Encoding converter (in progress)

jni/NativeFormats/util/AndroidUtil.cpp

@@ -29,6 +29,7 @@ const char * const AndroidUtil::Class_java_io_PrintStream = "java/io/PrintStream
 const char * const AndroidUtil::Class_ZLibrary = "org/geometerplus/zlibrary/core/library/ZLibrary";
 const char * const AndroidUtil::Class_NativeFormatPlugin = "org/geometerplus/fbreader/formats/NativeFormatPlugin";
 const char * const AndroidUtil::Class_PluginCollection = "org/geometerplus/fbreader/formats/PluginCollection";
+const char * const AndroidUtil::Class_JavaEncodingCollection = "org/geometerplus/fbreader/formats/JavaEncodingCollection";
 const char * const AndroidUtil::Class_Paths = "org/geometerplus/fbreader/Paths";
 const char * const AndroidUtil::Class_ZLFile = "org/geometerplus/zlibrary/core/filesystem/ZLFile";
 const char * const AndroidUtil::Class_Book = "org/geometerplus/fbreader/library/Book";
@@ -57,6 +58,11 @@ jmethodID AndroidUtil::MID_NativeFormatPlugin_supportedFileType;
 
 jmethodID AndroidUtil::SMID_PluginCollection_Instance;
 
+jmethodID AndroidUtil::SMID_JavaEncodingCollection_Instance;
+jmethodID AndroidUtil::MID_JavaEncodingCollection_getEncoding_int;
+jmethodID AndroidUtil::MID_JavaEncodingCollection_getEncoding_String;
+jmethodID AndroidUtil::MID_JavaEncodingCollection_isEncodingSupported;
+
 jmethodID AndroidUtil::SMID_ZLFile_createFileByPath;
 jmethodID AndroidUtil::MID_ZLFile_children;
 jmethodID AndroidUtil::MID_ZLFile_exists;
@@ -142,6 +148,13 @@ bool AndroidUtil::init(JavaVM* jvm) {
 	CHECK_NULL( SMID_PluginCollection_Instance = env->GetStaticMethodID(cls, "Instance", "()Lorg/geometerplus/fbreader/formats/PluginCollection;") );
 	env->DeleteLocalRef(cls);
 
+	CHECK_NULL( cls = env->FindClass(Class_JavaEncodingCollection) );
+	CHECK_NULL( SMID_JavaEncodingCollection_Instance = env->GetStaticMethodID(cls, "Instance", "()Lorg/geometerplus/fbreader/formats/JavaEncodingCollection;") );
+	CHECK_NULL( MID_JavaEncodingCollection_getEncoding_String = env->GetMethodID(cls, "getEncoding", "(Ljava/lang/String;)Lorg/geometerplus/fbreader/formats/Encoding;") );
+	CHECK_NULL( MID_JavaEncodingCollection_getEncoding_int = env->GetMethodID(cls, "getEncoding", "(I)Lorg/geometerplus/fbreader/formats/Encoding;") );
+	CHECK_NULL( MID_JavaEncodingCollection_isEncodingSupported = env->GetMethodID(cls, "isEncodingSupported", "()Z") );
+	env->DeleteLocalRef(cls);
+
 	CHECK_NULL( cls = env->FindClass(Class_ZLFile) );
 	CHECK_NULL( SMID_ZLFile_createFileByPath = env->GetStaticMethodID(cls, "createFileByPath", "(Ljava/lang/String;)Lorg/geometerplus/zlibrary/core/filesystem/ZLFile;") );
 	CHECK_NULL( MID_ZLFile_children = env->GetMethodID(cls, "children", "()Ljava/util/List;") );

jni/NativeFormats/util/AndroidUtil.h

@@ -40,6 +40,7 @@ public:
 	static const char * const Class_ZLFile;
 	static const char * const Class_NativeFormatPlugin;
 	static const char * const Class_PluginCollection;
+	static const char * const Class_JavaEncodingCollection;
 	static const char * const Class_Paths;
 	static const char * const Class_Book;
 	static const char * const Class_Tag;
@@ -75,6 +76,11 @@ public:
 
 	static jmethodID SMID_PluginCollection_Instance;
 
+	static jmethodID SMID_JavaEncodingCollection_Instance;
+	static jmethodID MID_JavaEncodingCollection_getEncoding_String;
+	static jmethodID MID_JavaEncodingCollection_getEncoding_int;
+	static jmethodID MID_JavaEncodingCollection_isEncodingSupported;
+
 	static jmethodID SMID_Paths_cacheDirectory;
 
 	static jfieldID FID_Book_File;

jni/NativeFormats/zlibrary/core/src/encoding/JavaEncodingConverter.cpp

@@ -17,6 +17,7 @@
  * 02110-1301, USA.
  */
 
+#include <AndroidUtil.h>
 #include <ZLUnicodeUtil.h>
 
 #include "JavaEncodingConverter.h"
@@ -32,12 +33,20 @@ public:
 	void reset();
 	bool fillTable(int *map);
 
+private:
+	jobject myJavaConverter;
+
 friend class JavaEncodingConverterProvider;
 };
 
 bool JavaEncodingConverterProvider::providesConverter(const std::string &encoding) {
-	// TODO: implement
-	return false;
+	JNIEnv *env = AndroidUtil::getEnv();
+	jclass cls = env->FindClass(AndroidUtil::Class_JavaEncodingCollection);
+	jobject collection = env->CallStaticObjectMethod(cls, AndroidUtil::SMID_JavaEncodingCollection_Instance);
+	jboolean result = env->CallBooleanMethod(collection, AndroidUtil::MID_JavaEncodingCollection_isEncodingSupported);
+	env->DeleteLocalRef(collection);
+	env->DeleteLocalRef(cls);
+	return result != 0;
 }
 
 shared_ptr<ZLEncodingConverter> JavaEncodingConverterProvider::createConverter(const std::string &encoding) {

proguard.cfg

@@ -35,6 +35,14 @@
 -keepclassmembers class org.geometerplus.fbreader.formats.FormatPlugin {
     public ** supportedFileType();
 }
+-keep class org.geometerplus.fbreader.formats.Encoding
+-keep class org.geometerplus.fbreader.formats.JavaEncodingCollection
+-keepclassmembers class org.geometerplus.fbreader.formats.JavaEncodingCollection {
+    public static ** Instance();
+    public ** getEncoding(java.lang.String);
+    public ** getEncoding(int);
+		public boolean isEncodingSupported(java.lang.String);
+}
 -keep class org.geometerplus.fbreader.Paths
 -keepclassmembers class org.geometerplus.fbreader.Paths {
     public static ** cacheDirectory();

src/org/geometerplus/fbreader/formats/EncodingConverter.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2007-2012 Geometer Plus <contact@geometerplus.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+package org.geometerplus.fbreader.formats;
+
+import java.nio.*;
+import java.nio.charset.*;
+
+public class EncodingConverter {
+	private CharsetDecoder myDecoder;
+	private CharsetEncoder myEncoder;
+
+	EncodingConverter(String encoding) {
+		myDecoder = Charset.forName(encoding).newDecoder()
+			.onMalformedInput(CodingErrorAction.REPLACE)
+			.onUnmappableCharacter(CodingErrorAction.REPLACE);
+		myEncoder = Charset.forName("utf-8").newEncoder();
+	}
+
+	// we assume out is large enough for this conversion
+	// returns number of filled bytes in out buffer
+	int convert(byte[] in, int inOffset, int inLength, byte[] out, int outOffset) {
+		final ByteBuffer inBuffer = ByteBuffer.wrap(in, inOffset, inLength);
+		final ByteBuffer outBuffer = ByteBuffer.wrap(out, outOffset, out.length - outOffset);
+		try {
+			final CharBuffer charBuffer = myDecoder.decode(inBuffer);
+			myEncoder.encode(charBuffer, outBuffer, true);
+			return charBuffer.length();
+		} catch (CharacterCodingException e) {
+			return 0;
+		}
+	}
+
+	void reset() {
+		myDecoder.reset();
+		myEncoder.reset();
+	}
+}

src/org/geometerplus/fbreader/formats/FilteredEncodingCollection.java

@@ -35,7 +35,7 @@ abstract class FilteredEncodingCollection extends EncodingCollection {
 		);
 	}
 	
-	protected abstract boolean isEncodingSupported(String name);
+	public abstract boolean isEncodingSupported(String name);
 
 	@Override
 	public List<Encoding> encodings() {

src/org/geometerplus/fbreader/formats/JavaEncodingCollection.java

@@ -22,12 +22,21 @@ package org.geometerplus.fbreader.formats;
 import java.nio.charset.Charset;
 
 public final class JavaEncodingCollection extends FilteredEncodingCollection {
-	public JavaEncodingCollection() {
+	private volatile static JavaEncodingCollection ourInstance;
+
+	public static JavaEncodingCollection Instance() {
+		if (ourInstance == null) {
+			ourInstance = new JavaEncodingCollection();
+		}
+		return ourInstance;
+	}
+
+	private JavaEncodingCollection() {
 		super();
 	}
 
 	@Override
-	protected boolean isEncodingSupported(String name) {
+	public boolean isEncodingSupported(String name) {
 		try {
 			return Charset.forName(name) != null;
 		} catch (Exception e) {

src/org/geometerplus/fbreader/formats/NativeFormatPlugin.java

@@ -105,6 +105,6 @@ public class NativeFormatPlugin extends FormatPlugin {
 	@Override
 	public EncodingCollection supportedEncodings() {
 		// TODO: implement
-		return new JavaEncodingCollection();
+		return JavaEncodingCollection.Instance();
 	}
 }

src/org/geometerplus/fbreader/formats/pdb/MobipocketPlugin.java

@@ -246,6 +246,6 @@ public class MobipocketPlugin extends JavaFormatPlugin {
 
 	@Override
 	public EncodingCollection supportedEncodings() {
-		return new JavaEncodingCollection();
+		return JavaEncodingCollection.Instance();
 	}
 }