Helpful NullPointerExceptions — how to read the detail message in production?

Helpful NullPointerExceptions

JDK 14+ enriches NPE messages with which variable was null in the expression chain—dramatically faster root cause in logs without debugger.

• Enabled by default; disable with -XX:-ShowCodeDetailsInExceptionMessages if info leakage concern.
• Shows method, field, and array index in chain.
• Still fix null safety—don't rely on messages in API contracts.
• Works with records and compact stack traces.

// NPE message example:
// Cannot invoke "String.length()" because "user.getName()" is null