diff --git a/router/java/src/com/maxmind/geoip2/DatabaseReader.java b/router/java/src/com/maxmind/geoip2/DatabaseReader.java
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+package com.maxmind.geoip2;
+
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.maxmind.db.*;
+import com.maxmind.db.Reader.FileMode;
+import com.maxmind.geoip2.exception.AddressNotFoundException;
+import com.maxmind.geoip2.exception.GeoIp2Exception;
+import com.maxmind.geoip2.model.*;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.InetAddress;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * <p>
+ * The class {@code DatabaseReader} provides a reader for the GeoIP2 database
+ * format.
+ * </p>
+ * <h3>Usage</h3>
+ * <p>
+ * To use the database API, you must create a new {@code DatabaseReader} using
+ * the {@code DatabaseReader.Builder}. You must provide the {@code Builder}
+ * constructor either an {@code InputStream} or {@code File} for your GeoIP2
+ * database. You may also specify the {@code fileMode} and the {@code locales}
+ * fallback order using the methods on the {@code Builder} object. After you
+ * have created the {@code DatabaseReader}, you may then call the appropriate
+ * method (e.g., {@code city}) for your database, passing it the IP address
+ * you want to look up.
+ * </p>
+ * <p>
+ * If the lookup succeeds, the method call will return a response class for
+ * the GeoIP2 lookup. The class in turn contains multiple record classes,
+ * each of which represents part of the data returned by the database.
+ * </p>
+ * <p>
+ * We recommend reusing the {@code DatabaseReader} object rather than creating
+ * a new one for each lookup. The creation of this object is relatively
+ * expensive as it must read in metadata for the file. It is safe to share the
+ * object across threads.
+ * </p>
+ * <h4>Caching</h4>
+ * <p>
+ * The database API supports pluggable caching (by default, no caching is
+ * performed). A simple implementation is provided by
+ * {@code com.maxmind.db.CHMCache}. Using this cache, lookup performance is
+ * significantly improved at the cost of a small (~2MB) memory overhead.
+ * </p>
+ */
+public class DatabaseReader implements DatabaseProvider, Closeable {
+
+ private final Reader reader;
+
+ private final ObjectMapper om;
+
+ private final List<String> locales;
+
+ private DatabaseReader(Builder builder) throws IOException {
+ if (builder.stream != null) {
+ this.reader = new Reader(builder.stream, builder.cache);
+ } else if (builder.database != null) {
+ this.reader = new Reader(builder.database, builder.mode, builder.cache);
+ } else {
+ // This should never happen. If it does, review the Builder class
+ // constructors for errors.
+ throw new IllegalArgumentException(
+ "Unsupported Builder configuration: expected either File or URL");
+ }
+ this.om = new ObjectMapper();
+ this.om.configure(MapperFeature.CAN_OVERRIDE_ACCESS_MODIFIERS, false);
+ this.om.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES,
+ false);
+ this.om.configure(
+ DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL, true);
+ this.locales = builder.locales;
+ }
+
+ /**
+ * <p>
+ * Constructs a Builder for the {@code DatabaseReader}. The file passed to
+ * it must be a valid GeoIP2 database file.
+ * </p>
+ * <p>
+ * {@code Builder} creates instances of {@code DatabaseReader}
+ * from values set by the methods.
+ * </p>
+ * <p>
+ * Only the values set in the {@code Builder} constructor are required.
+ * </p>
+ */
+ public static final class Builder {
+ final File database;
+ final InputStream stream;
+
+ List<String> locales = Collections.singletonList("en");
+ FileMode mode = FileMode.MEMORY_MAPPED;
+ NodeCache cache = NoCache.getInstance();
+
+ /**
+ * @param stream the stream containing the GeoIP2 database to use.
+ */
+ public Builder(InputStream stream) {
+ this.stream = stream;
+ this.database = null;
+ }
+
+ /**
+ * @param database the GeoIP2 database file to use.
+ */
+ public Builder(File database) {
+ this.database = database;
+ this.stream = null;
+ }
+
+ /**
+ * @param val List of locale codes to use in name property from most
+ * preferred to least preferred.
+ * @return Builder object
+ */
+ public Builder locales(List<String> val) {
+ this.locales = val;
+ return this;
+ }
+
+ /**
+ * @param cache backing cache instance
+ * @return Builder object
+ */
+ public Builder withCache(NodeCache cache) {
+ this.cache = cache;
+ return this;
+ }
+
+ /**
+ * @param val The file mode used to open the GeoIP2 database
+ * @return Builder object
+ * @throws java.lang.IllegalArgumentException if you initialized the Builder with a URL, which uses
+ * {@link FileMode#MEMORY}, but you provided a different
+ * FileMode to this method.
+ */
+ public Builder fileMode(FileMode val) {
+ if (this.stream != null && FileMode.MEMORY != val) {
+ throw new IllegalArgumentException(
+ "Only FileMode.MEMORY is supported when using an InputStream.");
+ }
+ this.mode = val;
+ return this;
+ }
+
+ /**
+ * @return an instance of {@code DatabaseReader} created from the
+ * fields set on this builder.
+ * @throws IOException if there is an error reading the database
+ */
+ public DatabaseReader build() throws IOException {
+ return new DatabaseReader(this);
+ }
+ }
+
+ /**
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return A <T> object with the data for the IP address
+ * @throws IOException if there is an error opening or reading from the file.
+ * @throws AddressNotFoundException if the IP address is not in our database
+ */
+ private <T> T get(InetAddress ipAddress, Class<T> cls,
+ String type) throws IOException, AddressNotFoundException {
+
+ String databaseType = this.getMetadata().getDatabaseType();
+ if (!databaseType.contains(type)) {
+ String caller = Thread.currentThread().getStackTrace()[2]
+ .getMethodName();
+ throw new UnsupportedOperationException(
+ "Invalid attempt to open a " + databaseType
+ + " database using the " + caller + " method");
+ }
+
+ ObjectNode node = jsonNodeToObjectNode(reader.get(ipAddress));
+
+ // We throw the same exception as the web service when an IP is not in
+ // the database
+ if (node == null) {
+ throw new AddressNotFoundException("The address "
+ + ipAddress.getHostAddress() + " is not in the database.");
+ }
+
+ InjectableValues inject = new JsonInjector(locales, ipAddress.getHostAddress());
+
+ return this.om.reader(inject).treeToValue(node, cls);
+ }
+
+ private ObjectNode jsonNodeToObjectNode(JsonNode node)
+ throws InvalidDatabaseException {
+ if (node == null || node instanceof ObjectNode) {
+ return (ObjectNode) node;
+ }
+ throw new InvalidDatabaseException(
+ "Unexpected data type returned. The GeoIP2 database may be corrupt.");
+ }
+
+ /**
+ * <p>
+ * Closes the database.
+ * </p>
+ * <p>
+ * If you are using {@code FileMode.MEMORY_MAPPED}, this will
+ * <em>not</em> unmap the underlying file due to a limitation in Java's
+ * {@code MappedByteBuffer}. It will however set the reference to
+ * the buffer to {@code null}, allowing the garbage collector to
+ * collect it.
+ * </p>
+ *
+ * @throws IOException if an I/O error occurs.
+ */
+ @Override
+ public void close() throws IOException {
+ this.reader.close();
+ }
+
+ @Override
+ public CountryResponse country(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, CountryResponse.class, "Country");
+ }
+
+ @Override
+ public CityResponse city(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, CityResponse.class, "City");
+ }
+
+ /**
+ * Look up an IP address in a GeoIP2 Anonymous IP.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return a AnonymousIpResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public AnonymousIpResponse anonymousIp(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, AnonymousIpResponse.class, "GeoIP2-Anonymous-IP");
+ }
+
+ /**
+ * Look up an IP address in a GeoLite2 ASN database.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return an AsnResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public AsnResponse asn(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, AsnResponse.class, "GeoLite2-ASN");
+ }
+
+ /**
+ * Look up an IP address in a GeoIP2 Connection Type database.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return a ConnectTypeResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public ConnectionTypeResponse connectionType(InetAddress ipAddress)
+ throws IOException, GeoIp2Exception {
+ return this.get(ipAddress, ConnectionTypeResponse.class,
+ "GeoIP2-Connection-Type");
+ }
+
+ /**
+ * Look up an IP address in a GeoIP2 Domain database.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return a DomainResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public DomainResponse domain(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this
+ .get(ipAddress, DomainResponse.class, "GeoIP2-Domain");
+ }
+
+ /**
+ * Look up an IP address in a GeoIP2 Enterprise database.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return an EnterpriseResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public EnterpriseResponse enterprise(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, EnterpriseResponse.class, "Enterprise");
+ }
+
+
+ /**
+ * Look up an IP address in a GeoIP2 ISP database.
+ *
+ * @param ipAddress IPv4 or IPv6 address to lookup.
+ * @return an IspResponse for the requested IP address.
+ * @throws GeoIp2Exception if there is an error looking up the IP
+ * @throws IOException if there is an IO error
+ */
+ @Override
+ public IspResponse isp(InetAddress ipAddress) throws IOException,
+ GeoIp2Exception {
+ return this.get(ipAddress, IspResponse.class, "GeoIP2-ISP");
+ }
+
+ /**
+ * @return the metadata for the open MaxMind DB file.
+ */
+ public Metadata getMetadata() {
+ return this.reader.getMetadata();
+ }
+}