BeanForm

<span jwcid="@BeanForm" bean="ognl:pojo" save="listener:save" delete="listener:delete"/>

<span jwcid="@BeanForm" bean="ognl:pojo" properties="ognl:'name,email,comment'" save="listener:save" cancel="listener:cancel" refresh="listener:refresh" />

<div jwcid="commentBeanFieldBlock@Block">
	<input jwcid="commentBeanField@TextArea" value="ognl:pojo.comment" displayName="message:comment"/>
</div>

<span jwcid="@BeanForm" bean="ognl:pojo" properties="ognl:'name{required},email{required,email},comment'" save="listener:save" delegate="bean:validationDelegate" clientValidationEnabled="ognl:true"/>

<!-- If this component is already inside a form, don't render another form. -->
<span jwcid="isInsideAForm">
	<span jwcid="renderBlock1"/>
</span>
<span jwcid="isNotInsideAForm">
	<form jwcid="beanForm">
		<span jwcid="renderBlock2"/>
	</form>
</span>

<!-- The main content block. -->
<span jwcid="block">
	<table class="beanFormTable">
		<span jwcid="beanPropertyRow">
			<span jwcid="hasCustomField">
				<td class="beanFormLeftColumn"><span jwcid="customFieldLabel"/></td>
				<td class="beanFormRightColumn"><span jwcid="customFieldBlock"/></td>
			</span>
			<span jwcid="noCustomField">
				<span jwcid="isString">
					<td class="beanFormLeftColumn"><span jwcid="beanPropertyLabel_Text"/></td>
					<td class="beanFormRightColumn"><span jwcid="beanPropertyField_Text"/></td>
				</span>
				<span jwcid="isBoolean">
					<td class="beanFormLeftColumn"><span jwcid="beanPropertyLabel_Checkbox"/></td>
					<td class="beanFormRightColumn"><span jwcid="beanPropertyField_Checkbox"/></td>
				</span>
				<span jwcid="isNumber">
					<td class="beanFormLeftColumn"><span jwcid="beanPropertyLabel_Number"/></td>
					<td class="beanFormRightColumn"><span jwcid="beanPropertyField_Number"/></td>
				</span>
				<span jwcid="isDate">
					<td class="beanFormLeftColumn"><span jwcid="beanPropertyLabel_Date"/></td>
					<td class="beanFormRightColumn"><span jwcid="beanPropertyField_Date"/></td>
				</span>
			</span>
		</span>
		<td colspan="2" class="beanFormButtonColumn">
			<span jwcid="hasSave"><span jwcid="beanFormSave"/></span>
			<span jwcid="hasCancel"><span jwcid="beanFormCancel" onclick="this.form.events.cancel()"/></span>
			<span jwcid="hasRefresh"><span jwcid="beanFormRefresh" onclick="this.form.events.refresh()"/></span>
			<span jwcid="hasDelete"><span jwcid="beanFormDelete"/></span>
		</td>
	</table>
</span>

package com.diphy.web.components;

import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.beans.SimpleBeanInfo;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.hivemind.Location;
import org.apache.tapestry.BaseComponent;
import org.apache.tapestry.IComponent;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.TapestryUtils;
import org.apache.tapestry.annotations.InjectObject;
import org.apache.tapestry.binding.BindingFactory;
import org.apache.tapestry.components.Block;
import org.apache.tapestry.form.IFormComponent;
import org.apache.tapestry.form.validator.ValidatorsBinding;

import com.diphy.util.Logger;

/**
 * <p>A form that provides edit capabilities for a Java Bean. Only properties
 * that are strings, booleans, numbers or dates are considered editable. Fields
 * for read-only bean properties are automatically disabled. Field labels are
 * messages keyed on the property name. The save button (if displayed) is
 * labeled with the message corresponding to the key <tt>save</tt>. The cancel
 * button (if displayed) is labeled with the message corresponding to the key
 * <tt>cancel</tt>. The refresh button (if displayed) is labeled with the
 * message corresponding to the key <tt>refresh</tt>. The delete button (if
 * displayed) is labeled with the message corresponding to the key
 * <tt>delete</tt>.</p>
 *
 * <p>The component parameters are as follows:</p>
 *
 * <ul>
 *   <li><tt>bean</tt>: Required, specifies the Java Bean to modify.</li>
 *   <li><tt>properties</tt>: Not required, specifies the bean properties to be
 *      edited; if omitted, all eligible bean properties (strings, booleans,
 *      numbers and dates) are considered editable; if specified, properties
 *      are displayed in the specified order.</li>
 *   <li><tt>save</tt>: Not required, specifies the listener to invoke on
 *      save.</li>
 *   <li><tt>delete</tt>: Not required, specifies the listener to invoke on
 *      delete.</li>
 *   <li><tt>success</tt>: Not required, specifies the listener to invoke on
 *      form submission.</li>
 *   <li><tt>cancel</tt>: Not required, specifies the listener to invoke on
 *      form cancellation.</li>
 *   <li><tt>refresh</tt>: Not required, specifies the listener to invoke on
 *      form refresh.</li>
 *   <li><tt>delegate</tt>: Not required, specifies the validation delegate to
 *      use on the form.</li>
 *   <li>And all the rest of the <tt>Form</tt> parameters, including
 *      <tt>method</tt>, <tt>listener</tt>, <tt>stateful</tt>, <tt>direct</tt>,
 *      <tt>clientValidationEnabled</tt>, <tt>focus</tt>, <tt>scheme</tt> and
 *      <tt>port</tt>. See the <tt>Form</tt> component's documentation for
 *      more details.
 * </ul>
 *
 * <p>The generated HTML is a form containing a two-column table, unless this
 * component is inside an external Form component, in which case no extraneous
 * form is generated. The table's left column contains the field labels and the
 * right column contains the data entry fields. The bottom row spans both
 * columns and contains the save button (if the <tt>save</tt> parameter was
 * specified), the cancel button (if the <tt>cancel</tt> parameter was
 * specified), the refresh button (if the <tt>refresh</tt> parameter was
 * specified) and the delete button (if the <tt>delete</tt> parameter was
 * specified).</p>
 *
 * <p>The table can be styled using CSS: the table's CSS class is
 * <tt>beanFormTable</tt>, the left column's CSS class is
 * <tt>beanFormLeftColumn</tt>, the right column's CSS class is
 * <tt>beanFormRightColumn</tt>, and the bottom column that contains the
 * buttons has the CSS class <tt>beanFormButtonColumn</tt>.</p>
 *
 * <p>If you need to customize any of the input fields, you can do so by adding
 * a <tt>Block</tt> component to your page (with the id
 * <tt>[propertyName]BeanFieldBlock</tt>) that contains any
 * <tt>IFormComponent</tt> (with the id <tt>[propertyName]BeanField</tt>).
 * Doing this will allow you to edit properties that are considered
 * non-editable by default (ie, not a string/boolean/number/date).</p>
 *
 * <p>In order to use validation, specify the <tt>delegate</tt> parameter
 * (unless you have already specified it in an external <tt>Form</tt> component
 * that contains this component) and add standard validation lists to the
 * <tt>properties</tt> parameter, in between squiggly brackets (<tt>{}</tt>).
 * See below for an example.</p>
 *
 * <p>Usage examples:</p>
 * <ul>
 *   <li>Minimal: <tt>&lt;span jwcid="@BeanForm" bean="ognl:pojo"
 *      save="listener:save"/&gt;</tt></li>
 *   <li>More: <tt>&lt;span jwcid="@BeanForm" bean="ognl:pojo"
 *      properties="ognl:'name,email,comment'" save="listener:save"
 *      cancel="listener:cancel" delete="listener:delete"
 *      refresh="listener:refresh" /&gt;</tt></li>
 *   <li>To edit the <tt>comment</tt> property in a text area you would add the
 *      following to your page:<br>
 *      <tt>&lt;div jwcid="commentBeanFieldBlock@Block"&gt;</tt><br>
 *      <tt>&lt;input jwcid="commentBeanField@TextArea"
 *         value="ognl:pojo.comment"
 *         displayName="message:comment"/&gt;</tt><br>
 *      <tt>&lt;/div&gt;</tt><br>
 *      </tt></li>
 *   <li>To make <tt>name</tt> and <tt>email</tt> required, and check that
 *      <tt>email</tt> is actually an email:
 *      <tt>&lt;span jwcid="@BeanForm" bean="ognl:pojo"
 *      properties="ognl:'name{required},email{required,email},comment'"
 *      save="listener:save" clientValidationEnabled="ognl:true"
 *      delegate="bean:validationDelegate"/&gt;</tt></li>
 * </ul>
 *
 * @author Daniel Gredler
 * @version 1.2
 */
public abstract class BeanForm extends BaseComponent {

	private final static Logger LOG = Logger.getLogger( BeanForm.class );
	private final static Pattern PROPERTIES_PATTERN = Pattern.compile( "\\s*(\\w+)\\s*(?:\\{\\s*(.+?)\\s*\\}\\s*)?,?" );
	private final static String CUSTOM_FIELD_BLOCK_SUFFIX = "BeanFieldBlock";
	private final static String CUSTOM_FIELD_SUFFIX = "BeanField";

	@InjectObject( "infrastructure:requestCycle" )
	public abstract IRequestCycle getCycle();

	@InjectObject( "service:tapestry.form.validator.ValidatorsBindingFactory" )
	public abstract BindingFactory getValidatorsBindingFactory();

	public abstract Object getBean();
	public abstract void setBean( Object bean );

	public abstract String getProperties();
	public abstract void setProperties( String properties );

	public List<BeanProperty> getBeanProperties() {
		List<BeanProperty> properties = new ArrayList<BeanProperty>();
		Object bean = this.getBean();
		BeanInfo info = this.getBeanInfo();
		PropertyDescriptor[] descriptors = info.getPropertyDescriptors();
		for( PropertyDescriptor descriptor : descriptors ) {
			BeanProperty property = new BeanProperty( descriptor );
			String validators = this.getValidators( property );
			property.setValidators( validators );
			if( this.isIncluded( property ) ) {
				if( property.isEditableType() || this.hasCustomField( property ) ) {
					properties.add( property );
				}
				else if( this.hasExplicitProperties() ) {
					LOG.warn( "Explicitly included bean property '" + property.getName() + "' is not a " +
						"string/boolean/number/date, and a custom field was not specified for it." );
				}
			}
		}
		properties = this.reorderProperties( properties );
		if( LOG.isDebugEnabled() ) {
			LOG.debug( "Found " + properties.size() + " editable properties for bean " + bean + ": " + properties );
		}
		return properties;
	}

	public boolean isInsideAForm() {
		try {
			TapestryUtils.getForm( this.getCycle(), this );
			return true;
		}
		catch( ApplicationRuntimeException e ) {
			return false;
		}
	}

	public List getValidatorList( BeanProperty property, IComponent component ) {
		String name = property.getName();
		String desc = "dynamic validators binding for bean property " + name;
		String expression = property.getValidators();
		Location location = component.getLocation();
		BindingFactory factory = this.getValidatorsBindingFactory();
		ValidatorsBinding binding = (ValidatorsBinding) factory.createBinding( component, desc, expression, location );
		List validators = (List) binding.getObject();
		if( LOG.isDebugEnabled() ) {
			LOG.debug( "Bean property '" + name + "' has " + validators.size() + " validators: " + validators );
		}
		return validators;
	}

	public boolean hasCustomField( BeanProperty property ) {
		boolean customBlock = this.getCustomFieldBlock( property ) != null;
		boolean customField = this.getCustomField( property ) != null;
		return customBlock && customField;
	}

	public Block getCustomFieldBlock( BeanProperty property ) {
		return (Block) this.getComponent( property, CUSTOM_FIELD_BLOCK_SUFFIX, Block.class );
	}

	public IFormComponent getCustomField( BeanProperty property ) {
		return (IFormComponent) this.getComponent( property, CUSTOM_FIELD_SUFFIX, IFormComponent.class );
	}

	@SuppressWarnings( "unchecked" )
	private IComponent getComponent( BeanProperty property, String suffix, Class clazz ) {
		IComponent component = null;
		String name = property.getName() + suffix;
		Map components = this.getPage().getComponents();
		if( components.containsKey( name ) ) {
			IComponent candidate = (IComponent) components.get( name );
			if( clazz.isInstance( candidate ) ) {
				component = candidate;
			}
			else {
				LOG.error( "Component '" + candidate.getId() + "' should be of type " + clazz.getName() + "!" );
			}
		}
		return component;
	}

	private BeanInfo getBeanInfo() {
		Object bean = this.getBean();
		BeanInfo info;
		if( bean != null ) {
			try {
				info = Introspector.getBeanInfo( bean.getClass() );
			}
			catch( IntrospectionException e ) {
				LOG.error( e );
				info = new SimpleBeanInfo();
			}
		}
		else {
			LOG.warn( "BeanForm's bean is null!" );
			info = new SimpleBeanInfo();
		}
		return info;
	}

	private List<String> explicitPropertyNames;
	private Map<String, String> explicitPropertyValidators;

	private String getValidators( BeanProperty property ) {
		this.initExplicitProperties();
		if( this.explicitPropertyValidators == null ) return null;
		return this.explicitPropertyValidators.get( property.getName() );
	}

	private boolean isIncluded( BeanProperty property ) {
		this.initExplicitProperties();
		if( this.explicitPropertyNames == null ) return true;
		return this.explicitPropertyNames.contains( property.getName() );
	}

	private List<BeanProperty> reorderProperties( List<BeanProperty> properties ) {
		this.initExplicitProperties();
		if( this.explicitPropertyNames == null ) return properties;
		List<BeanProperty> orderedProperties = new ArrayList<BeanProperty>( properties.size() );
		for( String name : this.explicitPropertyNames ) {
			for( BeanProperty property : properties ) {
				if( property.getName().equals( name ) ) {
					orderedProperties.add( property );
				}
			}
		}
		return orderedProperties;
	}

	private boolean hasExplicitProperties() {
		this.initExplicitProperties();
		return ( this.explicitPropertyNames != null );
	}

	private synchronized void initExplicitProperties() {
		if( this.explicitPropertyNames != null ) return;
		String s = this.getProperties();
		if( s == null ) return;
		this.explicitPropertyNames = new ArrayList<String>();
		this.explicitPropertyValidators = new HashMap<String, String>();
		Matcher m = PROPERTIES_PATTERN.matcher( s );
		while( m.find() ) {
			String name = m.group( 1 );
			String validators = m.group( 2 );
			this.explicitPropertyNames.add( name );
			this.explicitPropertyValidators.put( name, validators );
		}
	}

	/**
	 * Instances of this class get serialized into the HTML, so keep it trim (ie,
	 * as few serialized instance variables as possible).
	 */
	public static class BeanProperty implements Serializable {

		private static final long serialVersionUID = -9064407627959060313L;

		private static final String STRING = String.class.getName();
		private static final String BOOLEAN = Boolean.class.getName();
		private static final String BOOL = boolean.class.getName();
		private static final String INTEGER = Integer.class.getName();
		private static final String INT = int.class.getName();
		private static final String LONG = Long.class.getName();
		private static final String LNG = long.class.getName();
		private static final String FLOAT = Float.class.getName();
		private static final String FLT = float.class.getName();
		private static final String DOUBLE = Double.class.getName();
		private static final String DBL = double.class.getName();
		private static final String DATE = Date.class.getName();

		private String name;
		private String validators;
		private boolean readOnly;
		private String typeName;

		public BeanProperty( PropertyDescriptor descriptor ) {
			this.name = descriptor.getName();
			this.validators = null;
			this.readOnly = descriptor.getWriteMethod() == null;
			this.typeName = descriptor.getPropertyType().getName();
		}

		public String getName() {
			return this.name;
		}

		public String getValidators() {
			return this.validators;
		}

		public void setValidators( String validators ) {
			this.validators = validators;
		}

		public boolean isReadOnly() {
			return this.readOnly;
		}

		public String getTypeName() {
			return this.typeName;
		}

		public boolean isString() {
			return STRING.equals( this.typeName );
		}

		public boolean isBoolean() {
			return BOOLEAN.equals( this.typeName ) || BOOL.equals( this.typeName );
		}

		public boolean isNumber() {
			return INTEGER.equals( this.typeName ) || INT.equals( this.typeName ) ||
				LONG.equals( this.typeName ) || LNG.equals( this.typeName ) ||
				FLOAT.equals( this.typeName ) || FLT.equals( this.typeName ) ||
				DOUBLE.equals( this.typeName ) || DBL.equals( this.typeName );
		}

		public boolean isDate() {
			return DATE.equals( this.typeName );
		}

		public boolean isEditableType() {
			return this.isString() || this.isBoolean() || this.isNumber() || this.isDate();
		}

		@Override
		public String toString() {
			return this.name + ( this.validators != null ? "{" + this.validators + "}" : "" );
		}

	}

}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE component-specification PUBLIC
	"-//Apache Software Foundation//Tapestry Specification 4.0//EN"
	"http://jakarta.apache.org/tapestry/dtd/Tapestry_4_0.dtd">

<component-specification class="com.diphy.web.components.BeanForm" allow-body="no" allow-informal-parameters="yes">

	<description>A form that provides edit capabilities for a Java Bean.</description>

	<parameter name="bean" required="true"/>
	<parameter name="properties" required="false"/>
	<parameter name="save" required="false"/>
	<parameter name="delete" required="false"/>

	<parameter name="method" required="false"/>
	<parameter name="success" required="false"/>
	<parameter name="cancel" required="false"/>
	<parameter name="refresh" required="false"/>
	<parameter name="listener" required="false"/>
	<parameter name="stateful" required="false"/>
	<parameter name="direct" required="false"/>
	<parameter name="delegate" required="false"/>
	<parameter name="clientValidationEnabled" required="false"/>
	<parameter name="focus" required="false"/>
	<parameter name="scheme" required="false"/>
	<parameter name="port" required="false"/>

	<property name="beanProperty"/>

	<component id="isInsideAForm" type="If">
		<binding name="condition" value="isInsideAForm()"/>
	</component>
	<component id="isNotInsideAForm" type="Else"/>

	<component id="block" type="Block"/>
	<component id="renderBlock1" type="RenderBlock">
		<binding name="block" value="component:block"/>
	</component>
	<component id="renderBlock2" type="RenderBlock">
		<binding name="block" value="component:block"/>
	</component>

	<component id="beanForm" type="Form">
		<binding name="method" value="method"/>
		<binding name="success" value="success"/>
		<binding name="cancel" value="cancel"/>
		<binding name="refresh" value="refresh"/>
		<binding name="listener" value="listener"/>
		<binding name="stateful" value="stateful"/>
		<binding name="direct" value="direct"/>
		<binding name="delegate" value="delegate"/>
		<binding name="clientValidationEnabled" value="clientValidationEnabled"/>
		<binding name="focus" value="focus"/>
		<binding name="scheme" value="scheme"/>
		<binding name="port" value="port"/>
	</component>
	<component id="beanPropertyRow" type="For">
		<binding name="source" value="beanProperties"/>
		<binding name="value" value="beanProperty"/>
		<binding name="element" value="'tr'"/>
	</component>

	<component id="hasCustomField" type="If">
		<binding name="condition" value="hasCustomField(beanProperty)"/>
	</component>
	<component id="noCustomField" type="Else"/>

	<component id="customFieldLabel" type="FieldLabel">
		<binding name="field" value="getCustomField(beanProperty)"/>
	</component>
	<component id="customFieldBlock" type="RenderBlock">
		<binding name="block" value="getCustomFieldBlock(beanProperty)"/>
	</component>

	<component id="isString" type="If">
		<binding name="condition" value="beanProperty.isString()"/>
	</component>
	<component id="isBoolean" type="If">
		<binding name="condition" value="beanProperty.isBoolean()"/>
	</component>
	<component id="isNumber" type="If">
		<binding name="condition" value="beanProperty.isNumber()"/>
	</component>
	<component id="isDate" type="If">
		<binding name="condition" value="beanProperty.isDate()"/>
	</component>

	<component id="beanPropertyLabel_Text" type="FieldLabel">
		<binding name="field" value="component:beanPropertyField_Text"/>
	</component>
	<component id="beanPropertyField_Text" type="TextField">
		<binding name="value" value="(beanProperty.name)(bean)"/>
		<binding name="disabled" value="beanProperty.readOnly"/>
		<binding name="displayName" value="getMessage(beanProperty.name)"/>
		<binding name="validators" value="getValidatorList(beanProperty,#this)"/>
	</component>

	<component id="beanPropertyLabel_Checkbox" type="FieldLabel">
		<binding name="field" value="component:beanPropertyField_Checkbox"/>
	</component>
	<component id="beanPropertyField_Checkbox" type="Checkbox">
		<binding name="value" value="(beanProperty.name)(bean)"/>
		<binding name="disabled" value="beanProperty.readOnly"/>
		<binding name="displayName" value="getMessage(beanProperty.name)"/>
		<binding name="validators" value="getValidatorList(beanProperty,#this)"/>
	</component>

	<component id="beanPropertyLabel_Number" type="FieldLabel">
		<binding name="field" value="component:beanPropertyField_Number"/>
	</component>
	<component id="beanPropertyField_Number" type="TextField">
		<binding name="value" value="(beanProperty.name)(bean)"/>
		<binding name="disabled" value="beanProperty.readOnly"/>
		<binding name="displayName" value="getMessage(beanProperty.name)"/>
		<binding name="validators" value="getValidatorList(beanProperty,#this)"/>
	</component>

	<component id="beanPropertyLabel_Date" type="FieldLabel">
		<binding name="field" value="component:beanPropertyField_Date"/>
	</component>
	<component id="beanPropertyField_Date" type="DatePicker">
		<binding name="value" value="(beanProperty.name)(bean)"/>
		<binding name="disabled" value="beanProperty.readOnly"/>
		<binding name="displayName" value="getMessage(beanProperty.name)"/>
		<binding name="validators" value="getValidatorList(beanProperty,#this)"/>
	</component>

	<component id="hasSave" type="If">
		<binding name="condition" value="save!=null"/>
	</component>
	<component id="hasCancel" type="If">
		<binding name="condition" value="cancel!=null"/>
	</component>
	<component id="hasRefresh" type="If">
		<binding name="condition" value="refresh!=null"/>
	</component>
	<component id="hasDelete" type="If">
		<binding name="condition" value="delete!=null"/>
	</component>

	<component id="beanFormSave" type="Submit">
		<binding name="label" value="message:save"/>
		<binding name="listener" value="save"/>
	</component>
	<component id="beanFormCancel" type="Button">
		<binding name="label" value="message:cancel"/>
	</component>
	<component id="beanFormRefresh" type="Button">
		<binding name="label" value="message:refresh"/>
	</component>
	<component id="beanFormDelete" type="Submit">
		<binding name="label" value="message:delete"/>
		<binding name="listener" value="delete"/>
	</component>

</component-specification>