Example usage for java.beans PropertyEditor getValue

List of usage examples for java.beans PropertyEditor getValue

Introduction

In this page you can find the example usage for java.beans PropertyEditor getValue.

Prototype


Object getValue();

Source Link

Document

Gets the property value.

Usage

From source file:org.nextframework.controller.ExtendedBeanWrapper.java

/**
 * Convert the value to the required type (if necessary from a String),
 * for the specified property.//w  w  w  .j  a  v a  2s  . c  om
 * @param propertyName name of the property
 * @param oldValue previous value, if available (may be <code>null</code>)
 * @param newValue proposed change value
 * @param requiredType the type we must convert to
 * (or <code>null</code> if not known, for example in case of a collection element)
 * @return the new value, possibly the result of type conversion
 * @throws TypeMismatchException if type conversion failed
 */
protected Object doTypeConversionIfNecessary(String propertyName, String fullPropertyName, Object oldValue,
        Object newValue, Class requiredType) throws TypeMismatchException {

    Object convertedValue = newValue;
    if (convertedValue != null) {

        // Custom editor for this type?
        PropertyEditor pe = findCustomEditor(requiredType, fullPropertyName);

        // Value not of required type?
        if (pe != null || (requiredType != null
                && (requiredType.isArray() || !requiredType.isAssignableFrom(convertedValue.getClass())))) {

            if (requiredType != null) {
                if (pe == null) {
                    // No custom editor -> check BeanWrapperImpl's default editors.
                    pe = (PropertyEditor) this.defaultEditors.get(requiredType);
                    if (pe == null) {
                        // No BeanWrapper default editor -> check standard JavaBean editors.
                        pe = PropertyEditorManager.findEditor(requiredType);
                    }
                }
            }

            if (pe != null && !(convertedValue instanceof String)) {
                // Not a String -> use PropertyEditor's setValue.
                // With standard PropertyEditors, this will return the very same object;
                // we just want to allow special PropertyEditors to override setValue
                // for type conversion from non-String values to the required type.
                try {
                    pe.setValue(convertedValue);
                    Object newConvertedValue = pe.getValue();
                    if (newConvertedValue != convertedValue) {
                        convertedValue = newConvertedValue;
                        // Reset PropertyEditor: It already did a proper conversion.
                        // Don't use it again for a setAsText call.
                        pe = null;
                    }
                } catch (IllegalArgumentException ex) {
                    throw new TypeMismatchException(
                            createPropertyChangeEvent(fullPropertyName, oldValue, newValue), requiredType, ex);
                }
            }

            if (requiredType != null && !requiredType.isArray() && convertedValue instanceof String[]) {
                // Convert String array to a comma-separated String.
                // Only applies if no PropertyEditor converted the String array before.
                // The CSV String will be passed into a PropertyEditor's setAsText method, if any.
                if (logger.isDebugEnabled()) {
                    logger.debug("Converting String array to comma-delimited String [" + convertedValue + "]");
                }
                convertedValue = StringUtils.arrayToCommaDelimitedString((String[]) convertedValue);
            }

            if (pe != null && convertedValue instanceof String) {
                // Use PropertyEditor's setAsText in case of a String value.
                if (logger.isDebugEnabled()) {
                    logger.debug(
                            "Converting String to [" + requiredType + "] using property editor [" + pe + "]");
                }
                try {
                    pe.setValue(oldValue);
                    pe.setAsText((String) convertedValue);
                    convertedValue = pe.getValue();
                } catch (IllegalArgumentException ex) {
                    throw new TypeMismatchException(
                            createPropertyChangeEvent(fullPropertyName, oldValue, newValue), requiredType, ex);
                }
            }

            if (requiredType != null) {
                // Array required -> apply appropriate conversion of elements.
                if (requiredType.isArray()) {
                    Class componentType = requiredType.getComponentType();
                    if (convertedValue instanceof Collection) {
                        // Convert Collection elements to array elements.
                        Collection coll = (Collection) convertedValue;
                        Object result = Array.newInstance(componentType, coll.size());
                        int i = 0;
                        for (Iterator it = coll.iterator(); it.hasNext(); i++) {
                            Object value = doTypeConversionIfNecessary(propertyName,
                                    propertyName + PROPERTY_KEY_PREFIX + i + PROPERTY_KEY_SUFFIX, null,
                                    it.next(), componentType);
                            Array.set(result, i, value);
                        }
                        return result;
                    } else if (convertedValue != null && convertedValue.getClass().isArray()) {
                        // Convert Collection elements to array elements.
                        int arrayLength = Array.getLength(convertedValue);
                        Object result = Array.newInstance(componentType, arrayLength);
                        for (int i = 0; i < arrayLength; i++) {
                            Object value = doTypeConversionIfNecessary(propertyName,
                                    propertyName + PROPERTY_KEY_PREFIX + i + PROPERTY_KEY_SUFFIX, null,
                                    Array.get(convertedValue, i), componentType);
                            Array.set(result, i, value);
                        }
                        return result;
                    } else {
                        // A plain value: convert it to an array with a single component.
                        Object result = Array.newInstance(componentType, 1);
                        Object value = doTypeConversionIfNecessary(propertyName,
                                propertyName + PROPERTY_KEY_PREFIX + 0 + PROPERTY_KEY_SUFFIX, null,
                                convertedValue, componentType);
                        Array.set(result, 0, value);
                        return result;
                    }
                }

                // If the resulting value definitely doesn't match the required type,
                // try field lookup as fallback. If no matching field found,
                // throw explicit TypeMismatchException with full context information.
                if (convertedValue != null && !requiredType.isPrimitive()
                        && !requiredType.isAssignableFrom(convertedValue.getClass())) {

                    // In case of String value, try to find matching field (for JDK 1.5
                    // enum or custom enum with values defined as static fields).
                    if (convertedValue instanceof String) {
                        try {
                            Field enumField = requiredType.getField((String) convertedValue);
                            return enumField.get(null);
                        } catch (Exception ex) {
                            logger.debug("Field [" + convertedValue + "] isn't an enum value", ex);
                        }
                    }

                    // Definitely doesn't match: throw TypeMismatchException.
                    throw new TypeMismatchException(
                            createPropertyChangeEvent(fullPropertyName, oldValue, newValue), requiredType);
                }
            }
        }
    }

    if (requiredType != null && List.class.isAssignableFrom(requiredType)) { //treat conventions of enum lists
        Type genericReturnType = getPropertyDescriptorInternal(fullPropertyName).getReadMethod()
                .getGenericReturnType();
        if (genericReturnType instanceof ParameterizedType) {
            Type actualType = ((ParameterizedType) genericReturnType).getActualTypeArguments()[0];
            if (actualType instanceof Class && convertedValue != null) {
                List list = (List) convertedValue;
                for (int i = 0; i < list.size(); i++) {
                    Object o = list.remove(i);
                    o = doTypeConversionIfNecessary(o, (Class) actualType);
                    list.add(i, o);
                }
            }
        }
    }

    return convertedValue;
}