Refactor: Add null check, optimize string joining, and add JavaDocs#3663

ilayaperumalg merged 2 commits intospring-projects:mainspring-projects/spring-ai:mainfrom

KoreaNirsa:refactor/getTextContent-joining-and-null-checkKoreaNirsa/spring-ai:refactor/getTextContent-joining-and-null-checkCopy head branch name to clipboard