If you are reading this, you probably aren’t building a new startup. Instead, you are likely staring at a very old, very critical piece of enterprise software—perhaps a manufacturing control system, an old banking applet, or a legacy ERP module—that refuses to run on anything newer than "Java 1.5."
Released in 2004, Java 2 Platform Standard Edition 5.0 (internally versioned 1.5.0 ) introduced game-changers like Generics, Enums, and the for-each loop. But today, finding the official JRE for version 1.5 is like finding a vintage vinyl record; it takes patience and caution. java 1.5 runtime environment download
Create a .bat (Windows) or .sh (Linux) script that explicitly calls the old Java: If you are reading this, you probably aren’t