move pool reference from BufferRecycler to IOContext

src/main/java/com/fasterxml/jackson/core/JsonFactory.java

@@ -2140,26 +2140,13 @@ protected JsonGenerator _decorate(JsonGenerator g) {
     /**********************************************************
      */
 
-    /**
-     * Method used by factory to create buffer recycler instances
-     * for parsers and generators.
-     *<p>
-     * Note: only public to give access for {@code ObjectMapper}
-     *
-     * @return Buffer recycler instance to use
-     */
-    public BufferRecycler _getBufferRecycler()
-    {
-        return _getBufferRecyclerPool().acquireBufferRecycler();
-    }
-
     /**
      * Accessor for getting access to {@link BufferRecyclerPool} for getting
      * {@link BufferRecycler} instance to use.
      *
      * @since 2.16
      */
-    public BufferRecyclerPool _getBufferRecyclerPool() {
+    private BufferRecyclerPool _getBufferRecyclerPool() {
         // 23-Apr-2015, tatu: Let's allow disabling of buffer recycling
         //   scheme, for cases where it is considered harmful (possibly
         //   on Android, for example)
@@ -2183,8 +2170,9 @@ protected IOContext _createContext(ContentReference contentRef, boolean resource
         if (contentRef == null) {
             contentRef = ContentReference.unknown();
         }
+        BufferRecyclerPool pool = _getBufferRecyclerPool();
         return new IOContext(_streamReadConstraints, _streamWriteConstraints, _errorReportConfiguration,
-                _getBufferRecycler(), contentRef, resourceManaged);
+                pool.acquireBufferRecycler(), pool, contentRef, resourceManaged);
     }
 
     /**
@@ -2199,8 +2187,9 @@ protected IOContext _createContext(ContentReference contentRef, boolean resource
      */
     @Deprecated // @since 2.13
     protected IOContext _createContext(Object rawContentRef, boolean resourceManaged) {
+        BufferRecyclerPool pool = _getBufferRecyclerPool();
         return new IOContext(_streamReadConstraints, _streamWriteConstraints, _errorReportConfiguration,
-                _getBufferRecycler(),
+                pool.acquireBufferRecycler(), pool,
                 _createContentReference(rawContentRef),
                 resourceManaged);
     }
@@ -2218,8 +2207,9 @@ protected IOContext _createContext(Object rawContentRef, boolean resourceManaged
     protected IOContext _createNonBlockingContext(Object srcRef) {
         // [jackson-core#479]: allow recycling for non-blocking parser again
         // now that access is thread-safe
+        BufferRecyclerPool pool = _getBufferRecyclerPool();
         return new IOContext(_streamReadConstraints, _streamWriteConstraints, _errorReportConfiguration,
-                _getBufferRecycler(),
+                pool.acquireBufferRecycler(), pool,
                 _createContentReference(srcRef),
                 false);
     }

src/main/java/com/fasterxml/jackson/core/io/IOContext.java

@@ -5,6 +5,7 @@
 import com.fasterxml.jackson.core.StreamReadConstraints;
 import com.fasterxml.jackson.core.StreamWriteConstraints;
 import com.fasterxml.jackson.core.util.BufferRecycler;
+import com.fasterxml.jackson.core.util.BufferRecyclerPool;
 import com.fasterxml.jackson.core.util.ReadConstrainedTextBuffer;
 import com.fasterxml.jackson.core.util.TextBuffer;
 
@@ -64,6 +65,8 @@ public class IOContext implements AutoCloseable
      */
     protected final BufferRecycler _bufferRecycler;
 
+    private final BufferRecyclerPool _bufferRecyclerPool;
+
     /**
      * @since 2.15
      */
@@ -133,19 +136,21 @@ public class IOContext implements AutoCloseable
      * @param src constraints for streaming reads
      * @param swc constraints for streaming writes
      * @param br BufferRecycler to use, if any ({@code null} if none)
+     * @param brPool BufferRecyclerPool the pool from where the BufferRecycler has been acquired, if any ({@code null} if none)
      * @param contentRef Input source reference for location reporting
      * @param managedResource Whether input source is managed (owned) by Jackson library
      * @param erc Error report configuration to use
      *
      * @since 2.16
      */
     public IOContext(StreamReadConstraints src, StreamWriteConstraints swc, ErrorReportConfiguration erc,
-            BufferRecycler br, ContentReference contentRef, boolean managedResource)
+            BufferRecycler br, BufferRecyclerPool brPool, ContentReference contentRef, boolean managedResource)
     {
         _streamReadConstraints = src;
         _streamWriteConstraints = swc;
         _errorReportConfiguration = erc;
         _bufferRecycler = br;
+        _bufferRecyclerPool = brPool;
         _contentReference = contentRef;
         _sourceRef = contentRef.getRawContent();
         _managedResource = managedResource;
@@ -168,7 +173,7 @@ public IOContext(StreamReadConstraints src, BufferRecycler br,
                      ContentReference contentRef, boolean managedResource)
     {
         this(src, StreamWriteConstraints.defaults(), ErrorReportConfiguration.defaults(),
-                br, contentRef, managedResource);
+                br, null, contentRef, managedResource);
     }
 
     /**
@@ -186,7 +191,7 @@ public IOContext(StreamReadConstraints src, BufferRecycler br,
     public IOContext(BufferRecycler br, ContentReference contentRef, boolean managedResource)
     {
         this(StreamReadConstraints.defaults(), StreamWriteConstraints.defaults(), ErrorReportConfiguration.defaults(),
-                br, contentRef, managedResource);
+                br, null, contentRef, managedResource);
     }
 
     @Deprecated // since 2.13
@@ -464,7 +469,9 @@ private IllegalArgumentException wrongBuf() {
     @Override
     public void close() {
         if (!_closed) {
-            _bufferRecycler.release();
+            if (_bufferRecyclerPool != null) {
+                _bufferRecycler.release(_bufferRecyclerPool);
+            }
             _closed = true;
         }
     }

src/main/java/com/fasterxml/jackson/core/util/BufferRecycler.java

@@ -86,8 +86,6 @@ public class BufferRecycler
     // Note: changed from simple array in 2.10:
     protected final AtomicReferenceArray<char[]> _charBuffers;
 
-    private BufferRecyclerPool _pool;
-
     /*
     /**********************************************************
     /* Construction
@@ -197,34 +195,11 @@ protected int charBufferLength(int ix) {
     protected char[] calloc(int size) { return new char[size]; }
 
     /**
-     * Method called by owner of this recycler instance, to provide reference to
-     * {@link BufferRecyclerPool} into which instance is to be released (if any)
+     * Method called when owner of this recycler no longer wishes use it.
      *
      * @since 2.16
      */
-    BufferRecycler withPool(BufferRecyclerPool pool) {
-        if (this._pool != null) {
-            throw new IllegalStateException("BufferRecycler already linked to pool: "+pool);
-        }
-        // assign to pool to which this BufferRecycler belongs in order to release it
-        // to the same pool when the work will be completed
-        _pool = Objects.requireNonNull(pool);
-        return this;
-    }
-
-    /**
-     * Method called when owner of this recycler no longer wishes use it; this should
-     * return it to pool passed via {@code withPool()} (if any).
-     *
-     * @since 2.16
-     */
-    public void release() {
-        if (_pool != null) {
-            BufferRecyclerPool tmpPool = _pool;
-            // nullify the reference to the pool in order to avoid the risk of releasing
-            // the same BufferRecycler more than once, thus compromising the pool integrity
-            _pool = null;
-            tmpPool.releaseBufferRecycler(this);
-        }
+    public void release(BufferRecyclerPool pool) {
+        pool.releaseBufferRecycler(this);
     }
 }

src/main/java/com/fasterxml/jackson/core/util/BufferRecyclerPool.java

@@ -266,7 +266,7 @@ public BufferRecycler acquireBufferRecycler() {
             if (bufferRecycler == null) {
                 bufferRecycler = new BufferRecycler();
             }
-            return bufferRecycler.withPool(this);
+            return bufferRecycler;
         }
 
         @Override
@@ -333,7 +333,7 @@ protected Object readResolve() {
 
         @Override
         public BufferRecycler acquireBufferRecycler() {
-            return _getRecycler().withPool(this);
+            return _getRecycler();
         }
 
         private BufferRecycler _getRecycler() {
@@ -448,7 +448,7 @@ public BufferRecycler acquireBufferRecycler() {
             if (bufferRecycler == null) {
                 bufferRecycler = new BufferRecycler();
             }
-            return bufferRecycler.withPool(this);
+            return bufferRecycler;
         }
 
         @Override

src/test/java/com/fasterxml/jackson/core/io/BufferRecyclerPoolTest.java

@@ -33,6 +33,10 @@ public void testBounded() throws Exception {
         checkBufferRecyclerPoolImpl(BufferRecyclerPool.BoundedPool.nonShared(1), true);
     }
 
+    public void testPluggingPool() throws Exception {
+        checkBufferRecyclerPoolImpl(new TestPool(), true);
+    }
+
     private void checkBufferRecyclerPoolImpl(BufferRecyclerPool pool, boolean checkPooledResource) throws Exception {
         JsonFactory jsonFactory = JsonFactory.builder()
                 .bufferRecyclerPool(pool)
@@ -45,7 +49,7 @@ private void checkBufferRecyclerPoolImpl(BufferRecyclerPool pool, boolean checkP
             try {
                 assertSame(usedBufferRecycler, pooledBufferRecycler);
             } finally {
-                pooledBufferRecycler.release();
+                pooledBufferRecycler.release(pool);
             }
         }
     }
@@ -75,4 +79,23 @@ private static class NopOutputStream extends OutputStream {
         @Override
         public void write(byte[] b, int offset, int len) throws IOException { size += len; }
     }
+
+    class TestPool implements BufferRecyclerPool {
+        private BufferRecycler bufferRecycler;
+
+        @Override
+        public BufferRecycler acquireBufferRecycler() {
+            if (bufferRecycler != null) {
+                BufferRecycler tmp = bufferRecycler;
+                this.bufferRecycler = null;
+                return tmp;
+            }
+            return new BufferRecycler();
+        }
+
+        @Override
+        public void releaseBufferRecycler(BufferRecycler recycler) {
+            this.bufferRecycler = recycler;
+        }
+    }
 }

src/test/java/com/fasterxml/jackson/core/io/TestIOContext.java

@@ -13,7 +13,7 @@ public void testAllocations() throws Exception
         IOContext ctxt = new IOContext(StreamReadConstraints.defaults(),
                 StreamWriteConstraints.defaults(),
                 ErrorReportConfiguration.defaults(),
-                new BufferRecycler(),
+                new BufferRecycler(), null,
                 ContentReference.rawReference("N/A"), true);
 
         /* I/O Read buffer */

src/test/java/com/fasterxml/jackson/core/testsupport/TestSupport.java

@@ -45,6 +45,6 @@ private static IOContext testIOContext(StreamReadConstraints src,
             StreamWriteConstraints swc,
             ErrorReportConfiguration erc) {
         return new IOContext(src, swc, erc,
-                new BufferRecycler(), ContentReference.unknown(), false);
+                new BufferRecycler(), null, ContentReference.unknown(), false);
     }
 }

src/test/java/com/fasterxml/jackson/core/util/ReadConstrainedTextBufferTest.java

@@ -64,7 +64,7 @@ private static IOContext makeConstrainedContext(int maxStringLen) {
                 constraints,
                 StreamWriteConstraints.defaults(),
                 ErrorReportConfiguration.defaults(),
-                new BufferRecycler(),
+                new BufferRecycler(), null,
                 ContentReference.rawReference("N/A"), true);
     }
 }

src/test/java/com/fasterxml/jackson/core/write/WriterBasedJsonGeneratorTest.java

@@ -49,7 +49,7 @@ private IOContext _ioContext(StreamWriteConstraints swc) {
         return new IOContext(StreamReadConstraints.defaults(),
                 swc,
                 ErrorReportConfiguration.defaults(),
-                new BufferRecycler(),
+                new BufferRecycler(), null,
                 ContentReference.unknown(), true);
     }
 }