Hitting class class art.Test1979$Transform[FOO: value of , BAR: value of ] Initial: class art.Test1979$Transform[FOO: value of , BAR: value of ] Reading with reflection. public static java.lang.Object art.Test1979$Transform.BAR = (ID: 0) value of public static java.lang.Object art.Test1979$Transform.FOO = (ID: 1) value of Reading normally. Read BAR field: (ID: 0) value of Read FOO field: (ID: 1) value of Redefined: class art.Test1979$Transform[FOO: value of , BAR: value of , BAZ: null] Reading with reflection after possible modification. public static java.lang.Object art.Test1979$Transform.BAR = (ID: 0) value of public static java.lang.Object art.Test1979$Transform.BAZ = (ID: 2) public static java.lang.Object art.Test1979$Transform.FOO = (ID: 1) value of Reading normally after possible modification. Read FOO field: (ID: 1) value of Read BAR field: (ID: 0) value of