maputils.java

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     * <p>
     * If the value returned from the specified map is not a Map then
     * <code>null</code> is returned.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as a Map, <code>null</code> if null map input
     */
    public static Map getMap(final Map map, final Object key) {
        if (map != null) {
            Object answer = map.get(key);
            if (answer != null && answer instanceof Map) {
                return (Map) answer;
            }
        }
        return null;
    }

    // Type safe getters with default values
    //-------------------------------------------------------------------------
    /**
     *  Looks up the given key in the given map, converting null into the
     *  given default value.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null
     *  @return  the value in the map, or defaultValue if the original value
     *    is null or the map is null
     */
    public static Object getObject( Map map, Object key, Object defaultValue ) {
        if ( map != null ) {
            Object answer = map.get( key );
            if ( answer != null ) {
                return answer;
            }
        }
        return defaultValue;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a string, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a string, or defaultValue if the 
     *    original value is null, the map is null or the string conversion
     *    fails
     */
    public static String getString( Map map, Object key, String defaultValue ) {
        String answer = getString( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a boolean, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a boolean, or defaultValue if the 
     *    original value is null, the map is null or the boolean conversion
     *    fails
     */
    public static Boolean getBoolean( Map map, Object key, Boolean defaultValue ) {
        Boolean answer = getBoolean( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a number, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Number getNumber( Map map, Object key, Number defaultValue ) {
        Number answer = getNumber( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a byte, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Byte getByte( Map map, Object key, Byte defaultValue ) {
        Byte answer = getByte( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a short, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Short getShort( Map map, Object key, Short defaultValue ) {
        Short answer = getShort( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  an integer, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Integer getInteger( Map map, Object key, Integer defaultValue ) {
        Integer answer = getInteger( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a long, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Long getLong( Map map, Object key, Long defaultValue ) {
        Long answer = getLong( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a float, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Float getFloat( Map map, Object key, Float defaultValue ) {
        Float answer = getFloat( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a double, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the number conversion
     *    fails
     */
    public static Double getDouble( Map map, Object key, Double defaultValue ) {
        Double answer = getDouble( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }

    /**
     *  Looks up the given key in the given map, converting the result into
     *  a map, using the default value if the the conversion fails.
     *
     *  @param map  the map whose value to look up
     *  @param key  the key of the value to look up in that map
     *  @param defaultValue  what to return if the value is null or if the
     *     conversion fails
     *  @return  the value in the map as a number, or defaultValue if the 
     *    original value is null, the map is null or the map conversion
     *    fails
     */
    public static Map getMap( Map map, Object key, Map defaultValue ) {
        Map answer = getMap( map, key );
        if ( answer == null ) {
            answer = defaultValue;
        }
        return answer;
    }
    

    // Type safe primitive getters
    //-------------------------------------------------------------------------
    /**
     * Gets a boolean from a Map in a null-safe manner.
     * <p>
     * If the value is a <code>Boolean</code> its value is returned.
     * If the value is a <code>String</code> and it equals 'true' ignoring case
     * then <code>true</code> is returned, otherwise <code>false</code>.
     * If the value is a <code>Number</code> an integer zero value returns
     * <code>false</code> and non-zero returns <code>true</code>.
     * Otherwise, <code>false</code> is returned.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as a Boolean, <code>false</code> if null map input
     */
    public static boolean getBooleanValue(final Map map, final Object key) {
        Boolean booleanObject = getBoolean(map, key);
        if (booleanObject == null) {
            return false;
        }
        return booleanObject.booleanValue();
    }

    /**
     * Gets a byte from a Map in a null-safe manner.
     * <p>
     * The byte is obtained from the results of {@link #getNumber(Map,Object)}.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as a byte, <code>0</code> if null map input
     */
    public static byte getByteValue(final Map map, final Object key) {
        Byte byteObject = getByte(map, key);
        if (byteObject == null) {
            return 0;
        }
        return byteObject.byteValue();
    }

    /**
     * Gets a short from a Map in a null-safe manner.
     * <p>
     * The short is obtained from the results of {@link #getNumber(Map,Object)}.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as a short, <code>0</code> if null map input
     */
    public static short getShortValue(final Map map, final Object key) {
        Short shortObject = getShort(map, key);
        if (shortObject == null) {
            return 0;
        }
        return shortObject.shortValue();
    }

    /**
     * Gets an int from a Map in a null-safe manner.
     * <p>
     * The int is obtained from the results of {@link #getNumber(Map,Object)}.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as an int, <code>0</code> if null map input
     */
    public static int getIntValue(final Map map, final Object key) {
        Integer integerObject = getInteger(map, key);
        if (integerObject == null) {
            return 0;
        }
        return integerObject.intValue();
    }

    /**
     * Gets a long from a Map in a null-safe manner.
     * <p>
     * The long is obtained from the results of {@link #getNumber(Map,Object)}.
     *
     * @param map  the map to use
     * @param key  the key to look up
     * @return the value in the Map as a long, <code>0L</code> if null map input
     */
    public static long getLongValue(final Map map, final Object key) {
        Long longObject = getLong(map, key);
        if (longObject == null) {
            return 0L;
        }