Index: modules/luni/src/main/java/java/io/ObjectOutputStream.java =================================================================== --- modules/luni/src/main/java/java/io/ObjectOutputStream.java (revision 406859) +++ modules/luni/src/main/java/java/io/ObjectOutputStream.java (working copy) @@ -794,6 +794,11 @@ * If an IO error occurs */ public void useProtocolVersion(int version) throws IOException { + if (version != ObjectStreamConstants.PROTOCOL_VERSION_1 + && version != ObjectStreamConstants.PROTOCOL_VERSION_2) { + throw new IllegalArgumentException(org.apache.harmony.luni.util.Msg + .getString("K00b3", version)); //$NON-NLS-1$ + } protocolVersion = version; }