diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/OFBitMask512.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/OFBitMask512.java
new file mode 100644
index 0000000..e05df4c
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/OFBitMask512.java
@@ -0,0 +1,205 @@
+package org.projectfloodlight.openflow.types;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+
+import com.google.common.hash.PrimitiveSink;
+
+public class OFBitMask512 implements OFValueType<OFBitMask512> {
+
+    static final int LENGTH = 64;
+
+    private final long raw1;
+    private final long raw2;
+    private final long raw3;
+    private final long raw4;
+    private final long raw5;
+    private final long raw6;
+    private final long raw7;
+    private final long raw8;
+
+    public static final OFBitMask512 ALL = new OFBitMask512(-1, -1, -1, -1,
+                                                            -1, -1, -1, -1);
+    public static final OFBitMask512 NONE = new OFBitMask512(0, 0, 0, 0,
+                                                             0, 0, 0, 0);
+
+    public static final OFBitMask512 NO_MASK = ALL;
+    public static final OFBitMask512 FULL_MASK = NONE;
+
+    private OFBitMask512(long raw1, long raw2, long raw3, long raw4,
+                         long raw5, long raw6, long raw7, long raw8) {
+        this.raw1 = raw1;
+        this.raw2 = raw2;
+        this.raw3 = raw3;
+        this.raw4 = raw4;
+        this.raw5 = raw5;
+        this.raw6 = raw6;
+        this.raw7 = raw7;
+        this.raw8 = raw8;
+    }
+
+    public static OFBitMask512 of(long raw1, long raw2, long raw3, long raw4,
+                                  long raw5, long raw6, long raw7, long raw8) {
+        if (raw1 == -1 && raw2 == -1 && raw3 == -1 && raw4 == -1
+                && raw5 == -1 && raw6 == -1 && raw7 == -1 && raw8 == -1)
+            return ALL;
+        if (raw1 == 0 && raw2 == 0 && raw3 == 0 && raw4 == 0
+                && raw5 == 0 && raw6 == 0 && raw7 == 0 && raw8 == 0)
+            return NONE;
+        return new OFBitMask512(raw1, raw2, raw3, raw4, raw5, raw6, raw7, raw8);
+    }
+
+    @Override
+    public int getLength() {
+        return LENGTH;
+    }
+
+    @Override
+    public OFBitMask512 applyMask(OFBitMask512 mask) {
+        return of(this.raw1 & mask.raw1, this.raw2 & mask.raw2,
+                  this.raw3 & mask.raw3, this.raw4 & mask.raw4,
+                  this.raw5 & mask.raw5, this.raw6 & mask.raw6,
+                  this.raw7 & mask.raw7, this.raw8 & mask.raw8);
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + (int) (raw1 ^ (raw1 >>> 32));
+        result = prime * result + (int) (raw2 ^ (raw2 >>> 32));
+        result = prime * result + (int) (raw3 ^ (raw3 >>> 32));
+        result = prime * result + (int) (raw4 ^ (raw4 >>> 32));
+        result = prime * result + (int) (raw5 ^ (raw5 >>> 32));
+        result = prime * result + (int) (raw6 ^ (raw6 >>> 32));
+        result = prime * result + (int) (raw7 ^ (raw7 >>> 32));
+        result = prime * result + (int) (raw8 ^ (raw8 >>> 32));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj == null) return false;
+        if (getClass() != obj.getClass()) return false;
+        OFBitMask512 other = (OFBitMask512) obj;
+        if (raw1 != other.raw1) return false;
+        if (raw2 != other.raw2) return false;
+        if (raw3 != other.raw3) return false;
+        if (raw4 != other.raw4) return false;
+        if (raw5 != other.raw5) return false;
+        if (raw6 != other.raw6) return false;
+        if (raw7 != other.raw7) return false;
+        if (raw8 != other.raw8) return false;
+        return true;
+    }
+
+    protected static boolean isBitOn(long raw1, long raw2, long raw3, long raw4,
+                                     long raw5, long raw6, long raw7, long raw8, int bit) {
+        if (bit < 0 || bit >= 512)
+            throw new IndexOutOfBoundsException();
+        long word;
+        if (bit < 64) {
+            word = raw8;
+        } else if (bit < 128) {
+            word = raw7;
+            bit -= 64;
+        } else if (bit < 128) {
+            word = raw6;
+            bit -= 128;
+        } else if (bit < 128) {
+            word = raw5;
+            bit -= 192;
+        } else if (bit < 128) {
+            word = raw4;
+            bit -= 256;
+        } else if (bit < 128) {
+            word = raw3;
+            bit -= 320;
+        } else if (bit < 128) {
+            word = raw2;
+            bit -= 384;
+        } else {
+            word = raw1; // ports -512
+            bit -= 448;
+        }
+        return (word & ((long)1 << bit)) != 0;
+    }
+
+    public void write64Bytes(ChannelBuffer cb) {
+        cb.writeLong(raw1);
+        cb.writeLong(raw2);
+        cb.writeLong(raw3);
+        cb.writeLong(raw4);
+        cb.writeLong(raw5);
+        cb.writeLong(raw6);
+        cb.writeLong(raw7);
+        cb.writeLong(raw8);
+    }
+
+    public static OFBitMask512 read64Bytes(ChannelBuffer cb) {
+        long raw1 = cb.readLong();
+        long raw2 = cb.readLong();
+        long raw3 = cb.readLong();
+        long raw4 = cb.readLong();
+        long raw5 = cb.readLong();
+        long raw6 = cb.readLong();
+        long raw7 = cb.readLong();
+        long raw8 = cb.readLong();
+        return of(raw1, raw2, raw3, raw4, raw5, raw6, raw7, raw8);
+    }
+
+    public boolean isOn(int bit) {
+        return isBitOn(raw1, raw2, raw3, raw4, raw5, raw6, raw7, raw8, bit);
+    }
+
+    @Override
+    public String toString() {
+        return (String.format("%64s", Long.toBinaryString(raw8))
+                + String.format("%64s", Long.toBinaryString(raw7))
+                + String.format("%64s", Long.toBinaryString(raw6))
+                + String.format("%64s", Long.toBinaryString(raw5))
+                + String.format("%64s", Long.toBinaryString(raw4))
+                + String.format("%64s", Long.toBinaryString(raw3))
+                + String.format("%64s", Long.toBinaryString(raw2))
+                + String.format("%64s", Long.toBinaryString(raw1))).replaceAll(" ", "0");
+    }
+
+    @Override
+    public int compareTo(OFBitMask512 o) {
+        long c = this.raw1 - o.raw1;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw2 - o.raw2;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw3 - o.raw3;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw4 - o.raw4;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw5 - o.raw5;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw6 - o.raw6;
+        if (c != 0)
+            return Long.signum(c);
+        c = this.raw7 - o.raw7;
+        if (c != 0)
+            return Long.signum(c);
+        return Long.signum(this.raw8 - o.raw8);
+    }
+
+    @Override
+    public void putTo(PrimitiveSink sink) {
+        sink.putLong(raw1);
+        sink.putLong(raw2);
+        sink.putLong(raw3);
+        sink.putLong(raw4);
+        sink.putLong(raw5);
+        sink.putLong(raw6);
+        sink.putLong(raw7);
+        sink.putLong(raw8);
+    }
+
+}