Consider source code like:
public class DiagnosticPosition {

    public static void main(String[] args) {
        int i = args[0].
                lengthX;
        int j = args[0].
                length(1);
    }
}

Compiling this leads to:
$ javac DiagnosticPosition.java
DiagnosticPosition.java:4: error: cannot find symbol
        int i = args[0].
                       ^
  symbol: variable lengthX
  location: class String
DiagnosticPosition.java:6: error: no suitable method found for length(int)
        int j = args[0].
                       ^
    method CharSequence.length() is not applicable
      (actual and formal argument lists differ in length)
    method String.length() is not applicable
      (actual and formal argument lists differ in length)
2 errors

The caret marker is not placed appropriately - it refers to the names that are not visible (as they are on the next line).

This is with:
$ javac -fullversion
javac full version "1.8.0-b132"