: Oracle hosts archives of older Java versions on their website. You can check there for Java 1.4.0. However, Oracle might require you to create an account or login to download older versions.
If you type into a modern search engine, you will likely find broken links, archived forum posts, and warnings. Why has this version vanished from the official sources? java 1.4 0 download
If you have a non-negotiable business requirement—such as running a specific legacy enterprise resource planning (ERP) system that cannot be upgraded—you will not find the files on the main Oracle Java SE download page. : Oracle hosts archives of older Java versions