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This arguments are supported only JDK less than or equal to 6,
https://docs.oracle.com/cd/E13150_01/jrockit_jvm/jrockit/jrdocs/refman/optionXX.html

G1 collectors are introduced in Java 7, and other GC are made deprecated in Java 8, and removed completely from Java 9.

http://www.oracle.com/technetwork/java/javase/7u4-relnotes-1575007.html

In Java 8, G1 Collectors are used, others are deprecated.