mojo: Validate fixed size array for the mojo java bindings.

mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java

Index: mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
diff --git a/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java b/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
index 8295c5eed3202d0a3efa2a81b6adbecdce7f280a..bb11efd35d2007e0a171b61105fbddf63a762d67 100644
--- a/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
+++ b/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
@@ -128,6 +128,21 @@ public class Decoder {
     }
 
     /**
+     * Deserializes a {@link DataHeader} of an array at the given offset.
+     *
+     * @param expectedLength the expected length of the array.
+     */
+    public DataHeader readArrayDataHeader(int expectedLength) {
+        DataHeader dataHeader = readDataHeader();
+        if (expectedLength != BindingsHelper.UNSPECIFIED_ARRAY_LENGTH
+                && dataHeader.numFields != expectedLength) {
+            throw new DeserializationException("Incorrect array length. Expected: " +
+                    expectedLength + ", but got: " + dataHeader.numFields + ".");
+        }
+        return dataHeader;
+    }
+
+    /**
      * Deserializes a byte at the given offset.
      */
     public byte readByte(int offset) {
@@ -195,12 +210,12 @@ public class Decoder {
     /**
      * Deserializes an array of boolean at the given offset.
      */
-    public boolean[] readBooleans(int offset) {
+    public boolean[] readBooleans(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         byte[] bytes = new byte[si.numFields + 7 / BindingsHelper.ALIGNMENT];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.get(bytes);
@@ -219,12 +234,12 @@ public class Decoder {
     /**
      * Deserializes an array of bytes at the given offset.
      */
-    public byte[] readBytes(int offset) {
+    public byte[] readBytes(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         byte[] result = new byte[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.get(result);
@@ -234,12 +249,12 @@ public class Decoder {
     /**
      * Deserializes an array of shorts at the given offset.
      */
-    public short[] readShorts(int offset) {
+    public short[] readShorts(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         short[] result = new short[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asShortBuffer().get(result);
@@ -249,12 +264,12 @@ public class Decoder {
     /**
      * Deserializes an array of ints at the given offset.
      */
-    public int[] readInts(int offset) {
+    public int[] readInts(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         int[] result = new int[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asIntBuffer().get(result);
@@ -264,12 +279,12 @@ public class Decoder {
     /**
      * Deserializes an array of floats at the given offset.
      */
-    public float[] readFloats(int offset) {
+    public float[] readFloats(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         float[] result = new float[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asFloatBuffer().get(result);
@@ -279,12 +294,12 @@ public class Decoder {
     /**
      * Deserializes an array of longs at the given offset.
      */
-    public long[] readLongs(int offset) {
+    public long[] readLongs(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         long[] result = new long[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asLongBuffer().get(result);
@@ -294,12 +309,12 @@ public class Decoder {
     /**
      * Deserializes an array of doubles at the given offset.
      */
-    public double[] readDoubles(int offset) {
+    public double[] readDoubles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         double[] result = new double[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asDoubleBuffer().get(result);
@@ -358,8 +373,7 @@ public class Decoder {
      *
      * @return a proxy to the service.
      */
-    public <P extends Proxy> P readServiceInterface(int offset,
-            Interface.Manager<?, P> manager) {
+    public <P extends Proxy> P readServiceInterface(int offset, Interface.Manager<?, P> manager) {
         MessagePipeHandle handle = readMessagePipeHandle(offset);
         if (!handle.isValid()) {
             return null;
@@ -382,7 +396,7 @@ public class Decoder {
      * Deserializes a string at the given offset.
      */
     public String readString(int offset) {
-        byte[] bytes = readBytes(offset);
+        byte[] bytes = readBytes(offset, BindingsHelper.UNSPECIFIED_ARRAY_LENGTH);
         if (bytes == null) {
             return null;
         }
@@ -392,12 +406,12 @@ public class Decoder {
     /**
      * Deserializes an array of |Handle| at the given offset.
      */
-    public Handle[] readHandles(int offset) {
+    public Handle[] readHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         Handle[] result = new Handle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readHandle(
@@ -409,12 +423,12 @@ public class Decoder {
     /**
      * Deserializes an array of |UntypedHandle| at the given offset.
      */
-    public UntypedHandle[] readUntypedHandles(int offset) {
+    public UntypedHandle[] readUntypedHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         UntypedHandle[] result = new UntypedHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readUntypedHandle(
@@ -426,12 +440,12 @@ public class Decoder {
     /**
      * Deserializes an array of |ConsumerHandle| at the given offset.
      */
-    public DataPipe.ConsumerHandle[] readConsumerHandles(int offset) {
+    public DataPipe.ConsumerHandle[] readConsumerHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         DataPipe.ConsumerHandle[] result = new DataPipe.ConsumerHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readConsumerHandle(
@@ -443,12 +457,12 @@ public class Decoder {
     /**
      * Deserializes an array of |ProducerHandle| at the given offset.
      */
-    public DataPipe.ProducerHandle[] readProducerHandles(int offset) {
+    public DataPipe.ProducerHandle[] readProducerHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         DataPipe.ProducerHandle[] result = new DataPipe.ProducerHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readProducerHandle(
@@ -461,12 +475,12 @@ public class Decoder {
     /**
      * Deserializes an array of |MessagePipeHandle| at the given offset.
      */
-    public MessagePipeHandle[] readMessagePipeHandles(int offset) {
+    public MessagePipeHandle[] readMessagePipeHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         MessagePipeHandle[] result = new MessagePipeHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readMessagePipeHandle(
@@ -479,12 +493,12 @@ public class Decoder {
     /**
      * Deserializes an array of |SharedBufferHandle| at the given offset.
      */
-    public SharedBufferHandle[] readSharedBufferHandles(int offset) {
+    public SharedBufferHandle[] readSharedBufferHandles(int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         SharedBufferHandle[] result = new SharedBufferHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readSharedBufferHandle(
@@ -497,13 +511,13 @@ public class Decoder {
     /**
      * Deserializes an array of |ServiceHandle| at the given offset.
      */
-    public <S extends Interface, P extends Proxy> S[] readServiceInterfaces(int offset,
-            Interface.Manager<S, P> manager) {
+    public <S extends Interface, P extends Proxy> S[] readServiceInterfaces(
+            int offset, Interface.Manager<S, P> manager, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         S[] result = manager.buildArray(si.numFields);
         for (int i = 0; i < result.length; ++i) {
             // This cast is necessary because java 6 doesn't handle wildcard correctly when using
@@ -519,12 +533,13 @@ public class Decoder {
     /**
      * Deserializes an array of |InterfaceRequest| at the given offset.
      */
-    public <I extends Interface> InterfaceRequest<I>[] readInterfaceRequests(int offset) {
+    public <I extends Interface> InterfaceRequest<I>[] readInterfaceRequests(
+            int offset, int expectedLength) {
         Decoder d = readPointer(offset);
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         @SuppressWarnings("unchecked")
         InterfaceRequest<I>[] result = new InterfaceRequest[si.numFields];
         for (int i = 0; i < result.length; ++i) {