001/* 002 * Trident - A Multithreaded Server Alternative 003 * Copyright 2014 The TridentSDK Team 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018package net.tridentsdk.meta.nbt; 019 020import com.google.common.base.Charsets; 021import net.tridentsdk.util.TridentLogger; 022 023import java.io.DataOutput; 024import java.io.IOException; 025import java.util.List; 026 027/** 028 * @author The TridentSDK Team 029 * @since 0.3-alpha-DP 030 */ 031public class NBTEncoder { 032 final DataOutput output; 033 034 public NBTEncoder(DataOutput output) { 035 this.output = output; 036 } 037 038 public void encode(CompoundTag tag) throws NBTException { 039 try { 040 this.writeTag(tag); 041 } catch (IOException e) { 042 TridentLogger.get().error(new NBTException("IO Error encoding the NBT Data", e)); 043 } 044 } 045 046 private void writeCompoundTag(CompoundTag tag) throws IOException { 047 for (NBTTag inner : tag.listTags()) { 048 this.writeTag(inner); 049 } 050 //Write Tag_End to signify end of Compound 051 this.output.writeByte(TagType.END.id()); 052 } 053 054 private void writeListTag(ListTag tag) throws IOException { 055 //Write inner tag-type id 056 this.output.writeByte(tag.getInnerType().id()); 057 058 List<NBTTag> innerTags = tag.listTags(); 059 this.output.writeInt(innerTags.size()); 060 061 for (NBTTag inner : innerTags) { 062 this.writeTag(inner, false, false); 063 } 064 } 065 066 public void writeTag(NBTTag tag) throws IOException { 067 writeTag(tag, true, true); 068 } 069 070 private void writeTag(NBTTag tag, boolean name, boolean id) throws IOException { 071 if (id) { 072 this.output.writeByte(tag.type().id()); 073 } 074 075 if (tag.hasName() && name) { 076 this.writeString(tag.name()); 077 } 078 079 switch (tag.type()) { 080 case BYTE: 081 this.output.writeByte((int) tag.asType(ByteTag.class).value()); 082 break; 083 084 case SHORT: 085 this.output.writeShort((int) tag.asType(ShortTag.class).value()); 086 break; 087 088 case INT: 089 this.output.writeInt(tag.asType(IntTag.class).value()); 090 break; 091 092 case LONG: 093 this.output.writeLong(tag.asType(LongTag.class).value()); 094 break; 095 096 case FLOAT: 097 this.output.writeFloat(tag.asType(FloatTag.class).value()); 098 break; 099 case DOUBLE: 100 this.output.writeDouble(tag.asType(DoubleTag.class).value()); 101 break; 102 103 case BYTE_ARRAY: 104 byte[] barray = tag.asType(ByteArrayTag.class).value(); 105 this.output.writeInt(barray.length); 106 this.output.write(barray); 107 break; 108 109 case STRING: 110 this.writeString(tag.asType(StringTag.class).value()); 111 break; 112 113 case LIST: 114 this.writeListTag(tag.asType(ListTag.class)); 115 break; 116 117 case COMPOUND: 118 this.writeCompoundTag(tag.asType(CompoundTag.class)); 119 break; 120 121 case INT_ARRAY: 122 int[] iarray = tag.asType(IntArrayTag.class).value(); 123 this.output.writeInt(iarray.length); 124 for (int anIarray : iarray) { 125 this.output.writeInt(anIarray); 126 } 127 break; 128 129 default: 130 //Shouldn't/Can't happen 131 break; 132 } 133 } 134 135 private void writeString(String s) throws IOException { 136 this.output.writeShort(s.length()); 137 this.output.write(s.getBytes(Charsets.UTF_8)); 138 } 139}