package javax.jms;

import java.util.Enumeration;

/** A <CODE>MapMessage</CODE> object is used to send a set of name-value pairs.
 * The names are <CODE>String</CODE> objects, and the values are primitive 
 * data types in the Java programming language. The names must have a value that
 * is not null, and not an empty string. The entries can be accessed 
 * sequentially or randomly by name. The order of the entries is undefined. 
 * <CODE>MapMessage</CODE> inherits from the <CODE>Message</CODE> interface
 * and adds a message body that contains a Map.
 *
 * <P>The primitive types can be read or written explicitly using methods
 * for each type. They may also be read or written generically as objects.
 * For instance, a call to <CODE>MapMessage.setInt("foo", 6)</CODE> is 
 * equivalent to <CODE>MapMessage.setObject("foo", new Integer(6))</CODE>.
 * Both forms are provided, because the explicit form is convenient for
 * static programming, and the object form is needed when types are not known
 * at compile time.
 *
 * <P>When a client receives a <CODE>MapMessage</CODE>, it is in read-only 
 * mode. If a client attempts to write to the message at this point, a 
 * <CODE>MessageNotWriteableException</CODE> is thrown. If 
 * <CODE>clearBody</CODE> is called, the message can now be both read from and 
 * written to.
 *
 * <P><CODE>MapMessage</CODE> objects support the following conversion table. 
 * The marked cases must be supported. The unmarked cases must throw a 
 * <CODE>JMSException</CODE>. The <CODE>String</CODE>-to-primitive conversions 
 * may throw a runtime exception if the primitive's <CODE>valueOf()</CODE> 
 * method does not accept it as a valid <CODE>String</CODE> representation of 
 * the primitive.
 *
 * <P>A value written as the row type can be read as the column type.
 *
 * <PRE>
 * |        | boolean byte short char int long float double String byte[]
 * |----------------------------------------------------------------------
 * |boolean |    X                                            X
 * |byte    |          X     X         X   X                  X
 * |short   |                X         X   X                  X
 * |char    |                     X                           X
 * |int     |                          X   X                  X
 * |long    |                              X                  X
 * |float   |                                    X     X      X
 * |double  |                                          X      X
 * |String  |    X     X     X         X   X     X     X      X
 * |byte[]  |                                                        X
 * |----------------------------------------------------------------------
 * </PRE>
 *
 * <P>Attempting to read a null value as a primitive type must be treated
 * as calling the primitive's corresponding <code>valueOf(String)</code> 
 * conversion method with a null value. Since <code>char</code> does not 
 * support a <code>String</code> conversion, attempting to read a null value 
 * as a <code>char</code> must throw a <code>NullPointerException</code>.
 *
 * @see         javax.jms.Session#createMapMessage()
 * @see         javax.jms.BytesMessage
 * @see         javax.jms.Message
 * @see         javax.jms.ObjectMessage
 * @see         javax.jms.StreamMessage
 * @see         javax.jms.TextMessage
 */

public interface MapMessage extends Message
{

   /** Returns the <CODE>boolean</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>boolean</CODE>
    *
    * @return the <CODE>boolean</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   boolean getBoolean(String name) throws JMSException;

   /** Returns the <CODE>byte</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>byte</CODE>
    *
    * @return the <CODE>byte</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.
    */

   byte getByte(String name) throws JMSException;

   /** Returns the <CODE>short</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>short</CODE>
    *
    * @return the <CODE>short</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   short getShort(String name) throws JMSException;

   /** Returns the Unicode character value with the specified name.
    *
    * @param name the name of the Unicode character
    *
    * @return the Unicode character value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.     
    */

   char getChar(String name) throws JMSException;

   /** Returns the <CODE>int</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>int</CODE>
    *
    * @return the <CODE>int</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   int getInt(String name) throws JMSException;

   /** Returns the <CODE>long</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>long</CODE>
    *
    * @return the <CODE>long</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   long getLong(String name) throws JMSException;

   /** Returns the <CODE>float</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>float</CODE>
    *
    * @return the <CODE>float</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.     
    */

   float getFloat(String name) throws JMSException;

   /** Returns the <CODE>double</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>double</CODE>
    *
    * @return the <CODE>double</CODE> value with the specified name
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   double getDouble(String name) throws JMSException;

   /** Returns the <CODE>String</CODE> value with the specified name.
    *
    * @param name the name of the <CODE>String</CODE>
    *
    * @return the <CODE>String</CODE> value with the specified name; if there 
    * is no item by this name, a null value is returned
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   String getString(String name) throws JMSException;

   /** Returns the byte array value with the specified name.
    *
    * @param name the name of the byte array
    *
    * @return a copy of the byte array value with the specified name; if there
    * is no
    * item by this name, a null value is returned.
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    * @exception MessageFormatException if this type conversion is invalid.      
    */

   byte[] getBytes(String name) throws JMSException;

   /** Returns the value of the object with the specified name.
    *
    * <P>This method can be used to return, in objectified format,
    * an object in the Java programming language ("Java object") that had 
    * been stored in the Map with the equivalent
    * <CODE>setObject</CODE> method call, or its equivalent primitive
    * <CODE>set<I>type</I></CODE> method.
    *
    * <P>Note that byte values are returned as <CODE>byte[]</CODE>, not 
    * <CODE>Byte[]</CODE>.
    *
    * @param name the name of the Java object
    *
    * @return a copy of the Java object value with the specified name, in 
    * objectified format (for example, if the object was set as an 
    * <CODE>int</CODE>, an <CODE>Integer</CODE> is returned); if there is no 
    * item by this name, a null value is returned
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    */

   Object getObject(String name) throws JMSException;

   /** Returns an <CODE>Enumeration</CODE> of all the names in the 
    * <CODE>MapMessage</CODE> object.
    *
    * @return an enumeration of all the names in this <CODE>MapMessage</CODE>
    *
    * @exception JMSException if the JMS provider fails to read the message
    *                         due to some internal error.
    */

   Enumeration getMapNames() throws JMSException;

   /** Sets a <CODE>boolean</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>boolean</CODE>
    * @param value the <CODE>boolean</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setBoolean(String name, boolean value) throws JMSException;

   /** Sets a <CODE>byte</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>byte</CODE>
    * @param value the <CODE>byte</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setByte(String name, byte value) throws JMSException;

   /** Sets a <CODE>short</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>short</CODE>
    * @param value the <CODE>short</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setShort(String name, short value) throws JMSException;

   /** Sets a Unicode character value with the specified name into the Map.
    *
    * @param name the name of the Unicode character
    * @param value the Unicode character value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setChar(String name, char value) throws JMSException;

   /** Sets an <CODE>int</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>int</CODE>
    * @param value the <CODE>int</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setInt(String name, int value) throws JMSException;

   /** Sets a <CODE>long</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>long</CODE>
    * @param value the <CODE>long</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setLong(String name, long value) throws JMSException;

   /** Sets a <CODE>float</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>float</CODE>
    * @param value the <CODE>float</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setFloat(String name, float value) throws JMSException;

   /** Sets a <CODE>double</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>double</CODE>
    * @param value the <CODE>double</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setDouble(String name, double value) throws JMSException;

   /** Sets a <CODE>String</CODE> value with the specified name into the Map.
    *
    * @param name the name of the <CODE>String</CODE>
    * @param value the <CODE>String</CODE> value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setString(String name, String value) throws JMSException;

   /** Sets a byte array value with the specified name into the Map.
    *
    * @param name the name of the byte array
    * @param value the byte array value to set in the Map; the array
    *              is copied so that the value for <CODE>name</CODE> will
    *              not be altered by future modifications
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception NullPointerException if the name is null, or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setBytes(String name, byte[] value) throws JMSException;

   /** Sets a portion of the byte array value with the specified name into the 
    * Map.
    *  
    * @param name the name of the byte array
    * @param value the byte array value to set in the Map
    * @param offset the initial offset within the byte array
    * @param length the number of bytes to use
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setBytes(String name, byte[] value, int offset, int length) throws JMSException;

   /** Sets an object value with the specified name into the Map.
    *
    * <P>This method works only for the objectified primitive
    * object types (<code>Integer</code>, <code>Double</code>, 
    * <code>Long</code>&nbsp;...), <code>String</code> objects, and byte 
    * arrays.
    *
    * @param name the name of the Java object
    * @param value the Java object value to set in the Map
    *
    * @exception JMSException if the JMS provider fails to write the message
    *                         due to some internal error.
    * @exception IllegalArgumentException if the name is null or if the name is
    *                          an empty string.
    * @exception MessageFormatException if the object is invalid.
    * @exception MessageNotWriteableException if the message is in read-only 
    *                                         mode.
    */

   void setObject(String name, Object value) throws JMSException;

   /** Indicates whether an item exists in this <CODE>MapMessage</CODE> object.
    *
    * @param name the name of the item to test
    *
    * @return true if the item exists
    *
    * @exception JMSException if the JMS provider fails to determine if the 
    *                         item exists due to some internal error.
    */

   boolean itemExists(String name) throws JMSException;
}
