How to write a SqlTimestampPropertyEditor in Spring

Sometimes it is important to have your own PropertyEditor [see http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/validation.html#beans-beans-conversion] in Spring, for example when you want to have SqlTimestamp as property in a bean. For this JavaType spring has no build-in PropertyEditor Implementation.

First step: Implement your SqlTimestampPropertyEditor:

package org.springframework.beans.propertyeditors;

import java.beans.PropertyEditorSupport;
import java.sql.Timestamp;
import java.text.ParseException;
import java.text.SimpleDateFormat;

/**
 * Property editor for java.sql.Timestamp, supporting SimpleDateFormat.
 * 
 * Using default Constructor uses the pattern yyyy-MM-dd
 * Using the constructor with String, you can use your own pattern.
 * 
 */
public class SqlTimestampPropertyEditor extends PropertyEditorSupport {

    public static final String DEFAULT_BATCH_PATTERN = "yyyy-MM-dd";

    private final SimpleDateFormat sdf;

    /**
     * uses default pattern yyyy-MM-dd for date parsing.
     */
    public SqlTimestampPropertyEditor() {
        this.sdf = new SimpleDateFormat(SqlTimestampPropertyEditor.DEFAULT_BATCH_PATTERN);
    }

    /**
     * Uses the given pattern for dateparsing, see {@link SimpleDateFormat} for allowed patterns.
     * 
     * @param pattern
     *            the pattern describing the date and time format
     * @see SimpleDateFormat#SimpleDateFormat(String)
     */
    public SqlTimestampPropertyEditor(String pattern) {
        this.sdf = new SimpleDateFormat(pattern);
    }

    /**
     * @see java.beans.PropertyEditorSupport#setAsText(java.lang.String)
     */
    @Override
    public void setAsText(String text) throws IllegalArgumentException {

        try {
            setValue(new Timestamp(this.sdf.parse(text).getTime()));
        } catch (ParseException ex) {
            throw new IllegalArgumentException("Could not parse date: " + ex.getMessage(), ex);
        }
    }

    /**
     * Format the Timestamp as String, using the specified DateFormat.
     */
    @Override
    public String getAsText() {
        Timestamp value = (Timestamp) getValue();
        return (value != null ? this.sdf.format(value) : "");
    }
}

Second Step: Register the SqlTimestampPropertyEditor
Open your application-context.xml file and define the bean:

  <!-- A Custom Property Editor for SqlTimestamp -->
  <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
    <property name="customEditors">
      <map>
        <entry key="java.sql.Timestamp" value="org.springframework.beans.propertyeditors.SqlTimestampPropertyEditor">
      </map>
    </property>
  </bean>

Third step: Use it in a different bean:

  <bean id="exampleSimpleBean" class="org.springframework.example.SimpleBean">
    <property name="timestamp">
      <value type="java.sql.Timestamp">2008-01-01</value>
    </property>
  </bean>

  <bean id="exampleMapBean" class="org.springframework.example.MapBean">
    <property name="parameterValues">
      <map>
        <entry key="timestamp">
          <value type="java.sql.Timestamp">2008-01-01</value>
        </entry>
      </map>
    </property>
  </bean>

Where the date (2008-01-31) is defined you can also use the spring expression language to access application wide or scope wide variables.

Bean class examples:

org.springframework.example.SimpleBean

package org.springframework.example;

import java.sql.Timestamp;

public class SimpleBean {

    private Timestamp timestamp;

    public Timestamp getTimestamp() {
        return timestamp;
    }

    public void setTimestamp(Timestamp timestamp) {
        this.timestamp = timestamp;
    }
}

org.springframework.example.MapBean

package org.springframework.example;

import java.util.Map;

public class MapBean {

    private Map parameterValues;
    
    public void setParameterValues(Map parameterValues) {
        this.parameterValues = parameterValues;
    }
}

In another article we will see why I need a special SqlTimestampPropertyEditor