handle null lists

README.md

@@ -2,4 +2,8 @@
 
 This is an experimental pure Java implementation of Cap'n Proto.
 
-It doesn't do much yet.
+It doesn't do much yet.
+
+```
+make
+```

src/capnp/WireHelpers.java

@@ -29,6 +29,9 @@ class WireHelpers {
                                              int nestingLimit) {
 
         // TODO check for null, follow fars, nestingLimit
+        if (ref.isNull()) {
+            return new ListReader();
+        }
 
         ListPointer listPtr = new ListPointer(ref);
 

src/capnp/WirePointer.java

@@ -21,6 +21,10 @@ class WirePointer {
         this.buffer_offset = word.offset;
     }
 
+    public boolean isNull() {
+        return this.buffer.getLong(this.buffer_offset * 8) == 0;
+    }
+
     public int offset_and_kind() {
         return this.buffer.getInt(this.buffer_offset * 8);
     }

src/compiler/capnpc-java.c++

@@ -21,7 +21,10 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+
 // This program is a code generator plugin for `capnp compile` which generates java code.
+// It is a modified version of the C++ code generator plugin, capnpc-c++.
+
 
 #include <capnp/schema.capnp.h>
 #include "capnp/serialize.h"