diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Match.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Match.java
new file mode 100644
index 0000000..5e68de5
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Match.java
@@ -0,0 +1,207 @@
+package org.projectfloodlight.openflow.protocol.match;
+
+import org.projectfloodlight.openflow.protocol.OFObject;
+import org.projectfloodlight.openflow.types.Masked;
+import org.projectfloodlight.openflow.types.OFValueType;
+
+/**
+ * Generic interface for version-agnostic immutable Match structure.
+ * The Match structure is defined in the OpenFlow protocol, and it contains information on
+ * the fields to be matched in a specific flow record.
+ * This interface does not assume anything on the fields in the Match structure. If in
+ * some version, the match structure cannot handle a certain field, it may return <code>false</code>
+ * for <code>supports(...)</code> calls, and throw <code>UnsupportedOperationException</code> from all
+ * other methods in such cases.
+ * <br><br>
+ * On wildcards and masks:<br>
+ * This interface defines the following masking notations for fields:
+ * <ul>
+ * <li><b>Exact</b>: field is matched exactly against a single, fixed value (no mask, or mask is all ones).
+ * <li><b>Wildcarded</b>: field is not being matched. It is fully masked (mask=0) and any value of it
+ * will match the flow record having this match.
+ * <li><b>Partially masked</b>: field is matched using a specified mask which is neither 0 nor all ones. Mask can
+ * be either arbitrary or require some specific structure.
+ * </ul>
+ * Implementing classes may or may not support all types of these masking types. They may also support
+ * them in part. For example, OF1.0 supports exact match and (full) wildcarding for all fields, but it
+ * does only supports partial masking for IP source/destination fields, and this partial masking must be
+ * in the CIDR prefix format. Thus, OF1.0 implementation may throw <code>UnsupportedOperationException</code> if given
+ * in <code>setMaksed</code> an IP mask of, for example, 255.0.255.0, or if <code>setMasked</code> is called for any field
+ * which is not IP source/destination address.
+ * <br><br>
+ * On prerequisites:<br>
+ * From the OF1.1 spec, page 28, the OF1.0 spec failed to explicitly specify this, but it
+ * is the behavior of OF1.0 switches:
+ * "Protocol-specific fields within ofp_match will be ignored within a single table when
+ * the corresponding protocol is not specified in the match. The MPLS match fields will
+ * be ignored unless the Ethertype is specified as MPLS. Likewise, the IP header and
+ * transport header fields will be ignored unless the Ethertype is specified as either
+ * IPv4 or ARP. The tp_src and tp_dst fields will be ignored unless the network protocol
+ * specified is as TCP, UDP or SCTP. Fields that are ignored don�t need to be wildcarded
+ * and should be set to 0."
+ * <br><br>
+ * This interface uses generics to assure type safety in users code. However, implementing classes may have to suppress
+ * 'unchecked cast' warnings while making sure they correctly cast base on their implementation details.
+ *
+ * @author Yotam Harchol (yotam.harchol@bigswitch.com)
+ */
+public interface Match extends OFObject {
+
+    /**
+     * Returns a value for the given field if:
+     * <ul>
+     * <li>Field is supported
+     * <li>Field is not fully wildcarded
+     * <li>Prerequisites are ok
+     * </ul>
+     * If one of the above conditions does not hold, returns null. Value is returned masked if partially wildcarded.
+     *
+     * @param field Match field to retrieve
+     * @return Value of match field (may be masked), or <code>null</code> if field is one of the conditions above does not hold.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public <F extends OFValueType<F>> F get(MatchField<F> field) throws UnsupportedOperationException;
+
+    /**
+     * Returns the masked value for the given field from this match, along with the mask itself.
+     * Prerequisite: field is partially masked.
+     * If prerequisite is not met, a <code>null</code> is returned.
+     *
+     * @param field Match field to retrieve.
+     * @return Masked value of match field or null if no mask is set.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public <F extends OFValueType<F>> Masked<F> getMasked(MatchField<F> field) throws UnsupportedOperationException;
+
+    /**
+     * Returns true if and only if this match object supports the given match field.
+     *
+     * @param field Match field
+     * @return true if field is supported, false otherwise.
+     */
+    public boolean supports(MatchField<?> field);
+
+    /**
+     * Returns true if and only if this match object supports partially bitmasking of the given field.
+     * (note: not all possible values of this bitmask have to be acceptable)
+     *
+     * @param field Match field.
+     * @return true if field can be partially masked, false otherwise.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public boolean supportsMasked(MatchField<?> field) throws UnsupportedOperationException;
+
+    /**
+     * Returns true if and only if this field is currently specified in the match with an exact value and
+     * no mask. I.e., the specified match will only select packets that match the exact value of getValue(field).
+     *
+     * @param field Match field.
+     * @return true if field has a specific exact value, false if not.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public boolean isExact(MatchField<?> field) throws UnsupportedOperationException;
+
+    /**
+     * True if and only if this field is currently logically unspecified in the match, i.e, the
+     * value returned by getValue(f) has no impact on whether a packet will be selected
+     * by the match or not.
+     *
+     * @param field Match field.
+     * @return true if field is fully wildcarded, false if not.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public boolean isFullyWildcarded(MatchField<?> field) throws UnsupportedOperationException;
+
+    /**
+     * True if and only if this field is currently partially specified in the match, i.e, the
+     * match will only select packets that match (p.value & getMask(field)) == getValue(field),
+     * and getMask(field) != 0.
+     *
+     * @param field Match field.
+     * @return true if field is partially masked, false if not.
+     * @throws UnsupportedOperationException If field is not supported.
+     */
+    public boolean isPartiallyMasked(MatchField<?> field) throws UnsupportedOperationException;
+
+    /**
+     * Returns a builder to build new instances of this type of match object.
+     * @return Match builder
+     */
+    public Builder createBuilder();
+
+    /**
+     * Builder interface for Match objects.
+     * Builder is used to create new Match objects and it creates the match according to the version it
+     * corresponds to. The builder uses the same notation of wildcards and masks, and can also throw
+     * <code>UnsupportedOperationException</code> if it is asked to create some matching that is not supported in
+     * the version it represents.
+     *
+     * While used, MatchBuilder may not be consistent in terms of field prerequisites. However, user must
+     * solve these before using the generated Match object as these prerequisites should be enforced in the
+     * getters.
+     *
+     * @author Yotam Harchol (yotam.harchol@bigswitch.com)
+     */
+    interface Builder {
+        public <F extends OFValueType<F>> F get(MatchField<F> field) throws UnsupportedOperationException;
+
+        public <F extends OFValueType<F>> Masked<F> getMasked(MatchField<F> field) throws UnsupportedOperationException;
+
+        public boolean supports(MatchField<?> field);
+
+        public boolean supportsMasked(MatchField<?> field) throws UnsupportedOperationException;
+
+        public boolean isExact(MatchField<?> field) throws UnsupportedOperationException;
+
+        public boolean isFullyWildcarded(MatchField<?> field) throws UnsupportedOperationException;
+
+        public boolean isPartiallyMasked(MatchField<?> field) throws UnsupportedOperationException;
+
+        /**
+         * Sets a specific exact value for a field.
+         *
+         * @param field Match field to set.
+         * @param value Value of match field.
+         * @return the Builder instance used.
+         * @throws UnsupportedOperationException If field is not supported.
+         */
+        public <F extends OFValueType<F>> Builder setExact(MatchField<F> field, F value) throws UnsupportedOperationException;
+
+        /**
+         * Sets a masked value for a field.
+         *
+         * @param field Match field to set.
+         * @param value Value of field.
+         * @param mask Mask value.
+         * @return the Builder instance used.
+         * @throws UnsupportedOperationException If field is not supported, if field is supported but does not support masking, or if mask structure is not supported.
+         */
+        public <F extends OFValueType<F>> Builder setMasked(MatchField<F> field, F value, F mask) throws UnsupportedOperationException;
+
+        /**
+         * Sets a masked value for a field.
+         *
+         * @param field Match field to set.
+         * @param valueWithMask Compound Masked object contains the value and the mask.
+         * @return the Builder instance used.
+         * @throws UnsupportedOperationException If field is not supported, if field is supported but does not support masking, or if mask structure is not supported.
+         */
+        public <F extends OFValueType<F>> Builder setMasked(MatchField<F> field, Masked<F> valueWithMask) throws UnsupportedOperationException;
+
+        /**
+         * Unsets any value given for the field and wildcards it so that it matches any value.
+         *
+         * @param field Match field to unset.
+         * @return the Builder instance used.
+         * @throws UnsupportedOperationException If field is not supported.
+         */
+        public <F extends OFValueType<F>> Builder wildcard(MatchField<F> field) throws UnsupportedOperationException;
+
+        /**
+         * Returns the match created by this builder.
+         *
+         * @return a Match object.
+         */
+        public Match build();
+    }
+}
\ No newline at end of file
diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchField.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchField.java
new file mode 100644
index 0000000..333d25d
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchField.java
@@ -0,0 +1,156 @@
+package org.projectfloodlight.openflow.protocol.match;
+
+import org.projectfloodlight.openflow.types.ArpOpcode;
+import org.projectfloodlight.openflow.types.EthType;
+import org.projectfloodlight.openflow.types.ICMPv4Code;
+import org.projectfloodlight.openflow.types.ICMPv4Type;
+import org.projectfloodlight.openflow.types.IPv4;
+import org.projectfloodlight.openflow.types.IPv6;
+import org.projectfloodlight.openflow.types.IPv6FlowLabel;
+import org.projectfloodlight.openflow.types.IpDscp;
+import org.projectfloodlight.openflow.types.IpEcn;
+import org.projectfloodlight.openflow.types.IpProtocol;
+import org.projectfloodlight.openflow.types.MacAddress;
+import org.projectfloodlight.openflow.types.OFMetadata;
+import org.projectfloodlight.openflow.types.OFPort;
+import org.projectfloodlight.openflow.types.OFValueType;
+import org.projectfloodlight.openflow.types.TransportPort;
+import org.projectfloodlight.openflow.types.VlanPcp;
+import org.projectfloodlight.openflow.types.VlanVid;
+
+@SuppressWarnings("unchecked")
+public class MatchField<F extends OFValueType<F>> {
+    private final String name;
+    public final MatchFields id;
+    private final Prerequisite<?>[] prerequisites;
+
+    private MatchField(final String name, final MatchFields id, Prerequisite<?>... prerequisites) {
+        this.name = name;
+        this.id = id;
+        this.prerequisites = prerequisites;
+    }
+
+    public final static MatchField<OFPort> IN_PORT =
+            new MatchField<OFPort>("in_port", MatchFields.IN_PORT);
+
+    public final static MatchField<OFPort> IN_PHY_PORT =
+            new MatchField<OFPort>("in_phy_port", MatchFields.IN_PHY_PORT,
+                    new Prerequisite<OFPort>(MatchField.IN_PORT));
+
+    public final static MatchField<OFMetadata> METADATA =
+            new MatchField<OFMetadata>("metadata", MatchFields.METADATA);
+
+    public final static MatchField<MacAddress> ETH_DST =
+            new MatchField<MacAddress>("eth_dst", MatchFields.ETH_DST);
+
+    public final static MatchField<MacAddress> ETH_SRC =
+            new MatchField<MacAddress>("eth_src", MatchFields.ETH_SRC);
+
+    public final static MatchField<EthType> ETH_TYPE =
+            new MatchField<EthType>("eth_type", MatchFields.ETH_TYPE);
+
+    public final static MatchField<VlanVid> VLAN_VID =
+            new MatchField<VlanVid>("vlan_vid", MatchFields.VLAN_VID);
+
+    public final static MatchField<VlanPcp> VLAN_PCP =
+            new MatchField<VlanPcp>("vlan_pcp", MatchFields.VLAN_PCP,
+                    new Prerequisite<VlanVid>(MatchField.VLAN_VID));
+
+    public final static MatchField<IpDscp> IP_DSCP =
+            new MatchField<IpDscp>("ip_dscp", MatchFields.IP_DSCP,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv4, EthType.ETH_TYPE_IPv6));
+
+    public final static MatchField<IpEcn> IP_ECN =
+            new MatchField<IpEcn>("ip_dscp", MatchFields.IP_ECN,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv4, EthType.ETH_TYPE_IPv6));
+
+    public final static MatchField<IpProtocol> IP_PROTO =
+            new MatchField<IpProtocol>("ip_proto", MatchFields.IP_PROTO,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv4, EthType.ETH_TYPE_IPv6));
+
+    public final static MatchField<IPv4> IPV4_SRC =
+            new MatchField<IPv4>("ipv4_src", MatchFields.IPV4_SRC,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv4));
+
+    public final static MatchField<IPv4> IPV4_DST =
+            new MatchField<IPv4>("ipv4_dst", MatchFields.IPV4_DST,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv4));
+
+    public final static MatchField<TransportPort> TCP_SRC = new MatchField<TransportPort>(
+            "tcp_src", MatchFields.TCP_SRC,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_TCP));
+
+    public final static MatchField<TransportPort> TCP_DST = new MatchField<TransportPort>(
+            "tcp_dst", MatchFields.TCP_DST,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_TCP));
+
+    public final static MatchField<TransportPort> UDP_SRC = new MatchField<TransportPort>(
+            "udp_src", MatchFields.UDP_SRC,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_UDP));
+
+    public final static MatchField<TransportPort> UDP_DST = new MatchField<TransportPort>(
+            "udp_dst", MatchFields.UDP_DST,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_UDP));
+
+    public final static MatchField<TransportPort> SCTP_SRC = new MatchField<TransportPort>(
+            "sctp_src", MatchFields.SCTP_SRC,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_SCTP));
+
+    public final static MatchField<TransportPort> SCTP_DST = new MatchField<TransportPort>(
+            "sctp_dst", MatchFields.SCTP_DST,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_SCTP));
+
+    public final static MatchField<ICMPv4Type> ICMPV4_TYPE = new MatchField<ICMPv4Type>(
+            "icmpv4_src", MatchFields.ICMPV4_TYPE,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_ICMP));
+
+    public final static MatchField<ICMPv4Code> ICMPV4_CODE = new MatchField<ICMPv4Code>(
+            "icmpv4_dst", MatchFields.ICMPV4_CODE,
+            new Prerequisite<IpProtocol>(MatchField.IP_PROTO, IpProtocol.IP_PROTO_ICMP));
+
+    public final static MatchField<ArpOpcode> ARP_OP = new MatchField<ArpOpcode>(
+            "arp_op", MatchFields.ARP_OP,
+            new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_ARP));
+
+    public final static MatchField<IPv4> ARP_SPA =
+            new MatchField<IPv4>("arp_spa", MatchFields.ARP_SPA,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_ARP));
+
+    public final static MatchField<IPv4> ARP_TPA =
+            new MatchField<IPv4>("arp_tpa", MatchFields.ARP_TPA,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_ARP));
+
+    public final static MatchField<MacAddress> ARP_SHA =
+            new MatchField<MacAddress>("arp_sha", MatchFields.ARP_SHA,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_ARP));
+
+    public final static MatchField<MacAddress> ARP_THA =
+            new MatchField<MacAddress>("arp_tha", MatchFields.ARP_THA,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_ARP));
+
+    public final static MatchField<IPv6> IPV6_SRC =
+            new MatchField<IPv6>("ipv6_src", MatchFields.IPV6_SRC,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv6));
+
+    public final static MatchField<IPv6> IPV6_DST =
+            new MatchField<IPv6>("ipv6_dst", MatchFields.IPV6_DST,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv6));
+
+    public final static MatchField<IPv6FlowLabel> IPV6_FLABEL =
+            new MatchField<IPv6FlowLabel>("ipv6_flabel", MatchFields.IPV6_FLABEL,
+                    new Prerequisite<EthType>(MatchField.ETH_TYPE, EthType.ETH_TYPE_IPv6));
+
+    public String getName() {
+        return name;
+    }
+
+    public boolean arePrerequisitesOK(Match match) {
+        for (Prerequisite<?> p : this.prerequisites) {
+            if (!p.isSatisfied(match)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+}
diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchFields.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchFields.java
new file mode 100644
index 0000000..2fc10ae
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/MatchFields.java
@@ -0,0 +1,34 @@
+package org.projectfloodlight.openflow.protocol.match;
+
+// MUST BE ORDERED BY THE ORDER OF OF SPEC!!!
+public enum MatchFields {
+    IN_PORT,
+    IN_PHY_PORT,
+    METADATA,
+    ETH_DST,
+    ETH_SRC,
+    ETH_TYPE,
+    VLAN_VID,
+    VLAN_PCP,
+    IP_DSCP,
+    IP_ECN,
+    IP_PROTO,
+    IPV4_SRC,
+    IPV4_DST,
+    TCP_SRC,
+    TCP_DST,
+    UDP_SRC,
+    UDP_DST,
+    SCTP_SRC,
+    SCTP_DST,
+    ICMPV4_TYPE,
+    ICMPV4_CODE,
+    ARP_OP,
+    ARP_SPA,
+    ARP_TPA,
+    ARP_SHA,
+    ARP_THA,
+    IPV6_SRC,
+    IPV6_DST,
+    IPV6_FLABEL,
+}
diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Prerequisite.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Prerequisite.java
new file mode 100644
index 0000000..4e667e7
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/protocol/match/Prerequisite.java
@@ -0,0 +1,44 @@
+package org.projectfloodlight.openflow.protocol.match;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.projectfloodlight.openflow.types.OFValueType;
+
+public class Prerequisite<T extends OFValueType<T>> {
+    private final MatchField<T> field;
+    private final Set<OFValueType<T>> values;
+    private boolean any;
+
+    public Prerequisite(MatchField<T> field, OFValueType<T>... values) {
+        this.values = new HashSet<OFValueType<T>>();
+        this.field = field;
+        if (values == null || values.length == 0) {
+            this.any = true;
+        } else {
+            this.any = false;
+            for (OFValueType<T> value : values) {
+                this.values.add(value);
+            }
+        }
+    }
+
+    /**
+     * Returns true if this prerequisite is satisfied by the given match object.
+     *
+     * @param match Match object
+     * @return true iff prerequisite is satisfied.
+     */
+    public boolean isSatisfied(Match match) {
+        OFValueType<T> res = match.get(this.field);
+        if (res == null)
+            return false;
+        if (this.any)
+            return true;
+        if (this.values.contains(res)) {
+            return true;
+        }
+        return false;
+    }
+
+}