如何检查GUI中的文本字段是否包含某些内容？

Question

我试图检查用户在文本字段中的输入是否包含某些字母，如果有，则让它增加一个计数器。

//this is the code for the button
//tfYourName is the name of the text field
//below is what I've tried already
private void btnResultsMouseClicked(java.awt.event.MouseEvent evt) {   
    if (tfYourName.getSelectedItems.toString.toUpperCase().contains("T"))
}   

Answer 1

if (tfYourName.getText().toUpperCase().contains("T"))
    counter++;