Document and clean up UUID factory API and implementation.

[lgpl/argeo-commons.git] / org.argeo.cms / src / org / argeo / cms / acr / CmsUuidFactory.java

diff --git a/org.argeo.cms/src/org/argeo/cms/acr/CmsUuidFactory.java b/org.argeo.cms/src/org/argeo/cms/acr/CmsUuidFactory.java
new file mode 100644 (file)
index 0000000..de0be36
--- /dev/null
+++ b/org.argeo.cms/src/org/argeo/cms/acr/CmsUuidFactory.java
@@ -0,0 +1,86 @@
+package org.argeo.cms.acr;
+
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.InterfaceAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.util.BitSet;
+import java.util.Enumeration;
+
+import org.argeo.api.cms.CmsLog;
+import org.argeo.api.uuid.ConcurrentUuidFactory;
+import org.argeo.api.uuid.UuidBinaryUtils;
+
+public class CmsUuidFactory extends ConcurrentUuidFactory {
+       private final static CmsLog log = CmsLog.getLog(CmsUuidFactory.class);
+
+       public CmsUuidFactory(byte[] nodeId) {
+               super(nodeId);
+               assert newTimeUUID().node() == BitSet.valueOf(toNodeIdBytes(nodeId, 0)).toLongArray()[0];
+       }
+
+       public CmsUuidFactory() {
+               this(getIpBytes());
+       }
+
+       /** Returns an SHA1 digest of one of the IP addresses. */
+       protected static byte[] getIpBytes() {
+               Enumeration<NetworkInterface> netInterfaces = null;
+               try {
+                       netInterfaces = NetworkInterface.getNetworkInterfaces();
+               } catch (SocketException e) {
+                       throw new IllegalStateException(e);
+               }
+               if (netInterfaces == null)
+                       throw new IllegalStateException("No interfaces");
+
+               InetAddress selectedIpv6 = null;
+               InetAddress selectedIpv4 = null;
+               netInterfaces: while (netInterfaces.hasMoreElements()) {
+                       NetworkInterface netInterface = netInterfaces.nextElement();
+                       byte[] hardwareAddress = null;
+                       try {
+                               hardwareAddress = netInterface.getHardwareAddress();
+                               if (hardwareAddress != null) {
+                                       // first IPv6
+                                       addr: for (InterfaceAddress addr : netInterface.getInterfaceAddresses()) {
+                                               InetAddress ip = addr.getAddress();
+                                               if (ip instanceof Inet6Address) {
+                                                       Inet6Address ipv6 = (Inet6Address) ip;
+                                                       if (ipv6.isAnyLocalAddress() || ipv6.isLinkLocalAddress() || ipv6.isLoopbackAddress())
+                                                               continue addr;
+                                                       selectedIpv6 = ipv6;
+                                                       break netInterfaces;
+                                               }
+
+                                       }
+                                       // then IPv4
+                                       addr: for (InterfaceAddress addr : netInterface.getInterfaceAddresses()) {
+                                               InetAddress ip = addr.getAddress();
+                                               if (ip instanceof Inet4Address) {
+                                                       Inet4Address ipv4 = (Inet4Address) ip;
+                                                       if (ipv4.isAnyLocalAddress() || ipv4.isLinkLocalAddress() || ipv4.isLoopbackAddress())
+                                                               continue addr;
+                                                       selectedIpv4 = ipv4;
+                                               }
+
+                                       }
+                               }
+                       } catch (SocketException e) {
+                               throw new IllegalStateException(e);
+                       }
+               }
+               InetAddress selectedIp = selectedIpv6 != null ? selectedIpv6 : selectedIpv4;
+               if (selectedIp == null)
+                       throw new IllegalStateException("No IP address found");
+               byte[] digest = sha1(selectedIp.getAddress());
+               log.info("Use IP " + selectedIp + " hashed as " + UuidBinaryUtils.toHexString(digest) + " as node id");
+               byte[] nodeId = toNodeIdBytes(digest, 0);
+               // marks that this is not based on MAC address
+               forceToNoMacAddress(nodeId, 0);
+               return nodeId;
+       }
+
+}