The Battle of the Java Sea in 1942 was a major victory for the Imperial Japanese Navy. The recently published Senshi Sösho volume 26, The Operation of the Navy in the Dutch East Indies and the Bay of Bengal, contains translated Japanese sources which give insight into Japanese tactics and the Naval Command's appreciation of the battle. The course of the battle proved to be a rude awakening for the Japanese as it put their whole outranging tactic and torpedo tactic into question.