Class RabbitMQUtils


  • public class RabbitMQUtils
    extends Object
    Contains utility methods for working with RabbitMQ.
    Author:
    Michael Röder (roeder@informatik.uni-leipzig.de)
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static org.apache.jena.riot.Lang DEFAULT_RDF_LANG  
      private static org.slf4j.Logger LOGGER  
    • Constructor Summary

      Constructors 
      Constructor Description
      RabbitMQUtils()  
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static byte[] readByteArray​(ByteBuffer buffer)
      Reads a byte array from the given buffer assuming that it is preceded by an int value containing the length of the byte array.
      static long readLong​(byte[] data)
      Reads a long value from the given byte array.
      static long readLong​(byte[] data, int offset, int length)
      Reads a long value from the given byte array.
      static org.apache.jena.rdf.model.Model readModel​(byte[] data)
      Reads an RDF model from the given byte array.
      static org.apache.jena.rdf.model.Model readModel​(byte[] data, int offset, int length)
      Reads an RDF model from the given byte array.
      static org.apache.jena.rdf.model.Model readModel​(String string)
      Reads an RDF model from the given String.
      static org.apache.jena.rdf.model.Model readModel​(ByteBuffer buffer)
      Reads an RDF model from the given byte buffer assuming that the byte array containing the model is preceded by an int containing its length.
      static String readString​(byte[] data)
      Transforms the given byte data into a String using the UTF-8 encoding.
      static String readString​(byte[] data, int offset, int length)
      Transforms the given byte data into a String using the UTF-8 encoding.
      static String readString​(ByteBuffer buffer)
      Reads a String from the given buffer assuming that it is preceded by an int value containing the length of the String.
      static byte[] writeByteArrays​(byte[][] arrays)
      writes the given byte arrays and puts their length in front of them.
      static byte[] writeByteArrays​(byte[] precedingData, byte[][] arrays, byte[] subsequentData)
      writes the given byte arrays and puts their length in front of them.
      static byte[] writeLong​(long value)
      Creates a byte array representing the given long value.
      static byte[] writeModel​(org.apache.jena.rdf.model.Model model)
      Creates a byte array containing the serialized RDF model using the DEFAULT_RDF_LANG.
      static String writeModel2String​(org.apache.jena.rdf.model.Model model)
      Creates a String containing the serialized RDF model using the DEFAULT_RDF_LANG.
      static byte[] writeString​(String string)
      Creates a byte array representation of the given String using UTF-8 encoding.
    • Field Detail

      • LOGGER

        private static final org.slf4j.Logger LOGGER
      • DEFAULT_RDF_LANG

        public static final org.apache.jena.riot.Lang DEFAULT_RDF_LANG
    • Constructor Detail

      • RabbitMQUtils

        public RabbitMQUtils()
    • Method Detail

      • readByteArray

        public static byte[] readByteArray​(ByteBuffer buffer)
        Reads a byte array from the given buffer assuming that it is preceded by an int value containing the length of the byte array.
        Parameters:
        buffer - the buffer containing an int containing the length of the byte array followed by the byte array itself
        Returns:
        the byte array or null if the given byte array is null
      • readModel

        public static org.apache.jena.rdf.model.Model readModel​(byte[] data)
        Reads an RDF model from the given byte array.
        Parameters:
        data - the byte array containing the serialized RDF model
        Returns:
        the deserialized model
      • readModel

        public static org.apache.jena.rdf.model.Model readModel​(byte[] data,
                                                                int offset,
                                                                int length)
        Reads an RDF model from the given byte array.
        Parameters:
        data - the byte array containing the serialized RDF model
        offset - position at which the parsing will start
        length - number of bytes that should be parsed
        Returns:
        the deserialized model
      • readModel

        public static org.apache.jena.rdf.model.Model readModel​(String string)
        Reads an RDF model from the given String.
        Parameters:
        string - the String containing the serialized RDF model
        Returns:
        the deserialized model
      • readModel

        public static org.apache.jena.rdf.model.Model readModel​(ByteBuffer buffer)
        Reads an RDF model from the given byte buffer assuming that the byte array containing the model is preceded by an int containing its length.
        Parameters:
        buffer - the buffer containing the length of the serialized model (as int) and the byte array containing the serialized model
        Returns:
        the deserialized model
      • readString

        public static String readString​(byte[] data)
        Transforms the given byte data into a String using the UTF-8 encoding.
        Parameters:
        data - the byte array that should be transformed
        Returns:
        the String or null if the given byte array is null
      • readString

        public static String readString​(byte[] data,
                                        int offset,
                                        int length)
        Transforms the given byte data into a String using the UTF-8 encoding.
        Parameters:
        data - the byte array that should be transformed
        offset - position at which the parsing will start
        length - number of bytes that should be parsed
        Returns:
        the String or null if the given byte array is null
      • readString

        public static String readString​(ByteBuffer buffer)
        Reads a String from the given buffer assuming that it is preceded by an int value containing the length of the String.
        Parameters:
        buffer - the buffer that contains the byte data of the String
        Returns:
        the String or null if the given buffer is null
      • writeByteArrays

        public static byte[] writeByteArrays​(byte[][] arrays)
        writes the given byte arrays and puts their length in front of them. Thus, they can be read using a ByteBuffer and the readByteArray(ByteBuffer) method.
        Parameters:
        arrays - arrays that should be written to a single array
        Returns:
        the byte array containing all given arrays and their lengths
      • writeByteArrays

        public static byte[] writeByteArrays​(byte[] precedingData,
                                             byte[][] arrays,
                                             byte[] subsequentData)
        writes the given byte arrays and puts their length in front of them. Thus, they can be read using a ByteBuffer and the readByteArray(ByteBuffer) method.
        Parameters:
        precedingData - data that should be written before the arrays are written. Note that this data is not preceded with the byte array length.
        arrays - arrays that should be written to a single array
        subsequentData - data that should be written after the arrays are written. Note that this data is not preceded with the byte array length.
        Returns:
        the byte array containing all given arrays and their lengths
      • writeString

        public static byte[] writeString​(String string)
        Creates a byte array representation of the given String using UTF-8 encoding.
        Parameters:
        string - the String that should be transformed into a byte array
        Returns:
        the UTF-8 byte array of the given String
      • writeModel2String

        public static String writeModel2String​(org.apache.jena.rdf.model.Model model)
        Creates a String containing the serialized RDF model using the DEFAULT_RDF_LANG.
        Parameters:
        model - the model that should be serialized
        Returns:
        the String containing the model
      • writeModel

        public static byte[] writeModel​(org.apache.jena.rdf.model.Model model)
        Creates a byte array containing the serialized RDF model using the DEFAULT_RDF_LANG.
        Parameters:
        model - the model that should be serialized
        Returns:
        the byte array containing the model
      • writeLong

        public static byte[] writeLong​(long value)
        Creates a byte array representing the given long value.
        Parameters:
        value - the value that should be serialized
        Returns:
        the byte array containing the given long value
      • readLong

        public static long readLong​(byte[] data)
        Reads a long value from the given byte array.
        Parameters:
        data - a serialized long value
        Returns:
        the value read from the array
      • readLong

        public static long readLong​(byte[] data,
                                    int offset,
                                    int length)
        Reads a long value from the given byte array.
        Parameters:
        data - a serialized long value
        offset - position at which the parsing will start
        length - number of bytes that should be parsed (should equal Long.BYTES)
        Returns:
        the value read from the array