Java 如何将JComboBox项与其他项交换？

我正在尝试制作一个货币转换器程序，我希望JComboBox项目从另一个JComboBox中被替换

我知道错误在于尝试将字符串转换为整数，但我看不到其他设置JComboBox内容的方法

以下是jButton的代码：

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
                try {
              for(int a = 0; a < 4; a++){
                String box2 = (currency2.getItemAt(a));
            System.out.println("List items b4 conversion, JComboBox1: "+ currency1.getItemAt(a));
            System.out.println("List items b4 conversion, JComboBox2: "+ box2+"\n");
            System.out.println("--End of first 2 items--");
System.out.println("JComboBox2 after conv" +currency1.getItemAt(Integer.parseInt(box2)));
                }

                    }catch (NumberFormatException e){
                        System.out.println("error");
                }    
    }

---

同时，当我删除：

System.out.println（“conv后的jcombox2”+currency1.getItemAt（Integer.parseInt（box2））

时，它会按预期打印两个jcombox的所有项目。

非常感谢，我真不敢相信这会这么容易！（尴尬地笑）没问题，是这样的：）

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
    String txt1 = (String) JComboBox1.getSelectedItem();
    String txt2 = (String) JComboBox2.getSelectedItem();
    jComboBox1.setSelectedItem(txt2);
    jComboBox2.setSelectedItem(txt1);
}

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
    String txt1 = (String) JComboBox1.getSelectedItem();
    String txt2 = (String) JComboBox2.getSelectedItem();
    jComboBox1.setSelectedItem(txt2);
    jComboBox2.setSelectedItem(txt1);
}