/*
* Copyright 2006-2012 The Scriptella Project Team.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package scriptella.configuration;
import scriptella.core.SystemException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;
/**
* Base class for configuration elements.
*/
public abstract class XmlConfigurableBase implements XmlConfigurable {
private Location location;
protected void setRequiredProperty(final XmlElement element,
final String attribute, final String property) {
setProperty(element, attribute, property);
assertRequiredFieldPresent(element, attribute, property);
}
/**
* @see #setProperty(XmlElement, String, String)
*/
protected void setProperty(final XmlElement element, final String attribute) {
setProperty(element, attribute, attribute);
}
/**
* Sets property on this object using attribute value.
*
* @param element element to get attribute.
* @param attribute attribute name
* @param property property name.
*/
protected void setProperty(final XmlElement element,
final String attribute, final String property) {
String attributeValue = element.getAttribute(attribute);
try {
final Method method = findSetter(property);
method.invoke(this, attributeValue);
} catch (Exception e) {
throw new ConfigurationException("Unable to set property " +
property + " from attribute " + attribute, e, element);
}
}
/**
* @see #setPatternProperty(XmlElement, String, String)
*/
protected void setPatternProperty(final XmlElement element, final String property) {
setPatternProperty(element, property, property);
}
/**
* Sets {@link Pattern} property on this object using attribute value.
*
* @param element element to get attribute.
* @param attribute attribute name
* @param property property name.
*/
protected void setPatternProperty(final XmlElement element,
final String attribute, final String property) {
String ptrStr = element.getAttribute(attribute);
Pattern ptr = null;
if (ptrStr != null) {
try {
//We use multiline+case insensitive patterns
ptr = Pattern.compile(ptrStr, Pattern.CASE_INSENSITIVE + Pattern.DOTALL);
} catch (Exception e) {
throw new ConfigurationException("Attribute " + attribute + " requires valid regular expression, but was: " +
ptrStr, e, element);
}
}
try {
final Method method = getClass().getMethod(
"set" + Character.toUpperCase(property.charAt(0)) + property.substring(1), Pattern.class);
method.invoke(this, ptr);
} catch (Exception e) {
throw new ConfigurationException("Unable to set property " +
property + " from attribute " + attribute, e, element);
}
}
protected Method findSetter(final String property)
throws NoSuchMethodException {
//TODO Add methods cache
return getClass()
.getMethod("set" +
Character.toUpperCase(property.charAt(0)) + property.substring(1),
String.class);
}
protected Method findGetter(final String property)
throws NoSuchMethodException {
return getClass()
.getMethod("get" + Character.toUpperCase(property.charAt(0)) + property.substring(1));
}
protected void setRequiredProperty(final XmlElement element,
final String attribute) {
setRequiredProperty(element, attribute, attribute);
}
protected <T> T loadClass(final XmlElement element, final String attribute,
final Class<T> spec) {
final String h = element.getAttribute(attribute);
if (h == null) {
return null;
}
Class c = null;
try {
c = Class.forName(h);
} catch (ClassNotFoundException e) {
throw new scriptella.configuration.ConfigurationException(
"Invalid class " + h, e, element);
}
if (!spec.isAssignableFrom(c)) {
throw new scriptella.configuration.ConfigurationException("Class " +
c + " doesn't implement " + spec, element);
}
try {
return (T) c.newInstance();
} catch (Exception e) {
throw new scriptella.configuration.ConfigurationException(
"Unable to instantiate class " + c, element);
}
}
protected <T extends XmlConfigurable> List<T> load(
final List<XmlElement> elements, final Class<T> clazz) {
if (elements == null) {
return null;
}
List<T> l = new ArrayList<T>(elements.size());
for (XmlElement element : elements) {
try {
T t = clazz.newInstance();
t.configure(element);
l.add(t);
} catch (InstantiationException e) {
throw new SystemException(e);
} catch (IllegalAccessException e) {
throw new SystemException(e);
}
}
return l;
}
protected void assertRequiredFieldPresent(final XmlElement element,
final String attribute, final String property) {
try {
final Method getter = findGetter(property);
if (getter.invoke(this, (Object[]) null) == null) {
throw new RequiredAttributeException(attribute, element);
}
} catch (ConfigurationException e) {
throw e;
} catch (Exception e) {
throw new RequiredAttributeException(attribute, e, element);
}
}
protected void assertRequiredFieldPresent(final XmlElement element,
final String property) {
assertRequiredFieldPresent(element, property, property);
}
/**
* Called by elements wishing to report their location in XML.
*
* @param element element to calculate location
*/
protected void setLocation(XmlElement element) {
location = new Location(element.getXPath());
}
protected void setLocation(Location location) {
this.location = location;
}
protected Location getLocation() {
return location;
}
}