Merge pull request #49 from prydin/prydin-partial-load

Added support for partial chunk/region load

.gitignore

@@ -77,10 +77,13 @@ local.properties
 # IDEA folder
 .idea/
 
+# .iml files
+*.iml
+
 # ignore javadoc for now
 doc/
 
 # ignore out
 out/
 
-*.patch
+*.patch

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Wed Mar 29 16:28:10 CEST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-all.zip

gradlew

@@ -1,5 +1,21 @@
 #!/usr/bin/env sh
 
+#
+# Copyright 2015 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.
+#
+
 ##############################################################################
 ##
 ##  Gradle start up script for UN*X
@@ -28,16 +44,16 @@ APP_NAME="Gradle"
 APP_BASE_NAME=`basename "$0"`
 
 # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS=""
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD="maximum"
 
-warn ( ) {
+warn () {
     echo "$*"
 }
 
-die ( ) {
+die () {
     echo
     echo "$*"
     echo
@@ -66,6 +82,7 @@ esac
 
 CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
 
+
 # Determine the Java command to use to start the JVM.
 if [ -n "$JAVA_HOME" ] ; then
     if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
@@ -109,10 +126,11 @@ if $darwin; then
     GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
 fi
 
-# For Cygwin, switch paths to Windows format before running java
-if $cygwin ; then
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
     APP_HOME=`cygpath --path --mixed "$APP_HOME"`
     CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+
     JAVACMD=`cygpath --unix "$JAVACMD"`
 
     # We build the pattern for arguments to be converted via cygpath
@@ -138,35 +156,30 @@ if $cygwin ; then
         else
             eval `echo args$i`="\"$arg\""
         fi
-        i=$((i+1))
+        i=`expr $i + 1`
     done
     case $i in
-        (0) set -- ;;
-        (1) set -- "$args0" ;;
-        (2) set -- "$args0" "$args1" ;;
-        (3) set -- "$args0" "$args1" "$args2" ;;
-        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
-        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
-        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
-        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
-        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
-        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
     esac
 fi
 
 # Escape application args
-save ( ) {
+save () {
     for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
     echo " "
 }
-APP_ARGS=$(save "$@")
+APP_ARGS=`save "$@"`
 
 # Collect all arguments for the java command, following the shell quoting and substitution rules
 eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
 
-# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
-if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
-  cd "$(dirname "$0")"
-fi
-
 exec "$JAVACMD" "$@"

gradlew.bat

@@ -1,3 +1,19 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
 @if "%DEBUG%" == "" @echo off
 @rem ##########################################################################
 @rem
@@ -13,8 +29,11 @@ if "%DIRNAME%" == "" set DIRNAME=.
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
 @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-set DEFAULT_JVM_OPTS=
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
 
 @rem Find java.exe
 if defined JAVA_HOME goto findJavaFromJavaHome
@@ -65,6 +84,7 @@ set CMD_LINE_ARGS=%*
 
 set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
+
 @rem Execute Gradle
 "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
 

src/main/java/net/querz/mca/Chunk.java

@@ -12,11 +12,14 @@
 import java.io.IOException;
 import java.io.RandomAccessFile;
 import java.util.Arrays;
+import static net.querz.mca.LoadFlags.*;
 
 public class Chunk {
 
 	public static final int DEFAULT_DATA_VERSION = 1628;
 
+	private boolean partial;
+
 	private int lastMCAUpdate;
 
 	private CompoundTag data;
@@ -49,47 +52,78 @@ public class Chunk {
 	 */
 	public Chunk(CompoundTag data) {
 		this.data = data;
-		initReferences();
+		initReferences(ALL_DATA);
 	}
 
-	private void initReferences() {
+	private void initReferences(long loadFlags) {
 		if (data == null) {
 			throw new NullPointerException("data cannot be null");
 		}
 		CompoundTag level;
 		if ((level = data.getCompoundTag("Level")) == null) {
 			throw new IllegalArgumentException("data does not contain \"Level\" tag");
 		}
-		this.dataVersion = data.getInt("DataVersion");
-		this.inhabitedTime = level.getLong("InhabitedTime");
-		this.lastUpdate = level.getLong("LastUpdate");
-		this.biomes = level.getIntArray("Biomes");
-		this.heightMaps = level.getCompoundTag("Heightmaps");
-		this.carvingMasks = level.getCompoundTag("CarvingMasks");
-		this.entities = level.containsKey("Entities") ? level.getListTag("Entities").asCompoundTagList() : null;
-		this.tileEntities = level.containsKey("TileEntities") ? level.getListTag("TileEntities").asCompoundTagList() : null;
-		this.tileTicks = level.containsKey("TileTicks") ? level.getListTag("TileTicks").asCompoundTagList() : null;
-		this.liquidTicks = level.containsKey("LiquidTicks") ? level.getListTag("LiquidTicks").asCompoundTagList() : null;
-		this.lights = level.containsKey("Lights") ? level.getListTag("Lights").asListTagList() : null;
-		this.liquidsToBeTicked = level.containsKey("LiquidsToBeTicked") ? level.getListTag("LiquidsToBeTicked").asListTagList() : null;
-		this.toBeTicked = level.containsKey("ToBeTicked") ? level.getListTag("ToBeTicked").asListTagList() : null;
-		this.postProcessing = level.containsKey("PostProcessing") ? level.getListTag("PostProcessing").asListTagList() : null;
-		this.status = level.getString("Status");
-		this.structures = level.getCompoundTag("Structures");
-		if (level.containsKey("Sections")) {
+		dataVersion = data.getInt("DataVersion");
+		inhabitedTime = level.getLong("InhabitedTime");
+		lastUpdate = level.getLong("LastUpdate");
+		if ((loadFlags & BIOMES) != 0) {
+			biomes = level.getIntArray("Biomes");
+		}
+		if ((loadFlags & HEIGHTMAPS) != 0) {
+			heightMaps = level.getCompoundTag("Heightmaps");
+		}
+		if ((loadFlags & CARVING_MASKS) != 0) {
+			carvingMasks = level.getCompoundTag("CarvingMasks");
+		}
+		if ((loadFlags & ENTITIES) != 0) {
+			entities = level.containsKey("Entities") ? level.getListTag("Entities").asCompoundTagList() : null;
+		}
+		if ((loadFlags & TILE_ENTITIES) != 0) {
+			tileEntities = level.containsKey("TileEntities") ? level.getListTag("TileEntities").asCompoundTagList() : null;
+		}
+		if ((loadFlags & TILE_TICKS) != 0) {
+			tileTicks = level.containsKey("TileTicks") ? level.getListTag("TileTicks").asCompoundTagList() : null;
+		}
+		if ((loadFlags & LIQUID_TICKS) != 0) {
+			liquidTicks = level.containsKey("LiquidTicks") ? level.getListTag("LiquidTicks").asCompoundTagList() : null;
+		}
+		if ((loadFlags & LIGHTS) != 0) {
+			lights = level.containsKey("Lights") ? level.getListTag("Lights").asListTagList() : null;
+		}
+		if ((loadFlags & LIQUIDS_TO_BE_TICKED) != 0) {
+			liquidsToBeTicked = level.containsKey("LiquidsToBeTicked") ? level.getListTag("LiquidsToBeTicked").asListTagList() : null;
+		}
+		if ((loadFlags & TO_BE_TICKED) != 0) {
+			toBeTicked = level.containsKey("ToBeTicked") ? level.getListTag("ToBeTicked").asListTagList() : null;
+		}
+		if ((loadFlags & POST_PROCESSING) != 0) {
+			postProcessing = level.containsKey("PostProcessing") ? level.getListTag("PostProcessing").asListTagList() : null;
+		}
+		status = level.getString("Status");
+		if ((loadFlags & STRUCTURES) != 0) {
+			structures = level.getCompoundTag("Structures");
+		}
+		if ((loadFlags & (BLOCK_LIGHTS|BLOCK_STATES|SKY_LIGHT)) != 0 && level.containsKey("Sections")) {
 			for (CompoundTag section : level.getListTag("Sections").asCompoundTagList()) {
 				int sectionIndex = section.getByte("Y");
 				if (sectionIndex > 15 || sectionIndex < 0) {
 					continue;
 				}
-				Section newSection = new Section(section, dataVersion);
+				Section newSection = new Section(section, dataVersion, loadFlags);
 				if (newSection.isEmpty()) {
 					continue;
 				}
-
-				this.sections[sectionIndex] = newSection;
+				sections[sectionIndex] = newSection;
 			}
 		}
+
+		// If we haven't requested the full set of data we can drop the underlying raw data to let the GC handle it.
+		if (loadFlags != ALL_DATA) {
+			data = null;
+			partial = true;
+		} else {
+			partial = false;
+		}
 	}
 
 	/**
@@ -98,9 +132,13 @@ private void initReferences() {
 	 * @param xPos The x-coordinate of the chunk.
 	 * @param zPos The z-coodrinate of the chunk.
 	 * @return The amount of bytes written to the RandomAccessFile.
+	 * @throws UnsupportedOperationException When something went wrong during writing.
 	 * @throws IOException When something went wrong during writing.
 	 */
 	public int serialize(RandomAccessFile raf, int xPos, int zPos) throws IOException {
+		if (partial) {
+			throw new UnsupportedOperationException("Partially loaded chunks cannot be serialized");
+		}
 		ByteArrayOutputStream baos = new ByteArrayOutputStream(4096);
 		try (BufferedOutputStream nbtOut = new BufferedOutputStream(CompressionType.ZLIB.compress(baos))) {
 			new NBTSerializer(false).toStream(new NamedTag(null, updateHandle(xPos, zPos)), nbtOut);
@@ -118,6 +156,16 @@ public int serialize(RandomAccessFile raf, int xPos, int zPos) throws IOExceptio
 	 * @throws IOException When something went wrong during reading.
 	 */
 	public void deserialize(RandomAccessFile raf) throws IOException {
+		deserialize(raf, ALL_DATA);
+	}
+
+	/**
+	 * Reads chunk data from a RandomAccessFile. The RandomAccessFile must already be at the correct position.
+	 * @param raf The RandomAccessFile to read the chunk data from.
+	 * @param loadFlags A logical or of {@link LoadFlags} constants indicating what data should be loaded
+	 * @throws IOException When something went wrong during reading.
+	 */
+	public void deserialize(RandomAccessFile raf, long loadFlags) throws IOException {
 		byte compressionTypeByte = raf.readByte();
 		CompressionType compressionType = CompressionType.getFromID(compressionTypeByte);
 		if (compressionType == null) {
@@ -127,7 +175,7 @@ public void deserialize(RandomAccessFile raf) throws IOException {
 		NamedTag tag = new NBTDeserializer(false).fromStream(dis);
 		if (tag != null && tag.getTag() instanceof CompoundTag) {
 			data = (CompoundTag) tag.getTag();
-			initReferences();
+			initReferences(loadFlags);
 		} else {
 			throw new IOException("invalid data tag: " + (tag == null ? "null" : tag.getClass().getName()));
 		}
@@ -571,7 +619,7 @@ public CompoundTag updateHandle(int xPos, int zPos) {
 		} else {
 			if (biomes != null && biomes.length == 1024) level.putIntArray("Biomes", biomes);
 		}
-		if (heightMaps != null) level.put("HeightMaps", heightMaps);
+		if (heightMaps != null) level.put("Heightmaps", heightMaps);
 		if (carvingMasks != null) level.put("CarvingMasks", carvingMasks);
 		if (entities != null) level.put("Entities", entities);
 		if (tileEntities != null) level.put("TileEntities", tileEntities);

src/main/java/net/querz/mca/LoadFlags.java

@@ -0,0 +1,24 @@
+package net.querz.mca;
+
+public class LoadFlags {
+
+	public static long BIOMES               = 0x0001;
+	public static long HEIGHTMAPS           = 0x0002;
+	public static long CARVING_MASKS        = 0x0004;
+	public static long ENTITIES             = 0x0008;
+	public static long TILE_ENTITIES        = 0x0010;
+	public static long TILE_TICKS           = 0x0040;
+	public static long LIQUID_TICKS         = 0x0080;
+	public static long TO_BE_TICKED         = 0x0100;
+	public static long POST_PROCESSING      = 0x0200;
+	public static long STRUCTURES           = 0x0400;
+	public static long BLOCK_LIGHTS         = 0x0800;
+	public static long BLOCK_STATES         = 0x1000;
+	public static long SKY_LIGHT            = 0x2000;
+	public static long LIGHTS               = 0x4000;
+	public static long LIQUIDS_TO_BE_TICKED = 0x8000;
+
+	public static long ALL_DATA             = 0xffffffffffffffffL;
+
+
+}

src/main/java/net/querz/mca/MCAFile.java

@@ -34,6 +34,17 @@ public MCAFile(int regionX, int regionZ) {
 	 * @throws IOException If something went wrong during deserialization.
 	 * */
 	public void deserialize(RandomAccessFile raf) throws IOException {
+		deserialize(raf, LoadFlags.ALL_DATA);
+	}
+
+	/**
+	 * Reads an .mca file from a {@code RandomAccessFile} into this object.
+	 * This method does not perform any cleanups on the data.
+	 * @param raf The {@code RandomAccessFile} to read from.
+	 * @param loadFlags A logical or of {@link LoadFlags} constants indicating what data should be loaded
+	 * @throws IOException If something went wrong during deserialization.
+	 * */
+	public void deserialize(RandomAccessFile raf, long loadFlags) throws IOException {
 		chunks = new Chunk[1024];
 		for (int i = 0; i < 1024; i++) {
 			raf.seek(i * 4);
@@ -47,7 +58,7 @@ public void deserialize(RandomAccessFile raf) throws IOException {
 			int timestamp = raf.readInt();
 			Chunk chunk = new Chunk(timestamp);
 			raf.seek(4096 * offset + 4); //+4: skip data size
-			chunk.deserialize(raf);
+			chunk.deserialize(raf, loadFlags);
 			chunks[i] = chunk;
 		}
 	}