Fix build failure.

Author: js-labs

src/main/java/org/jsl/collider/DataBlock.java

@@ -21,7 +21,7 @@
 
 import java.nio.ByteBuffer;
 
-class DataBlock
+public class DataBlock
 {
     public DataBlock next;
     public final ByteBuffer wr;

src/main/java/org/jsl/collider/DataBlockCache.java

@@ -24,7 +24,7 @@
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-class DataBlockCache
+public class DataBlockCache
 {
     private final boolean m_useDirectBuffers;
     private final int m_blockSize;