perf(java): Add ClassInfo ClassBytes generation conditions. (#1667)

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## What does this PR do?

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`ClassInfo#classNameBytes` and `ClassInfo#packageNameBytes` are only
used when `classInfo.classId == NO_CLASS_ID && !metaContextShareEnabled`

```java
public void writeClass(MemoryBuffer buffer, ClassInfo classInfo) {
  if (classInfo.classId == NO_CLASS_ID) { // no class id provided.
    // use classname
    if (metaContextShareEnabled) {
      buffer.writeByte(USE_CLASS_VALUE_FLAG);
      // FIXME(chaokunyang) Register class but not register serializer can't be used with
      //  meta share mode, because no class def are sent to peer.
      writeClassWithMetaShare(buffer, classInfo);
    } else {
      // if it's null, it's a bug.
      assert classInfo.packageNameBytes != null;
      metaStringResolver.writeMetaStringBytesWithFlag(buffer, classInfo.packageNameBytes);
      assert classInfo.classNameBytes != null;
      metaStringResolver.writeMetaStringBytes(buffer, classInfo.classNameBytes);
    }
  } else {
    // use classId
    buffer.writeVarUint32(classInfo.classId << 1);
  }
}
```


## Related issues

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## Does this PR introduce any user-facing change?

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- [ ] Does this PR introduce any public API change?
- [ ] Does this PR introduce any binary protocol compatibility change?


## Benchmark

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---------

Signed-off-by: LiangliangSui <[email protected]>

java/fury-core/src/main/java/org/apache/fury/meta/Encoders.java

@@ -36,8 +36,10 @@
 
 /** A class used to encode package/class/field name. */
 public class Encoders {
-  public static final MetaStringEncoder PACKAGE_ENCODER = new MetaStringEncoder('.', '_');
-  public static final MetaStringDecoder PACKAGE_DECODER = new MetaStringDecoder('.', '_');
+  public static final MetaStringEncoder GENERIC_ENCODER = new MetaStringEncoder('.', '_');
+  public static final MetaStringDecoder GENERIC_DECODER = new MetaStringDecoder('.', '_');
+  public static final MetaStringEncoder PACKAGE_ENCODER = GENERIC_ENCODER;
+  public static final MetaStringDecoder PACKAGE_DECODER = GENERIC_DECODER;
   public static final MetaStringEncoder TYPE_NAME_ENCODER = new MetaStringEncoder('$', '_');
   public static final MetaStringDecoder TYPE_NAME_DECODER = new MetaStringDecoder('$', '_');
   public static final String ARRAY_PREFIX = "1";

java/fury-core/src/main/java/org/apache/fury/resolver/ClassInfo.java

@@ -19,8 +19,8 @@
 
 package org.apache.fury.resolver;
 
+import static org.apache.fury.meta.Encoders.GENERIC_ENCODER;
 import static org.apache.fury.meta.Encoders.PACKAGE_ENCODER;
-import static org.apache.fury.meta.Encoders.TYPE_NAME_ENCODER;
 
 import org.apache.fury.collection.Tuple2;
 import org.apache.fury.config.Language;
@@ -82,18 +82,23 @@ public class ClassInfo {
     if (cls != null && classResolver.getFury().getLanguage() != Language.JAVA) {
       this.fullClassNameBytes =
           metaStringResolver.getOrCreateMetaStringBytes(
-              PACKAGE_ENCODER.encode(cls.getName(), Encoding.UTF_8));
+              GENERIC_ENCODER.encode(cls.getName(), Encoding.UTF_8));
     } else {
       this.fullClassNameBytes = null;
     }
+    // When `classId == ClassResolver.REPLACE_STUB_ID` was established,
+    // means only classes are serialized, not the instance. If we
+    // serialize such class only, we need to write classname bytes.
     if (cls != null
-        && (classId == ClassResolver.NO_CLASS_ID || classId == ClassResolver.REPLACE_STUB_ID)) {
+        && ((classId == ClassResolver.NO_CLASS_ID
+                && !classResolver.getFury().getConfig().isMetaShareEnabled())
+            || classId == ClassResolver.REPLACE_STUB_ID)) {
       // REPLACE_STUB_ID for write replace class in `ClassSerializer`.
       Tuple2<String, String> tuple2 = Encoders.encodePkgAndClass(cls);
       this.packageNameBytes =
-          metaStringResolver.getOrCreateMetaStringBytes(PACKAGE_ENCODER.encode(tuple2.f0));
+          metaStringResolver.getOrCreateMetaStringBytes(Encoders.encodePackage(tuple2.f0));
       this.classNameBytes =
-          metaStringResolver.getOrCreateMetaStringBytes(TYPE_NAME_ENCODER.encode(tuple2.f1));
+          metaStringResolver.getOrCreateMetaStringBytes(Encoders.encodeTypeName(tuple2.f1));
     } else {
       this.packageNameBytes = null;
       this.classNameBytes = null;

java/fury-core/src/main/java/org/apache/fury/resolver/ClassResolver.java

@@ -1701,7 +1701,7 @@ public Class<?> xreadClass(MemoryBuffer buffer) {
     Class<?> cls = classNameBytes2Class.get(byteString);
     if (cls == null) {
       Preconditions.checkNotNull(byteString);
-      String className = byteString.decode('.', '_');
+      String className = byteString.decode(Encoders.GENERIC_DECODER);
       cls = loadClass(className);
       classNameBytes2Class.put(byteString, cls);
     }

java/fury-core/src/main/java/org/apache/fury/resolver/MetaStringResolver.java

@@ -22,6 +22,7 @@
 import org.apache.fury.collection.LongMap;
 import org.apache.fury.collection.ObjectMap;
 import org.apache.fury.memory.MemoryBuffer;
+import org.apache.fury.meta.Encoders;
 import org.apache.fury.meta.MetaString;
 
 /**
@@ -109,7 +110,7 @@ public String readMetaString(MemoryBuffer buffer) {
     String str = metaStringBytes2StringMap.get(byteString);
     if (str == null) {
       // TODO support meta string in other languages.
-      str = byteString.decode('.', '_');
+      str = byteString.decode(Encoders.GENERIC_DECODER);
       metaStringBytes2StringMap.put(byteString, str);
     }
     return str;

java/fury-core/src/test/java/org/apache/fury/resolver/ClassInfoTest.java

@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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
+ *
+ *   http://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.apache.fury.resolver;
+
+import static org.testng.Assert.assertNotNull;
+import static org.testng.Assert.assertNull;
+
+import org.apache.fury.Fury;
+import org.apache.fury.config.Language;
+import org.testng.annotations.Test;
+
+public class ClassInfoTest {
+  @Test
+  public void testEncodePackageNameAndTypeName() {
+    Fury fury =
+        Fury.builder()
+            .withLanguage(Language.JAVA)
+            .requireClassRegistration(false)
+            .withMetaShare(true)
+            .build();
+    ClassInfo info = fury.getClassResolver().getClassInfo(org.apache.fury.test.bean.Foo.class);
+    assertNull(info.packageNameBytes);
+
+    Fury fury1 = Fury.builder().withLanguage(Language.JAVA).requireClassRegistration(false).build();
+    ClassInfo info1 = fury1.getClassResolver().getClassInfo(org.apache.fury.test.bean.Foo.class);
+    assertNotNull(info1.packageNameBytes);
+    assertNotNull(info1.classNameBytes);
+  }
+}