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."

, this version was a massive leap for Java back in 2004, introducing features like generics and annotations

FROM centos:4 COPY jre-1_5_0_22-linux-i586-rpm.bin /tmp/ RUN /tmp/jre-1_5_0_22-linux-i586-rpm.bin

Most applications written for Java 1.5 will run perfectly on Java 8, 11, or 17. However, some specific legacy applications—particularly those using deprecated sun.* internal APIs, specific garbage collection tuning from 2005, or cryptographic libraries from that era—may break on modern runtimes. For these rare cases, you need the original runtime.