson.fromJson(mod, ModMetadata.class); } } else { collection = gson.fromJson(rootElement, MetadataCollection.class); } collection.parseModMetadataList(); return collection; } catch (JsonParseException e) { FMLLog.log(Level.ERROR, e, "The mcmod.info file in %s cannot be parsed as valid JSON. It will be ignored", sourceName); return new MetadataCollection(); } catch (Exception e) { throw Throwables.propagate(e); } } private void parseModMetadataList() { for (ModMetadata modMetadata : modList) { metadatas.put(modMetadata.modId, modMetadata); } } public ModMetadata getMetadataForId(String modId, Map<String, Object> extraData) { if (!metadatas.containsKey(modId)) { ModMetadata dummy = new ModMetadata(); dummy.modId = modId; dummy.name = (String) extraData.get("name"); dummy.version = (String) extraData.get("version"); dummy.autogenerated = true; metadatas.put(modId, dummy); } return metadatas.get(modId); } public static class ArtifactVersionAdapter extends TypeAdapter<ArtifactVersion> { @Override public void write(JsonWriter out, ArtifactVersion value) throws IOException { // no op - we never write these out } @Override public ArtifactVersion read(JsonReader in) throws IOException { return VersionParser.parseVersionReference(in.nextString()); } } }