java - Testing whether an input is a number -


i have program, whenever type , hit enter, prints out in window (it's command prompt). however, due few problems calculator function i'm trying add, if user input number, want totally ignore 

    input = new jtextfield();     input.seteditable(true);     input.setforeground(color.white);     input.setcaretcolor(color.white);     input.setopaque(false);      input.addactionlistener(new actionlistener(){          public void actionperformed(actionevent e) {              string text = input.gettext();              if (text.length() >= 1){                  print(text + "\n", false);                  docommand(text);                 scrollbottom();                 input.selectall();             }          }     });

you check if text number regex that:

text.matches("[1-9][0-9]*");

i hope helps.


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