Please fix vulnerability issues in the code - Portability Flaw: Locale Dependent Comparison

Searchable PDF Lambda is one of the lambda in our ML pipeline which need to be placed in production. But there are 4 high vulnerability issues found in the code (2 related with Null Dereferences, 2 Portability Flaw:Locale Dependent Comparison), which need to be FIXED. Please find summary of 'Portability Flaw: Locale Dependent Comparison' issues grouped vertically

Start by reviewing the two vulnerability screenshots and locating the corresponding code in the repository's Java Lambda implementation. The issue does not name files, tests, or entry points, so first map the reported locale-dependent comparisons and null dereferences to source locations. Done means all four reported high-severity findings are fixed and the relevant validation passes.

Written by the indexing model from the issue text.