+import org.onap.aaf.cadi.LocatorException;
+
+public class DNSLocator implements SizedLocator<URI> {
+ private static enum Status {UNTRIED, OK, INVALID, SLOW};
+ private static final int CHECK_TIME = 3000;
+
+ private String host, protocol;
+ private Access access;
+ private Host[] hosts;
+ private int startPort, endPort;
+ private String suffix;
+
+ private int size = 1; // initial, until refreshed.
+
+ public DNSLocator(Access access, String protocol, String host, String range) {
+ this.host = host;
+ this.protocol = protocol;
+ this.access = access;
+ int dash = range.indexOf('-');
+ if (dash<0) {
+ startPort = endPort = Integer.parseInt(range);
+ } else {
+ startPort = Integer.parseInt(range.substring(0,dash));
+ endPort = Integer.parseInt(range.substring(dash + 1));
+ }
+ refresh();
+ }
+
+ public DNSLocator(Access access, String aaf_locate) throws LocatorException {
+ this.access = access;
+ if (aaf_locate==null) {
+ throw new LocatorException("Null passed into DNSLocator constructor");
+ }
+ int start, defPort;
+ if (aaf_locate.startsWith("https://")) {
+ protocol = "https";
+ start = 8; // https://
+ defPort = 443;
+ } else if (aaf_locate.startsWith("http://")) {
+ protocol = "http";
+ start = 7; // http://
+ defPort = 80;
+ } else {
+ throw new LocatorException("DNSLocator accepts only https or http protocols. (requested URL " + aaf_locate + ')');
+ }
+ host = parseHostAndPorts(aaf_locate, start, defPort);
+ refresh();
+ }
+
+ public static DNSLocator create(Access access, String url) throws LocatorException {
+ return new DNSLocator(access, url);
+ }
+
+ @Override
+ public URI get(Item item) throws LocatorException {
+ return hosts[((DLItem)item).cnt].uri;
+ }
+
+ @Override
+ public boolean hasItems() {
+ for (Host h : hosts) {
+ if (h.status==Status.OK) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ @Override
+ public void invalidate(Item item) {
+ DLItem di = (DLItem)item;
+ hosts[di.cnt].status = Status.INVALID;
+ }
+
+ @Override
+ public Item best() throws LocatorException {
+ // not a good "best"
+ for (int i=0;i<hosts.length;++i) {
+ switch(hosts[i].status) {
+ case OK:
+ return new DLItem(i);
+ case INVALID:
+ break;
+ case SLOW:
+ break;
+ case UNTRIED:
+ try {
+ if (hosts[i].ia.isReachable(CHECK_TIME)) {
+ hosts[i].status = Status.OK;
+ return new DLItem(i);
+ }
+ } catch (IOException e) {
+ throw new LocatorException(e);
+ }
+ break;
+ default:
+ break;
+ }
+ }
+ throw new LocatorException("No Available URIs for " + host);
+ }
+
+ @Override
+ public Item first() throws LocatorException {
+ return new DLItem(0);
+ }
+
+ @Override
+ public Item next(Item item) throws LocatorException {
+ DLItem di = (DLItem)item;
+ if (++di.cnt<hosts.length) {
+ return di;
+ } else {
+ return null;
+ }
+ }
+
+ @Override
+ public boolean refresh() {
+ try {
+ InetAddress[] ias = InetAddress.getAllByName(host);
+ Host[] temp = new Host[ias.length * (1 + endPort - startPort)];
+ int cnt = -1;
+ for (int j=startPort; j<=endPort; ++j) {
+ for (int i=0;i<ias.length;++i) {
+ temp[++cnt] = new Host(ias[i], j, suffix);
+ }
+ }
+ hosts = temp;
+ size = temp.length * (endPort-startPort+1);
+ return true;
+ } catch (Exception e) {
+ access.log(Level.ERROR, e);
+ }
+ return false;
+ }
+
+ private String parseHostAndPorts(String aaf_locate, int _start, int defaultPort) throws LocatorException {
+ int slash, start;
+ int colon = aaf_locate.indexOf(':',_start);
+ if (colon > 0) {
+ host = aaf_locate.substring(_start,colon);
+ start = colon + 1;
+ int left = aaf_locate.indexOf('[', start);
+ if (left > 0) {
+ int right = aaf_locate.indexOf(']', left + 1);
+ if (right < 0) {
+ throw new LocatorException("Missing closing bracket in DNSLocator constructor. (requested URL " + aaf_locate + ')');
+ } else if (right == (left + 1)) {
+ throw new LocatorException("Missing ports in brackets in DNSLocator constructor. (requested URL " + aaf_locate + ')');
+ }
+ int dash = aaf_locate.indexOf('-', left + 1);
+ if (dash == (right - 1) || dash == (left + 1)) {
+ throw new LocatorException("Missing ports in brackets in DNSLocator constructor. (requested URL " + aaf_locate + ')');
+ }
+ if (dash < 0) {
+ startPort = endPort = Integer.parseInt(aaf_locate.substring(left + 1, right));
+ } else {
+ startPort = Integer.parseInt(aaf_locate.substring(left + 1, dash));
+ endPort = Integer.parseInt(aaf_locate.substring(dash + 1, right));
+ }
+ slash = aaf_locate.indexOf('/', start);
+ if(slash>=0) {
+ suffix = aaf_locate.substring(slash);
+ }
+
+ } else {
+ slash = aaf_locate.indexOf('/', start);
+ if (slash == start) {
+ throw new LocatorException("Missing port before '/' in DNSLocator constructor. (requested URL " + aaf_locate + ')');
+ }
+ if (slash < 0) {
+ startPort = endPort = Integer.parseInt(aaf_locate.substring(start));
+ } else {
+ startPort = endPort = Integer.parseInt(aaf_locate.substring(start, slash));
+ suffix = aaf_locate.substring(slash);
+ }
+ }
+ } else {
+ slash = aaf_locate.indexOf('/', _start);
+ host = slash<_start?aaf_locate.substring(_start):aaf_locate.substring(_start,slash);
+ startPort = endPort = defaultPort;
+ }
+
+ return host;
+ }
+
+ private class Host {
+ private URI uri;
+ private InetAddress ia;
+ private Status status;
+
+ public Host(InetAddress inetAddress, int port, String suffix) throws URISyntaxException {
+ ia = inetAddress;
+ uri = new URI(protocol,null,inetAddress.getCanonicalHostName(),port,suffix,null,null);
+ status = Status.UNTRIED;
+ }
+
+ public String toString() {
+ return uri.toString() + " - " + status.name();
+ }
+ }
+
+ private class DLItem implements Item {
+ public DLItem(int i) {
+ cnt = i;
+ }
+
+ private int cnt;
+ }
+
+ public void destroy() {}