topic Re: Java Expression for tMap in Talend Studio

Java Expression for tMap

Anonymous — Sat, 16 Nov 2024 13:25:11 GMT

Hi, I am still new to Talend and have been looking over the documentation and forum posts for an answer to this problem.
I have created a new Routine in Code.
Code : Routines : resolveName 0.1

package routines;
public class resolveName {
    public static String helloExample(String name) {
    	String str = "fish";
    	return str;
    }
}

The code simply returns fish for what ever the input. I am now trying to use this in a tMap expression builder, I look at the list of categories and it's not listed. What do I have to do to get it to show up? I have restarted Talend after saving.
The other question I've got is for more complex Expressions entered directly into the tMap expression builder, how do I use something like a switch?

switch(row1.name) {
  case 1: output X; break;
  case 2: output Y: break;
  default: output Z;
}

I'm not sure what to code for the 'Output X/Y/Z' bit.
Thanks for any help you can offer.

Re: Java Expression for tMap

Anonymous — Wed, 26 May 2010 22:48:55 GMT

hi ncooper and welcome
when you create a new routine and you want that appear in the menu(list) follow the default example :

/*
 * user specification: the function's comment should contain keys as follows: 1. write about the function's comment.but
 * it must be before the "{talendTypes}" key.
 * 
 * 2. {talendTypes} 's value must be talend Type, it is required . its value should be one of: String, char | Character,
 * long | Long, int | Integer, boolean | Boolean, byte | Byte, Date, double | Double, float | Float, Object, short |
 * Short
 * 
 * 3. {Category} define a category for the Function. it is required. its value is user-defined .
 * 
 * 4. {param} 's format is: {param} <type> <name>
 * 
 * <type> 's value should be one of: string, int, list, double, object, boolean, long, char, date. <name>'s value is the
 * Function's parameter name. the {param} is optional. so if you the Function without the parameters. the {param} don't
 * added. you can have many parameters for the Function.
 * 
 * 5. {example} gives a example for the Function. it is optional.
 */

anyway you can call your static function like that :

yourRoutine.yourStaticFunction(param)

for the second issue you can wrap your switch code in a routine and return the expected value.
ps : in your case do nothing except return default value !
hope it helps you
regards
laurent

Re: Java Expression for tMap

Anonymous — Thu, 27 May 2010 09:38:06 GMT

Thank you for replying, I now have it working.
I will include the comment below.

    /**
     * String() Converts a string to junk
     * 
     * {talendTypes} string | String
     * 
     * {Category} importResolver
     * 
     * {param} string() name: string value
     * 
     * {example} String('Cat'):string
     * 
     */