elsupport.java

java属性邦定的（JSR-295）的一个实现

            return new Short(number.shortValue());
        }
        if (Float.TYPE == type || Float.class.equals(type)) {
            return new Float(number.floatValue());
        }

        throw new IllegalArgumentException(MessageFactory.get("error.convert",
                number, number.getClass(), type));
    }

    public final static Number coerceToNumber(final Object obj, final Class type)
            throws IllegalArgumentException {
        if (obj == null || "".equals(obj)) {
            return coerceToNumber(ZERO, type);
        }
        if (obj instanceof String) {
            return coerceToNumber((String) obj, type);
        }
        if (ELArithmetic.isNumber(obj)) {
            return coerceToNumber((Number) obj, type);
        }

        Class objType = obj.getClass();
        if (Character.class.equals(objType) || Character.TYPE == objType) {
            return coerceToNumber(new Short((short) ((Character) obj)
                    .charValue()), type);
        }

        throw new IllegalArgumentException(MessageFactory.get("error.convert",
                obj, objType, type));
    }

    protected final static Number coerceToNumber(final String val,
            final Class type) throws IllegalArgumentException {
        if (Long.TYPE == type || Long.class.equals(type)) {
            return Long.valueOf(val);
        }
        if (Integer.TYPE == type || Integer.class.equals(type)) {
            return Integer.valueOf(val);
        }
        if (Double.TYPE == type || Double.class.equals(type)) {
            return Double.valueOf(val);
        }
        if (BigInteger.class.equals(type)) {
            return new BigInteger(val);
        }
        if (BigDecimal.class.equals(type)) {
            return new BigDecimal(val);
        }
        if (Byte.TYPE == type || Byte.class.equals(type)) {
            return Byte.valueOf(val);
        }
        if (Short.TYPE == type || Short.class.equals(type)) {
            return Short.valueOf(val);
        }
        if (Float.TYPE == type || Float.class.equals(type)) {
            return Float.valueOf(val);
        }

        throw new IllegalArgumentException(MessageFactory.get("error.convert",
                val, String.class, type));
    }

    /**
     * @param obj
     * @return
     */
    public final static String coerceToString(final Object obj) {
        if (obj == null) {
            return "";
        } else if (obj instanceof String) {
            return (String) obj;
        } else if (obj instanceof Enum) {
            return ((Enum) obj).name();
        } else {
            return obj.toString();
        }
    }

    public final static Object coerceToType(final Object obj, final Class type)
            throws IllegalArgumentException {
        if (type == null || Object.class.equals(type)) {
            return obj;
        }
        if (String.class.equals(type)) {
            return coerceToString(obj);
        }
        if (ELArithmetic.isNumberType(type)) {
            return coerceToNumber(obj, type);
        }
        if (Character.class.equals(type) || Character.TYPE == type) {
            return coerceToCharacter(obj);
        }
        if (Boolean.class.equals(type) || Boolean.TYPE == type) {
            return coerceToBoolean(obj);
        }
        if (type.isEnum()) {
            return coerceToEnum(obj, type);
        }
        if (obj != null && type.isAssignableFrom(obj.getClass())) {
            return obj;
        }

        // new to spec
        if (obj == null)
            return null;
        if (obj instanceof String) {
            if ("".equals(obj))
                return null;
            PropertyEditor editor = PropertyEditorManager.findEditor(type);
            if (editor != null) {
                editor.setAsText((String) obj);
                return editor.getValue();
            }
        }
        throw new IllegalArgumentException(MessageFactory.get("error.convert",
                obj, obj.getClass(), type));
    }

    /**
     * @param obj
     * @return
     */
    public final static boolean containsNulls(final Object[] obj) {
        for (int i = 0; i < obj.length; i++) {
            if (obj[0] == null) {
                return true;
            }
        }
        return false;
    }

    public final static boolean isBigDecimalOp(final Object obj0,
            final Object obj1) {
        return (obj0 instanceof BigDecimal || obj1 instanceof BigDecimal);
    }

    public final static boolean isBigIntegerOp(final Object obj0,
            final Object obj1) {
        return (obj0 instanceof BigInteger || obj1 instanceof BigInteger);
    }

    public final static boolean isDoubleOp(final Object obj0, final Object obj1) {
        return (obj0 instanceof Double
                || obj1 instanceof Double
                || obj0 instanceof Float
                || obj1 instanceof Float
                || (obj0 != null && (Double.TYPE == obj0.getClass() || Float.TYPE == obj0
                        .getClass())) || (obj1 != null && (Double.TYPE == obj1
                .getClass() || Float.TYPE == obj1.getClass())));
    }

    public final static boolean isDoubleStringOp(final Object obj0,
            final Object obj1) {
        return (isDoubleOp(obj0, obj1)
                || (obj0 instanceof String && isStringFloat((String) obj0)) || (obj1 instanceof String && isStringFloat((String) obj1)));
    }

    public final static boolean isLongOp(final Object obj0, final Object obj1) {
        return (obj0 instanceof Long
                || obj1 instanceof Long
                || obj0 instanceof Integer
                || obj1 instanceof Integer
                || obj0 instanceof Character
                || obj1 instanceof Character
                || obj0 instanceof Short
                || obj1 instanceof Short
                || obj0 instanceof Byte
                || obj1 instanceof Byte
                || (obj0 != null && (Long.TYPE == obj0.getClass()
                        || Integer.TYPE == obj0.getClass()
                        || Character.TYPE == obj0.getClass()
                        || Short.TYPE == obj0.getClass() || Byte.TYPE == obj0
                        .getClass())) || (obj0 != null && (Long.TYPE == obj0
                .getClass()
                || Integer.TYPE == obj0.getClass()
                || Character.TYPE == obj0.getClass()
                || Short.TYPE == obj0.getClass() || Byte.TYPE == obj0
                .getClass())));
    }

    public final static boolean isStringFloat(final String str) {
        int len = str.length();
        if (len > 1) {
            char c = 0;
            for (int i = 0; i < len; i++) {
                switch (c = str.charAt(i)) {
                case 'E':
                    return true;
                case 'e':
                    return true;
                case '.':
                    return true;
                }
            }
        }
        return false;
    }

    public final static Number toFloat(final String value) {
        try {
            if (Double.parseDouble(value) > Double.MAX_VALUE) {
                return new BigDecimal(value);
            } else {
                return new Double(value);
            }
        } catch (NumberFormatException e0) {
            return new BigDecimal(value);
        }
    }

    public final static Number toNumber(final String value) {
        try {
            return new Integer(Integer.parseInt(value));
        } catch (NumberFormatException e0) {
            try {
                return new Long(Long.parseLong(value));
            } catch (NumberFormatException e1) {
                return new BigInteger(value);
            }
        }
    }

    /**
     * 
     */
    public ELSupport() {
        super();
    }

}