diff --git a/lib/java/README.md b/lib/java/README.md
index 1e4aed2..cdd4059 100644
--- a/lib/java/README.md
+++ b/lib/java/README.md
@@ -161,3 +161,12 @@
 
 Gradle
 http://gradle.org/
+
+# Breaking Changes
+
+## 0.12.0
+
+The access modifier of the AutoExpandingBuffer class has been changed from
+public to default (package) and will no longer be accessible by third-party
+libraries.
+
diff --git a/lib/java/src/org/apache/thrift/transport/AutoExpandingBuffer.java b/lib/java/src/org/apache/thrift/transport/AutoExpandingBuffer.java
index b02905f..fc3aa92 100644
--- a/lib/java/src/org/apache/thrift/transport/AutoExpandingBuffer.java
+++ b/lib/java/src/org/apache/thrift/transport/AutoExpandingBuffer.java
@@ -18,6 +18,8 @@
  */
 package org.apache.thrift.transport;
 
+import java.util.Arrays;
+
 /**
  * Helper class that wraps a byte[] so that it can expand and be reused. Users
  * should call resizeIfNecessary to make sure the buffer has suitable capacity,
@@ -25,28 +27,24 @@
  * rate slightly faster than the requested capacity with the (untested)
  * objective of avoiding expensive buffer allocations and copies.
  */
-public class AutoExpandingBuffer {
+class AutoExpandingBuffer {
   private byte[] array;
 
-  private final double growthCoefficient;
-
-  public AutoExpandingBuffer(int initialCapacity, double growthCoefficient) {
-    if (growthCoefficient < 1.0) {
-      throw new IllegalArgumentException("Growth coefficient must be >= 1.0");
-    }
-    array = new byte[initialCapacity];
-    this.growthCoefficient = growthCoefficient;
+  public AutoExpandingBuffer(int initialCapacity) {
+    this.array = new byte[initialCapacity];
   }
 
   public void resizeIfNecessary(int size) {
-    if (array.length < size) {
-      byte[] newBuf = new byte[(int)(size * growthCoefficient)];
-      System.arraycopy(array, 0, newBuf, 0, array.length);
-      array = newBuf;
+    final int currentCapacity = this.array.length;
+    if (currentCapacity < size) {
+      // Increase by a factor of 1.5x
+      int growCapacity = currentCapacity + (currentCapacity >> 1);
+      int newCapacity = Math.max(growCapacity, size);
+      this.array = Arrays.copyOf(array, newCapacity);
     }
   }
 
   public byte[] array() {
-    return array;
+    return this.array;
   }
 }
diff --git a/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferReadTransport.java b/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferReadTransport.java
index 081bc48..a28d254 100644
--- a/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferReadTransport.java
+++ b/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferReadTransport.java
@@ -28,8 +28,8 @@
   private int pos = 0;
   private int limit = 0;
 
-  public AutoExpandingBufferReadTransport(int initialCapacity, double overgrowthCoefficient) {
-    this.buf = new AutoExpandingBuffer(initialCapacity, overgrowthCoefficient);
+  public AutoExpandingBufferReadTransport(int initialCapacity) {
+    this.buf = new AutoExpandingBuffer(initialCapacity);
   }
 
   public void fill(TTransport inTrans, int length) throws TTransportException {
diff --git a/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferWriteTransport.java b/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferWriteTransport.java
index 9b35693..ad2ec55 100644
--- a/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferWriteTransport.java
+++ b/lib/java/src/org/apache/thrift/transport/AutoExpandingBufferWriteTransport.java
@@ -26,8 +26,8 @@
   private final AutoExpandingBuffer buf;
   private int pos;
 
-  public AutoExpandingBufferWriteTransport(int initialCapacity, double growthCoefficient) {
-    this.buf = new AutoExpandingBuffer(initialCapacity, growthCoefficient);
+  public AutoExpandingBufferWriteTransport(int initialCapacity) {
+    this.buf = new AutoExpandingBuffer(initialCapacity);
     this.pos = 0;
   }
 
diff --git a/lib/java/src/org/apache/thrift/transport/TFastFramedTransport.java b/lib/java/src/org/apache/thrift/transport/TFastFramedTransport.java
index d265600..891d798 100644
--- a/lib/java/src/org/apache/thrift/transport/TFastFramedTransport.java
+++ b/lib/java/src/org/apache/thrift/transport/TFastFramedTransport.java
@@ -106,8 +106,8 @@
     this.underlying = underlying;
     this.maxLength = maxLength;
     this.initialBufferCapacity = initialBufferCapacity;
-    writeBuffer = new AutoExpandingBufferWriteTransport(initialBufferCapacity, 1.5);
-    readBuffer = new AutoExpandingBufferReadTransport(initialBufferCapacity, 1.5);
+    writeBuffer = new AutoExpandingBufferWriteTransport(initialBufferCapacity);
+    readBuffer = new AutoExpandingBufferReadTransport(initialBufferCapacity);
   }
 
   @Override
@@ -167,7 +167,7 @@
   }
 
   public void clear() {
-    readBuffer = new AutoExpandingBufferReadTransport(initialBufferCapacity, 1.5);
+    readBuffer = new AutoExpandingBufferReadTransport(initialBufferCapacity);
   }
 
   @Override
diff --git a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBuffer.java b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBuffer.java
index 337dcf8..c353489 100644
--- a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBuffer.java
+++ b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBuffer.java
@@ -23,7 +23,7 @@
 public class TestAutoExpandingBuffer extends TestCase {
   public void testExpands() throws Exception {
     // has expected initial capacity
-    AutoExpandingBuffer b = new AutoExpandingBuffer(10, 1.5);
+    AutoExpandingBuffer b = new AutoExpandingBuffer(10);
     assertEquals(10, b.array().length);
 
     // doesn't shrink
diff --git a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferReadTransport.java b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferReadTransport.java
index 2e1f947..83ebc2d 100644
--- a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferReadTransport.java
+++ b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferReadTransport.java
@@ -32,7 +32,7 @@
   }
 
   public void testIt() throws Exception {
-    AutoExpandingBufferReadTransport t = new AutoExpandingBufferReadTransport(150, 1.5);
+    AutoExpandingBufferReadTransport t = new AutoExpandingBufferReadTransport(150);
 
     TMemoryInputTransport membuf = new TMemoryInputTransport(HUNDRED_BYTES);
 
diff --git a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferWriteTransport.java b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferWriteTransport.java
index d5f239d..6b04feb 100644
--- a/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferWriteTransport.java
+++ b/lib/java/test/org/apache/thrift/transport/TestAutoExpandingBufferWriteTransport.java
@@ -25,7 +25,7 @@
 public class TestAutoExpandingBufferWriteTransport extends TestCase {
 
   public void testIt() throws Exception {
-    AutoExpandingBufferWriteTransport t = new AutoExpandingBufferWriteTransport(1, 1.5);
+    AutoExpandingBufferWriteTransport t = new AutoExpandingBufferWriteTransport(1);
     assertEquals(1, t.getBuf().array().length);
     byte[] b1 = new byte[]{1,2,3};
     t.write(b1);