GUAC-830: Move parsing/formatting into field types.

guacamole-ext/src/main/java/org/glyptodon/guacamole/form/DateField.java

@@ -22,6 +22,11 @@
 
 package org.glyptodon.guacamole.form;
 
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
 /**
  * Represents a date field. The field may contain only date values which
  * conform to a standard pattern, defined by DateField.FORMAT.
@@ -45,4 +50,48 @@ public class DateField extends Field {
         super(name, Field.Type.DATE);
     }
 
+    /**
+     * Converts the given date into a string which follows the format used by
+     * date fields.
+     *
+     * @param date
+     *     The date value to format, which may be null.
+     *
+     * @return
+     *     The formatted date, or null if the provided time was null.
+     */
+    public static String format(Date date) {
+        DateFormat dateFormat = new SimpleDateFormat(DateField.FORMAT);
+        return date == null ? null : dateFormat.format(date);
+    }
+
+    /**
+     * Parses the given string into a corresponding date. The string must
+     * follow the standard format used by date fields, as defined by FORMAT
+     * and as would be produced by format().
+     *
+     * @param dateString
+     *     The date string to parse, which may be null.
+     *
+     * @return
+     *     The date corresponding to the given date string, or null if the
+     *     provided date string was null or blank.
+     *
+     * @throws ParseException
+     *     If the given date string does not conform to the standard format
+     *     used by date fields.
+     */
+    public static Date parse(String dateString)
+            throws ParseException {
+
+        // Return null if no date provided
+        if (dateString == null || dateString.isEmpty())
+            return null;
+
+        // Parse date according to format
+        DateFormat dateFormat = new SimpleDateFormat(DateField.FORMAT);
+        return dateFormat.parse(dateString);
+
+    }
+
 }

guacamole-ext/src/main/java/org/glyptodon/guacamole/form/NumericField.java

@@ -39,4 +39,46 @@ public class NumericField extends Field {
         super(name, Field.Type.NUMERIC);
     }
 
+    /**
+     * Formats the given integer in the format required by a numeric field.
+     *
+     * @param i
+     *     The integer to format, which may be null.
+     *
+     * @return
+     *     A string representation of the given integer, or null if the given
+     *     integer was null.
+     */
+    public static String format(Integer i) {
+
+        if (i == null)
+            return null;
+
+        return i.toString();
+
+    }
+
+    /**
+     * Parses the given string as an integer, where the given string is in the
+     * format required by a numeric field.
+     *
+     * @param str
+     *     The string to parse as an integer, which may be null.
+     *
+     * @return
+     *     The integer representation of the given string, or null if the given
+     *     string was null.
+     *
+     * @throws NumberFormatException
+     *     If the given string is not in a parseable format.
+     */
+    public static Integer parse(String str) throws NumberFormatException {
+
+        if (str == null || str.isEmpty())
+            return null;
+
+        return new Integer(str);
+
+    }
+
 }

guacamole-ext/src/main/java/org/glyptodon/guacamole/form/TimeField.java

@@ -22,6 +22,11 @@
 
 package org.glyptodon.guacamole.form;
 
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
 /**
  * Represents a time field. The field may contain only time values which
  * conform to a standard pattern, defined by TimeField.FORMAT.
@@ -45,4 +50,48 @@ public class TimeField extends Field {
         super(name, Field.Type.TIME);
     }
 
+    /**
+     * Parses the given string into a corresponding time. The string must
+     * follow the standard format used by time fields, as defined by
+     * FORMAT and as would be produced by format().
+     *
+     * @param timeString
+     *     The time string to parse, which may be null.
+     *
+     * @return
+     *     The time corresponding to the given time string, or null if the
+     *     provided time string was null or blank.
+     *
+     * @throws ParseException
+     *     If the given time string does not conform to the standard format
+     *     used by time fields.
+     */
+    public static Date parse(String timeString)
+            throws ParseException {
+
+        // Return null if no time provided
+        if (timeString == null || timeString.isEmpty())
+            return null;
+
+        // Parse time according to format
+        DateFormat timeFormat = new SimpleDateFormat(TimeField.FORMAT);
+        return timeFormat.parse(timeString);
+
+    }
+
+    /**
+     * Converts the given time into a string which follows the format used by
+     * time fields.
+     *
+     * @param time
+     *     The time value to format, which may be null.
+     *
+     * @return
+     *     The formatted time, or null if the provided time was null.
+     */
+    public static String format(Date time) {
+        DateFormat timeFormat = new SimpleDateFormat(TimeField.FORMAT);
+        return time == null ? null : timeFormat.format(time);
+    }
+
 }

guacamole-ext/src/main/java/org/glyptodon/guacamole/form/TimeZoneField.java

@@ -40,4 +40,27 @@ public class TimeZoneField extends Field {
         super(name, Field.Type.TIMEZONE);
     }
 
+    /**
+     * Parses the given string into a time zone ID string. As these strings are
+     * equivalent, the only transformation currently performed by this function
+     * is to ensure that a blank time zone string is parsed into null.
+     *
+     * @param timeZone
+     *     The time zone string to parse, which may be null.
+     *
+     * @return
+     *     The ID of the time zone corresponding to the given string, or null
+     *     if the given time zone string was null or blank.
+     */
+    public static String parse(String timeZone) {
+
+        // Return null if no time zone provided
+        if (timeZone == null || timeZone.isEmpty())
+            return null;
+
+        // Otherwise, assume time zone is valid
+        return timeZone;
+
+    }
+
 }