BeanUtility.java Source code

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Here is the source code for BeanUtility.java

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/*
 * StringUtil.java
 *
 * Created on May 7, 2004, 7:43 PM
 *
 * Copyright (C) 2004  Robert Cooper, Temple of the Screaming Penguin
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
import java.beans.*;
import java.lang.reflect.*;

/** This class contains some generic methods for working with String.
 * @version $Rev: 87 $
 * @author  <a href="mailto:cooper@screaming-penguin.com">Robert Cooper</a>
 */
public class BeanUtility {

    /** Creates a new instance of StringUtil */
    private BeanUtility() {
    }

    /** This method takes a JavaBean and generates a standard toString() type result for it.
     * @param o JavaBean object to stringinate
     * @return STRINGIATION! Stringingating the countryside. Stringinating all the peasants.
     */
    public static String beanToString(Object o) {
        StringBuffer result = new StringBuffer();
        if (o == null)
            return "--- null";
        result.append("--- begin");
        result.append(o.getClass().getName());
        result.append(" hash: ");
        result.append(o.hashCode());
        result.append("\r\n");
        try {
            PropertyDescriptor[] pds = Introspector.getBeanInfo(o.getClass()).getPropertyDescriptors();
            for (int pdi = 0; pdi < pds.length; pdi++) {
                try {
                    result.append(
                            "Property: " + pds[pdi].getName() + " Value: " + pds[pdi].getReadMethod().invoke(o));
                } catch (IllegalAccessException iae) {
                    result.append("Property: " + pds[pdi].getName() + " (Illegal Access to Value) ");
                } catch (InvocationTargetException iae) {
                    result.append(
                            "Property: " + pds[pdi].getName() + " (InvocationTargetException) " + iae.toString());
                } catch (Exception e) {
                    result.append("Property: " + pds[pdi].getName() + " (Other Exception )" + e.toString());
                }
                result.append("\r\n");
            }

        } catch (IntrospectionException ie) {
            result.append("Introspection Exception: " + ie.toString());
            result.append("\r\n");
        }
        result.append("--- end ");
        result.append(o.getClass().getName());
        result.append(" hash: ");
        result.append(o.hashCode());
        result.append("\n");
        return result.toString();
    }

    /** This method takes 2 JavaBeans of the same type and copies the properties of one bean to the other.
     * Any attempts that have an IllegalAccessException will be ignored. This will also NOT recurse into nested bean
     * results. References to existing beanage will be includes. Try using .clone() for that stuff.
     * @param from Source Bean
     * @param to Desitnation Bean
     */
    public static void copyBeanToBean(Object from, Object to)
            throws InvocationTargetException, IntrospectionException {
        PropertyDescriptor[] pds = Introspector.getBeanInfo(from.getClass()).getPropertyDescriptors();
        for (int i = 0; i < pds.length; i++) {
            try {
                if (pds[i].getName().equals("class"))
                    continue;
                Object[] value = { pds[i].getReadMethod().invoke(from) };
                pds[i].getWriteMethod().invoke(to, value);
            } catch (IllegalAccessException iae) {
                //Im just going to ignore any properties I don't have access too.
            }
        }

    }

    public static String[] getPropertyNames(Object o) throws IntrospectionException {
        PropertyDescriptor[] pds = Introspector.getBeanInfo(o.getClass()).getPropertyDescriptors();
        String[] propertyNames = new String[pds.length];
        for (int i = 0; i < pds.length; i++) {
            propertyNames[i] = pds[i].getName();
        }
        return propertyNames;
    }

    public static Object getProperty(Object o, String propertyName) throws Exception {
        PropertyDescriptor[] pds = Introspector.getBeanInfo(o.getClass()).getPropertyDescriptors();
        for (int i = 0; i < pds.length; i++) {
            if (pds[i].getName().equals(propertyName)) {
                return pds[i].getReadMethod().invoke(o);
            }
        }
        throw new Exception("Property not found.");
    }

    public static void setProperty(Object o, String propertyName, Object value) throws Exception {
        PropertyDescriptor[] pds = Introspector.getBeanInfo(o.getClass()).getPropertyDescriptors();
        for (int i = 0; i < pds.length; i++) {
            if (pds[i].getName().equals(propertyName)) {
                pds[i].getWriteMethod().invoke(o, value);
                return;
            }
        }
        throw new Exception("Property not found.");
    }

    public static Class getPropertyType(Object o, String propertyName) throws Exception {
        PropertyDescriptor[] pds = Introspector.getBeanInfo(o.getClass()).getPropertyDescriptors();
        for (int i = 0; i < pds.length; i++) {
            if (pds[i].getName().equals(propertyName)) {
                return pds[i].getPropertyType();
            }
        }
        throw new Exception("Property not found.");
    }
}