Program: 8600
Project: 8600
Buggy source:
public boolean isLegal(final FaunusElement element){
  Object elementValue=ElementPicker.getProperty(element,this.key);
  if (elementValue instanceof Number)   elementValue=((Number)elementValue).floatValue();
switch (this.compare) {
case EQUAL:
    if (null == elementValue) {
      for (      final Object value : values) {
        if (null == value)         return true;
      }
      return false;
    }
 else {
      for (      final Object value : values) {
        if (elementValue.equals(value))         return true;
      }
      return false;
    }
case NOT_EQUAL:
  if (null == elementValue) {
    for (    final Object value : values) {
      if (null != value)       return true;
    }
    return false;
  }
 else {
    for (    final Object value : values) {
      if (!elementValue.equals(value))       return true;
    }
    return false;
  }
case GREATER_THAN:
if (null == elementValue) {
  return this.nullIsWildcard;
}
 else {
  for (  final Object value : values) {
    if (((Comparable)elementValue).compareTo(value) >= 1)     return true;
  }
  return false;
}
case LESS_THAN:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
  if (((Comparable)elementValue).compareTo(value) <= -1)   return true;
}
return false;
}
case GREATER_THAN_EQUAL:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
if (((Comparable)elementValue).compareTo(value) >= 0) return true;
}
return false;
}
case LESS_THAN_EQUAL:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
if (((Comparable)elementValue).compareTo(value) <= 0) return true;
}
return false;
}
default :
throw new IllegalArgumentException("String_Node_Str");
}
}

Fixed version (ground truth):
public boolean isLegal(final FaunusElement element){
  Object elementValue=ElementPicker.getProperty(element,this.key);
  if (elementValue instanceof Number)   elementValue=((Number)elementValue).floatValue();
switch (this.compare) {
case EQUAL:
    if (null == elementValue) {
      if (this.nullIsWildcard)       return true;
 else {
        for (        final Object value : values) {
          if (null == value)           return true;
        }
      }
      return false;
    }
 else {
      for (      final Object value : values) {
        if (elementValue.equals(value))         return true;
      }
      return false;
    }
case NOT_EQUAL:
  if (null == elementValue) {
    if (this.nullIsWildcard)     return true;
 else {
      for (      final Object value : values) {
        if (null != value)         return true;
      }
    }
    return false;
  }
 else {
    for (    final Object value : values) {
      if (!elementValue.equals(value))       return true;
    }
    return false;
  }
case GREATER_THAN:
if (null == elementValue) {
  return this.nullIsWildcard;
}
 else {
  for (  final Object value : values) {
    if (((Comparable)elementValue).compareTo(value) >= 1)     return true;
  }
  return false;
}
case LESS_THAN:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
  if (((Comparable)elementValue).compareTo(value) <= -1)   return true;
}
return false;
}
case GREATER_THAN_EQUAL:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
if (((Comparable)elementValue).compareTo(value) >= 0) return true;
}
return false;
}
case LESS_THAN_EQUAL:
if (null == elementValue) {
return this.nullIsWildcard;
}
 else {
for (final Object value : values) {
if (((Comparable)elementValue).compareTo(value) <= 0) return true;
}
return false;
}
default :
throw new IllegalArgumentException("String_Node_Str");
}
}