Module com.maxmind.db
Package com.maxmind.db

Class Reader

java.lang.Object
com.maxmind.db.Reader
All Implemented Interfaces:
Closeable, AutoCloseable
public final class Reader extends Object implements Closeable
Instances of this class provide a reader for the MaxMind DB format. IP addresses can be looked up using the get method.

  • Constructor Details

    • Reader

      public Reader(File database) throws IOException
      Constructs a Reader for the MaxMind DB format, with no caching. The file passed to it must be a valid MaxMind DB file such as a GeoIP2 database file.
      Parameters:
      database - the MaxMind DB file to use.
      Throws:
      IOException - if there is an error opening or reading from the file.

    • Reader

      public Reader(File database, NodeCache cache) throws IOException
      Constructs a Reader for the MaxMind DB format, with the specified backing cache. The file passed to it must be a valid MaxMind DB file such as a GeoIP2 database file.
      Parameters:
      database - the MaxMind DB file to use.
      cache - backing cache instance
      Throws:
      IOException - if there is an error opening or reading from the file.

    • Reader

      public Reader(InputStream source) throws IOException
      Constructs a Reader with no caching, as if in mode Reader.FileMode.MEMORY, without using a File instance.
      Parameters:
      source - the InputStream that contains the MaxMind DB file.
      Throws:
      IOException - if there is an error reading from the Stream.

    • Reader

      public Reader(InputStream source, NodeCache cache) throws IOException
      Constructs a Reader with the specified backing cache, as if in mode Reader.FileMode.MEMORY, without using a File instance.
      Parameters:
      source - the InputStream that contains the MaxMind DB file.
      cache - backing cache instance
      Throws:
      IOException - if there is an error reading from the Stream.

    • Reader

      public Reader(File database, Reader.FileMode fileMode) throws IOException
      Constructs a Reader for the MaxMind DB format, with no caching. The file passed to it must be a valid MaxMind DB file such as a GeoIP2 database file.
      Parameters:
      database - the MaxMind DB file to use.
      fileMode - the mode to open the file with.
      Throws:
      IOException - if there is an error opening or reading from the file.

    • Reader

      public Reader(File database, Reader.FileMode fileMode, NodeCache cache) throws IOException
      Constructs a Reader for the MaxMind DB format, with the specified backing cache. The file passed to it must be a valid MaxMind DB file such as a GeoIP2 database file.
      Parameters:
      database - the MaxMind DB file to use.
      fileMode - the mode to open the file with.
      cache - backing cache instance
      Throws:
      IOException - if there is an error opening or reading from the file.

  • Method Details

    • get

      public <T> T get(InetAddress ipAddress, Class<T> cls) throws IOException
      Looks up ipAddress in the MaxMind DB.
      Type Parameters:
      T - the type to populate.
      Parameters:
      ipAddress - the IP address to look up.
      cls - the class of object to populate.
      Returns:
      the object.
      Throws:
      IOException - if a file I/O error occurs.

    • getRecord

      public <T> DatabaseRecord<T> getRecord(InetAddress ipAddress, Class<T> cls) throws IOException
      Looks up ipAddress in the MaxMind DB.
      Type Parameters:
      T - the type to populate.
      Parameters:
      ipAddress - the IP address to look up.
      cls - the class of object to populate.
      Returns:
      the record for the IP address. If there is no data for the address, the non-null DatabaseRecord will still be returned.
      Throws:
      IOException - if a file I/O error occurs.

    • networks

      public <T> Networks<T> networks(Class<T> typeParameterClass) throws InvalidNetworkException, ClosedDatabaseException, InvalidDatabaseException
      Creates a Networks iterator and skips aliased networks. Please note that a MaxMind DB may map IPv4 networks into several locations in an IPv6 database. networks() iterates over the canonical locations and not the aliases. To include the aliases, you can set includeAliasedNetworks to true.
      Type Parameters:
      T - Represents the data type(e.g., Map, HastMap, etc.).
      Parameters:
      typeParameterClass - The type of data returned by the iterator.
      Returns:
      Networks The Networks iterator.
      Throws:
      InvalidNetworkException - Exception for using an IPv6 network in ipv4-only database.
      ClosedDatabaseException - Exception for a closed databased.
      InvalidDatabaseException - Exception for an invalid database.

    • networks

      public <T> Networks<T> networks(boolean includeAliasedNetworks, Class<T> typeParameterClass) throws InvalidNetworkException, ClosedDatabaseException, InvalidDatabaseException
      Creates a Networks iterator. Please note that a MaxMind DB may map IPv4 networks into several locations in an IPv6 database. This iterator will iterate over all of these locations separately. To set the iteration over the IPv4 networks once, use the includeAliasedNetworks option.
      Type Parameters:
      T - Represents the data type(e.g., Map, HastMap, etc.).
      Parameters:
      includeAliasedNetworks - Enable including aliased networks.
      Returns:
      Networks The Networks iterator.
      Throws:
      InvalidNetworkException - Exception for using an IPv6 network in ipv4-only database.
      ClosedDatabaseException - Exception for a closed databased.
      InvalidDatabaseException - Exception for an invalid database.

    • networksWithin

      public <T> Networks<T> networksWithin(Network network, boolean includeAliasedNetworks, Class<T> typeParameterClass) throws InvalidNetworkException, ClosedDatabaseException, InvalidDatabaseException
      Returns an iterator within the specified network. Please note that a MaxMind DB may map IPv4 networks into several locations in an IPv6 database. This iterator will iterate over all of these locations separately. To only iterate over the IPv4 networks once, use the includeAliasedNetworks option.
      Type Parameters:
      T - Represents the data type(e.g., Map, HastMap, etc.).
      Parameters:
      network - Specifies the network to be iterated.
      includeAliasedNetworks - Boolean for including aliased networks.
      typeParameterClass - The type of data returned by the iterator.
      Returns:
      Networks
      Throws:
      InvalidNetworkException - Exception for using an IPv6 network in ipv4-only database.
      ClosedDatabaseException - Exception for a closed databased.
      InvalidDatabaseException - Exception for an invalid database.

    • getMetadata

      public Metadata getMetadata()
      Returns:
      the metadata for the MaxMind DB file.

    • close

      public void close() throws IOException

      Closes the database.

      If you are using FileMode.MEMORY_MAPPED, this will not unmap the underlying file due to a limitation in Java's MappedByteBuffer. It will however set the reference to the buffer to null, allowing the garbage collector to collect it.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException - if an I/O error occurs.