List of Java bytecode instructions: Difference between revisions

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{{Short description|none}} <!-- This short description is INTENTIONALLY "none" - please see WP:SDNONE before you consider changing it! -->

{{Main|Java bytecode}}

This is a list of the instructions that make up the [[Java bytecode]], an abstract machine language that is ultimately executed by the [[Java virtual machine]].<ref>{{cite web|url=https://docs.oracle.com/javase/specs/jvms/se12se24/html/index.html |title=The Java® Virtual Machine Specification – Java SE 1224 Edition |access-date=MayJuly 2226, 20212025}}</ref> The Java bytecode is generated from languages running on the [[Java Platform]], most notably the [[Java (programming language)|Java programming language]].

''Note that any referenced "value" refers to a 32-bit int as per the Java instruction set.''

Line 754 ⟶ 755:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if references are equal, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_acmpne

Line 761 ⟶ 762:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if references are not equal, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmpeq

Line 768 ⟶ 769:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ints are equal, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmpge

Line 775 ⟶ 776:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ''value1'' is greater than or equal to ''value2'', branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmpgt

Line 782 ⟶ 783:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ''value1'' is greater than ''value2'', branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmple

Line 789 ⟶ 790:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ''value1'' is less than or equal to ''value2'', branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmplt

Line 796 ⟶ 797:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ''value1'' is less than ''value2'', branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|if_icmpne

Line 803 ⟶ 804:

|2: branchbyte1, branchbyte2

|value1, value2 →

|if ints are not equal, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifeq

Line 810 ⟶ 811:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifge

Line 817 ⟶ 818:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is greater than or equal to 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifgt

Line 824 ⟶ 825:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is greater than 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifle

Line 831 ⟶ 832:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is less than or equal to 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|iflt

Line 838 ⟶ 839:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is less than 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifne

Line 845 ⟶ 846:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is not 0, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifnonnull

Line 852 ⟶ 853:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is not null, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|ifnull

Line 859 ⟶ 860:

|2: branchbyte1, branchbyte2

|value →

|if ''value'' is null, branch to instruction at ''branchoffset'' (signed short constructed from unsigned bytes ({{mono|branchbyte1 &lt;&lt; 8 {{pipe}} branchbyte2}})

|-

|iinc

Line 1,458 ⟶ 1,459:

|}

{{Refbegin}}

{{note label|Deprecated|†||Deprecated in Java 7 (major class version 51).<ref>{{cite web|url=https://docs.oracle.com/javase/specs/jvms/se8se24/html/jvms-4.html#jvms-4.9.1 |title=Chapter 4. The class File Format 4.9.1. Static Constraints |access-date=MayJuly 2226, 20212025}}</ref> They will not appear in class files generated from a compiler newer than that. <code>ret</code> is not explicitly deprecated, but useless without the <code>jsr</code> and <code>jsr_w</code> opcodes.}}

{{Refend}}

Line 1,469 ⟶ 1,470:

== External links ==

*[https://docs.oracle.com/javase/specs/jvms/se12se24/html/jvms-6.html The Java Virtual Machine Instruction Set]

{{Java (Sun)}}