json을 취득, 표시하는 어플리케이션 3

import groovy.swing.SwingBuilder
import javax.swing.*
import java.awt.*

def cbMethod
def txtUrl
def txtJson

def sendRequest = {
    def conn = txtUrl.text.toURL().openConnection()
    conn.requestMethod = cbMethod.selectedItem

    txtJson.text = conn.inputStream.text
}

new SwingBuilder().frame(title:'jsonを取得、表示するアプリケーション', defaultCloseOperation:JFrame.EXIT_ON_CLOSE,
                        size: [800, 600], show:true) {
    lookAndFeel('nimbus')
    borderLayout()
    hbox(constraints: BorderLayout.NORTH) {
        cbMethod = comboBox(items:['GET', 'POST'])
        txtUrl = textField()
        button(text:'送信', actionPerformed:sendRequest)
    }
    scrollPane(constraints: BorderLayout.CENTER) {
        txtJson = textArea(editable:false)
    }
}