Attachment 156209 Details for Bug 279166 – A JFace validator using JSR-303 to validate a single property

A JFace validator using JSR-303 to validate a single property

JSR303Validator.java (text/plain), 5.48 KB, created by Marcus Ilgner

on 2010-01-15 03:59:52 EST

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Filename:

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Creator: Marcus Ilgner

Created: 2010-01-15 03:59:52 EST

Size: 5.48 KB

patch

obsolete

>package com.marcusilgner.research.validation;
>
>import java.util.Iterator;
>import java.util.Set;
>
>import javax.validation.ConstraintViolation;
>import javax.validation.Validation;
>import javax.validation.ValidationException;
>import javax.validation.Validator;
>import javax.validation.ValidatorFactory;
>
>import org.eclipse.core.databinding.validation.IValidator;
>import org.eclipse.core.databinding.validation.ValidationStatus;
>import org.eclipse.core.runtime.IStatus;
>import org.eclipse.jface.fieldassist.ControlDecoration;
>import org.eclipse.jface.fieldassist.FieldDecoration;
>import org.eclipse.jface.fieldassist.FieldDecorationRegistry;
>import org.eclipse.swt.SWT;
>import org.eclipse.swt.widgets.Control;
>
>/**
> * An Eclipse Databinding Validator implementation which uses the JSR303
> * validation API to check a single property for validity. Use as
> * beforeSetValidator, after the value has been converted to the targets
> * property class
> * 
> * Licensed under EPL v1.0 (http://www.eclipse.org/legal/epl-v10.html)
> * 
> * To use, initialize JSR303 first and call setValidatorFactory
> * 
> * If given a control, this validator will also paint a field decoration
> * 
> * @author Marcus Ilgner <mail@marcusilgner.com>
> * 
> * @param <T>
> *            The class of the bean being bound. Not actively used as
> *            {@link javax.validation.Validator#validateValue(Class, String, Object, Class...)}
> *            works somewhat differently than
> *            {@link javax.validation.Validator#validateProperty(Object, String, Class...)}
> *            Should the API be frozen like this, the template class will
> *            probably removed
> */
>public class JSR303Validator<T extends Object> implements IValidator {
>
>	// the bean to be validated
>	private T bean;
>
>	// the name of the bean property to check
>	private String propertyName;
>
>	// a validator to run validation against
>	private Validator validator;
>
>	// will show a field decoration if validation constraints are violated
>	private ControlDecoration controlDecoration;
>
>	// a shared validator factory to be used by all instances of this class
>	private static ValidatorFactory validatorFactory;
>
>	/**
>	 * initializes the validator with a non-default
>	 * javax.validation.ValidatorFactory
>	 * 
>	 * @param _factory
>	 */
>	public static void setValidatorFactory(ValidatorFactory _factory) {
>		validatorFactory = _factory;
>	}
>
>	/**
>	 * simple constructor which doesn't use field decorations JSR303Validator(T,
>	 * String, Control) is recommended
>	 * 
>	 * @param _bean
>	 *            the bean to validate
>	 * @param _propertyName
>	 *            name of the property to be validated
>	 */
>	public JSR303Validator(T _bean, String _propertyName) {
>		bean = _bean;
>		propertyName = _propertyName;
>
>		controlDecoration = null;
>		initValidator();
>	}
>
>	/**
>	 * constructor which constructs a field decoration on the specified control
>	 * 
>	 * @param _bean
>	 *            the bean to validate
>	 * @param _propertyName
>	 *            name of the property to be validated
>	 * @param _control
>	 *            control to receive field decoration on constraint violation
>	 */
>	public JSR303Validator(T _bean, String _propertyName, Control _control) {
>		bean = _bean;
>		propertyName = _propertyName;
>		initValidator();
>		createFieldDecoration(_control);
>	}
>
>	/**
>	 * Creates a field decoration on the given control
>	 * 
>	 * @param _control
>	 *            control to be decorated
>	 */
>	private void createFieldDecoration(Control _control) {
>		controlDecoration = new ControlDecoration(_control, SWT.LEFT
>				| SWT.BOTTOM);
>		FieldDecoration fieldDecoration = FieldDecorationRegistry.getDefault()
>				.getFieldDecoration(FieldDecorationRegistry.DEC_ERROR);
>		controlDecoration.setImage(fieldDecoration.getImage());
>	}
>
>	/**
>	 * Creates a validator. If no javax.validation.ValidatorFactory was set it
>	 * will try to create a factory from defaults
>	 */
>	private void initValidator() {
>		if (validatorFactory == null) {
>			// JSR303 hasn't been initialized. Give it a shot.
>			try {
>				validatorFactory = Validation.buildDefaultValidatorFactory();
>			} catch (Exception e) {
>				throw new ValidationException(
>						"ValidationFactory not set and unable to initialize validation from default values");
>			}
>		}
>		validator = validatorFactory.getValidator();
>
>	}
>
>	/**
>	 * runs the actual validation and shows the decoration if required
>	 */
>	@Override
>	public IStatus validate(Object _value) {
>		Set<?> validationResult = validator.validateValue(bean.getClass(),
>				propertyName, _value, javax.validation.groups.Default.class);
>		if (validationResult.size() > 0) {
>			String message = assembleErrorMessage(validationResult);
>			if (controlDecoration != null) {
>				controlDecoration.setDescriptionText(message);
>				controlDecoration.show();
>			}
>			return ValidationStatus.error(message);
>		}
>		if (controlDecoration != null) {
>			controlDecoration.hide();
>		}
>		return ValidationStatus.ok();
>	}
>
>	/**
>	 * Concatenates the messages from the validationResult into a single
>	 * multi-line string
>	 * 
>	 * @param validationResult
>	 *            a result from calling a JSR303 validation method
>	 * @return
>	 */
>	@SuppressWarnings("unchecked")
>	private String assembleErrorMessage(Set<?> validationResult) {
>		String message = "";
>		Iterator<ConstraintViolation> iterator = (Iterator<ConstraintViolation>) validationResult
>				.iterator();
>		while (iterator.hasNext()) {
>			ConstraintViolation violation = iterator.next();
>			message += violation.getMessage();
>			if (iterator.hasNext()) {
>				message += System.getProperty("line.separator");
>			}
>		}
>		return message;
>	}
>
>}

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Attachments on bug 279166: 156209 | 160643 | 206651