Fail kelas Java

Fail kelas Java ialah sebuah fail dengan sambungan fail .class mengandungi kod bait Java yang boleh dilakukan pada mesin maya Java (JVM).

Susun atur umum

ofset bait	saiz	jenis atau nilai	penerangan
0	4 bytes	u1 = 0xCA hex	angka ajaib (CAFEBABE) bagi menentukan fail mengikut format fail kelas
1		u1 = 0xFE hex
2		u1 = 0xBA hex
3		u1 = 0xBE hex
4	2 bait	u2	nombor versi minor bagi format fail kelas yang dipakai
5
6	2 bait	u2	nombor versi major bagi format fail kelas yang dipakai. Java SE 13 = 57 (0x39 hex), Java SE 12 = 56 (0x38 hex), Java SE 11 = 55 (0x37 hex), Java SE 10 = 54 (0x36 hex),[1] Java SE 9 = 53 (0x35 hex),[2] Java SE 8 = 52 (0x34 hex), Java SE 7 = 51 (0x33 hex), Java SE 6.0 = 50 (0x32 hex), Java SE 5.0 = 49 (0x31 hex), JDK 1.4 = 48 (0x30 hex), JDK 1.3 = 47 (0x2F hex), JDK 1.2 = 46 (0x2E hex), JDK 1.1 = 45 (0x2D hex). Maklumat nombor-nombor versi yang lebih awal tercata di nota kaki 1 di The JavaTM Virtual Machine Specification 2nd edition
7
8	2 bait	u2	bilangan constant pool, bilangan entri dalam jadual constant pool berikut. This count is at least one greater than the actual number of entries; see following discussion.
9
10	cpsize (variable)	table	constant pool table, an array of variable-sized constant pool entries, containing items such as literal numbers, strings, and references to classes or methods. Indexed starting at 1, containing (constant pool count - 1) number of entries in total (see note).
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10+cpsize	2 bytes	u2	access flags, a bitmask
11+cpsize
12+cpsize	2 bytes	u2	identifies this class, index into the constant pool to a "Class"-type entry
13+cpsize
14+cpsize	2 bytes	u2	identifies super class, index into the constant pool to a "Class"-type entry
15+cpsize
16+cpsize	2 bytes	u2	interface count, number of entries in the following interface table
17+cpsize
18+cpsize	isize (variable)	table	interface table: a variable-length array of constant pool indexes describing the interfaces implemented by this class
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18+cpsize+isize	2 bytes	u2	field count, number of entries in the following field table
19+cpsize+isize
20+cpsize+isize	fsize (variable)	table	field table, variable length array of fields each element is a field_info structure defined in https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.5
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20+cpsize+isize+fsize	2 bytes	u2	method count, number of entries in the following method table
21+cpsize+isize+fsize
22+cpsize+isize+fsize	msize (variable)	table	method table, variable length array of methods each element is a method_info structure defined in https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.6
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22+cpsize+isize+fsize+msize	2 bytes	u2	attribute count, number of entries in the following attribute table
23+cpsize+isize+fsize+msize
24+cpsize+isize+fsize+msize	asize (variable)	table	attribute table, variable length array of attributes each element is an attribute_info structure defined in https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7
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Jika anda melihat rencana yang menggunakan templat {{tunas}} ini, gantikanlah dengan templat tunas yang lebih spesifik.

1. http://www.oracle.com/technetwork/java/javase/10-relnote-issues-4108729.html#Remaining
2. https://bugs.openjdk.java.net/browse/JDK-8148785