Testing difference (subtraction) of lengths to imply @SameLen

[mernst]

Consider the below test case.
Without the @AssumeAssertion, the Index Checker issues the warning.

MethodComparator.java:23: error: [array.access.unsafe.high] Potentially unsafe array access: the index could be larger than the array's bound
      result = ptypes1[i].toString().compareTo(ptypes2[i].toString());
                                                       ^
  found   : @LTLengthOf(value="ptypes1", offset="0") int
  required: @IndexFor("ptypes2") or @LTLengthOf("ptypes2") -- an integer less than ptypes2's length
1 error

I think that comparing the subtraction (difference) of array lengths is somewhat common in compare and compareTo methods.

import java.lang.reflect.Method;
import java.util.Comparator;

public class MethodComparator implements Comparator<Method> {

  @Override
  public int compare(Method m1, Method m2) {
    Class<?>[] ptypes1 = m1.getParameterTypes();
    Class<?>[] ptypes2 = m2.getParameterTypes();
    int result;
    result = ptypes1.length - ptypes2.length;
    if (result != 0) {
      return result;
    }
    assert ptypes1.length == ptypes2.length : "@AssumeAssertion(index): difference of lengths is 0";
    for (int i = 0; i < ptypes1.length; i++) {
      result = ptypes1[i].toString().compareTo(ptypes2[i].toString());
      if (result != 0) {
        return result;
      }
    }
    return result;
  }
}