Programmatic Validation

Here we demonstrate programmatic validation in the event handler onValidateFromInputs(). Yes, we could have avoided it by using Bean Validation's @Pattern annotation instead.

(required, maxLength=10, letters only)

(required, maxLength=10, letters only)

References: Bean Validation, @Pattern API, Forms and Validation, Form.

Home


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!-- We need a doctype to allow us to use special characters like &nbsp; 
     We use a "strict" DTD to make IE follow the alignment rules. -->
     
<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
<body class="container">
    <h3>Programmatic Validation</h3>
    
    Here we demonstrate programmatic validation in the event handler <code>onValidateFromInputs()</code>. 
    Yes, we could have avoided it by using Bean Validation's <code>@Pattern</code> annotation instead.

    <div class="eg">
        <t:form  class="form-horizontal" t:id="inputs">
        
            <div class="form-group">
                <t:label for="firstName" class="col-sm-3"/>
                <div class="col-sm-3">
                    <t:textfield t:id="firstName"/>
                </div>
                <div class="col-sm-6">
                    <p class="form-control-static">
                        ${firstName}
                        <span class="text-muted">
                            (required, maxLength=10, letters only)
                        </span>
                    </p>
                </div>
            </div>
            <div class="form-group">
                <t:label for="lastName" class="col-sm-3"/>
                <div class="col-sm-3">
                    <t:textfield t:id="lastName"/>
                </div>
                <div class="col-sm-6">
                    <p class="form-control-static">
                        ${lastName}
                        <span class="text-muted">
                            (required, maxLength=10, letters only)
                        </span>
                    </p>
                </div>
            </div>
            <div class="form-group">
                <div class="col-sm-3 col-sm-offset-3">
                    <t:submit/>
                </div>
            </div>

        </t:form>
    </div>

    References: 
    <a href="http://tapestry.apache.org/bean-validation.html">Bean Validation</a>, 
    <a href="http://docs.oracle.com/javaee/6/api/javax/validation/constraints/Pattern.html">@Pattern API</a>, 
    <a href="http://tapestry.apache.org/forms-and-validation.html">Forms and Validation</a>, 
    <a href="http://tapestry.apache.org/5.4/apidocs/org/apache/tapestry5/corelib/components/Form.html">Form</a>.<br/><br/>
    
    <t:pagelink page="Index">Home</t:pagelink><br/><br/>
        
    <t:tabgroup>
        <t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/input/ProgrammaticValidation.tml"/>
        <t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/input/ProgrammaticValidation.java"/>
        <t:sourcecodetab src="/web/src/main/resources/META-INF/assets/css/examples/plain.css"/>
    </t:tabgroup>
</body>
</html>



package jumpstart.web.pages.examples.input;

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

import org.apache.tapestry5.PersistenceConstants;
import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.InjectComponent;
import org.apache.tapestry5.annotations.Persist;
import org.apache.tapestry5.annotations.Property;
import org.apache.tapestry5.corelib.components.Form;
import org.apache.tapestry5.corelib.components.TextField;

@Import(stylesheet = "css/examples/plain.css")
public class ProgrammaticValidation {

    // Screen fields

    @Property
    @Persist(PersistenceConstants.FLASH)
    @NotNull
    @Size(max = 10)
    private String firstName;

    @Property
    @Persist(PersistenceConstants.FLASH)
    @NotNull
    @Size(max = 10)
    private String lastName;

    // Generally useful bits and pieces

    @InjectComponent("inputs")
    private Form form;

    @InjectComponent("firstName")
    private TextField firstNameField;

    @InjectComponent("lastName")
    private TextField lastNameField;

    // The code

    void onValidateFromInputs() {

        // Error if the names don't contain letters only

        if (firstName != null) {
            if (!firstName.matches("[A-Za-z]+")) {
                form.recordError(firstNameField, "First Name must contain letters only");
            }
        }

        if (lastName != null) {
            if (!lastName.matches("[A-Za-z]+")) {
                form.recordError(lastNameField, "Last Name must contain letters only");
            }
        }
    }

}



.eg {
                margin: 20px 0;
                padding: 14px;
                border: 1px solid #ddd;
                border-radius: 6px;
                -webkit-border-radius: 6px;
                -mox-border-radius: 6px;
}