Java - checking if parseInt throws exception

Question

I'm wondering how to do something only if Integer.parseInt(whatever) doesn't fail.

More specifically I have a jTextArea of user specified values seperated by line breaks.

I want to check each line to see if can be converted to an int.

Figured something like this, but it doesn't work:

for(int i = 0; i < worlds.jTextArea1.getLineCount(); i++){                     if(Integer.parseInt(worlds.jTextArea1.getText(worlds.jTextArea1.getLineStartOffset(i),worlds.jTextArea1.getLineEndOffset(i)) != (null))){}  } 

Any help appreciated.

Answer 1

Check if it is integer parseable

public boolean isInteger(String string) {     try {         Integer.valueOf(string);         return true;     } catch (NumberFormatException e) {         return false;     } } 

or use Scanner

Scanner scanner = new Scanner("Test string: 12.3 dog 12345 cat 1.2E-3");  while (scanner.hasNext()) {     if (scanner.hasNextDouble()) {         Double doubleValue = scanner.nextDouble();     } else {         String stringValue = scanner.next();     } } 

or use Regular Expression like

private static Pattern doublePattern = Pattern.compile("-?\\d+(\\.\\d*)?");  public boolean isDouble(String string) {     return doublePattern.matcher(string).matches(); } 

Answer 2

public static boolean isParsable(String input) {     try {         Integer.parseInt(input);         return true;     } catch (final NumberFormatException e) {         return false;     } }