how do i add a drop down list item in a mule connector?

问题

I've made a mule connector, everything works great. I got 4 main properties for an HTTP outbound connection: url, port, path and method.

I would like the method to be a drop down list with values: GET, POST.

Do you guys know how to do it? what annotation needs to be used in case that's the way to solve it? Or is it recognized by Mule when adding a Map or Enum property?

This is my current simple code

/**
 * This file was automatically generated by the Mule Development Kit
 */
package com.web.testcomponent;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import org.mule.api.MuleEventContext;
import org.mule.api.annotations.Configurable;
import org.mule.api.annotations.Module;
import org.mule.api.annotations.Processor;
import org.mule.api.annotations.display.Placement;
import org.mule.api.annotations.expressions.Lookup;
import org.mule.api.annotations.param.Default;
import org.mule.api.annotations.param.Optional;
import org.mule.api.annotations.param.Payload;

/**
 * Generic module
 *
 * @author MuleSoft, Inc.
 */
@Module(name="testcomponent", schemaVersion="1.0-SNAPSHOT", friendlyName="HTTP/S Component", description="This is custom HTTP/S Component")
public class TestComponentModule
{

    @Lookup("myMuleContext")
    private MuleEventContext context;

    /**
     * Connection URL
     */
    @Configurable
    @Placement(order=1,group="Connection",tab="General")
    private String url;

    /**
     * Connection Port
     */
    @Configurable
    @Placement(order=2,group="Connection",tab="General")
    private String port;

    /**
     * Connection Path
     */
    @Configurable
    @Placement(order=3,group="Connection",tab="General")
    private String path;    

    /**
     * Connection Method (GET or POST)
     */
    @Configurable
    @Default(value="GET")
    @Optional
    @Placement(order=4,group="Connection",tab="General")
    private String method;

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getPort() {
        return port;
    }

    public void setPort(String port) {
        this.port = port;
    }

    public String getPath() {
        return path;
    }

    public void setPath(String path) {
        this.path = path;
    }

    public String getMethod() {
        return method;
    }

    public void setMethod(String method) {
        this.method = method;
    }

    public MuleEventContext getContext() {
        return context;
    }

    public void setContext(MuleEventContext context) {
        this.context = context;
    }

    /**
     * Custom processor
     *
     * {@sample.xml ../../../doc/TestComponent-connector.xml.sample testcomponent:test-processor}
     *
     * @param content Random content to be processed
     * @param payload The String payload itself
     * @return Some string
     */
    @Processor
    public String testProcessor(@Payload String payload)
    {       
        HttpURLConnection conn = null;

        try {
            URL url = new URL(getUrl() + "/" + getPath());
            conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod(getMethod());
            conn.setRequestProperty("Accept", "application/json");

            if(conn.getResponseCode() != HttpURLConnection.HTTP_OK) {
                throw new RuntimeException("Failed -> HTTP error code : " + conn.getResponseCode());
            }

            BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            String output, buffer;
            output = "";
            while((buffer = br.readLine()) != null) {
                output += buffer;
            }

            payload = output;
            conn.disconnect();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return payload;
    }
}

回答1:

I have no problem using an enum:

public enum HttpMethod
{
    GET, POST
};

@Configurable
@Default(value = "GET")
@Optional
@Placement(order = 4, group = "Connection", tab = "General")
private HttpMethod method;

Doesn't this work for you too?

As a side note, looking at what your @Processor method does, I'm wondering if you're not re-inventing @RestCall processors. Also why using a raw HttpURLConnection when you can perform HTTP calls with the MuleClient?

来源：https://stackoverflow.com/questions/17473105/how-do-i-add-a-drop-down-list-item-in-a-mule-connector