Access Transformers - Revision history

ChampionAsh5357: Update to 1.19

2022-06-18T14:39:55Z

Update to 1.19

ChampionAsh5357: Update to 1.19

2022-06-18T14:39:10Z

Update to 1.19

SciWhiz12: /* Background */ fix link to Encapsulation

2021-12-31T23:55:37Z

Background: fix link to Encapsulation

SciWhiz12: /* Background */ switch same-package and subclasses

2021-10-17T17:00:06Z

Background: switch same-package and subclasses

SciWhiz12: add missing parenthesis

2021-08-29T13:50:28Z

add missing parenthesis

SciWhiz12: whoops, switched the two wildcards

2021-08-13T03:06:51Z

whoops, switched the two wildcards

SciWhiz12: add note about wildcard ATs

2021-08-13T02:56:33Z

add note about wildcard ATs

SciWhiz12: add note about inner classes and $ separator

2021-08-13T02:36:50Z

add note about inner classes and $ separator

SciWhiz12: no to java highlighting

2021-08-13T02:29:56Z

no to java highlighting

SciWhiz12: Rewrite page to be more 'wiki' in tone and more descriptive in nature, remove under construction header

2021-08-13T02:28:30Z

Rewrite page to be more 'wiki' in tone and more descriptive in nature, remove under construction header

Show changes

@@ Line 55: / Line 55: @@
 One solution is to use Java [[:wikipedia:reflection|reflection]] to reflectively access these fields and methods during runtime, but they suffer from some problems:
 * Reflection is slower than regular method calls or field accesses, as certain optimizations done by the JVM cannot be applied.<ref>[https://docs.oracle.com/javase/tutorial/reflect/index.html The Java™ Tutorials: The Reflection API]: ''"Consequently, reflective operations have slower performance than their non-reflective counterparts, and should be avoided in sections of code which are called frequently in performance-sensitive applications."''</ref> This makes reflection unsuitable for performance-critical code, such as during rendering.
-* Reflection cannot allow the modification of <code>final</code> fields which are either marked <code>static</code> or belong to a record class.<ref>[https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/reflect/AccessibleObject.html#setAccessible(boolean) Java 16 javadocs] for <code>java.lang.reflect.AccessibleObject.setAccessible(boolean)</code></ref>
+* Reflection cannot allow the modification of <code>final</code> fields which are either marked <code>static</code> or belong to a record class.<ref>[https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/reflect/AccessibleObject.html#setAccessible(boolean) Java 17 javadocs] for <code>java.lang.reflect.AccessibleObject.setAccessible(boolean)</code></ref>
 * Runtime reflection loses the benefit of compile-time type checks, which allows dangerous operations such as trying to set a field's value to an incompatible type.
 * The use of reflection does not allow a class to extend a non-visible class.
@@ Line 101: / Line 101: @@
 The class name is the fully qualified name of the class, using <code>.</code> (dots) to separate between (sub)packages and classes (for example, <code>java.lang.Object</code>).
-For methods, the method descriptor<ref>''[https://docs.oracle.com/javase/specs/jvms/se16/html/jvms-4.html#jvms-4.3.3 Java Virtual Machine Specification, Java SE 16 Edition]'', 4.3.3. Method Descriptors </ref> of the method is included, which consists of the descriptors for each of the method's parameters and the method's return type. The method parameters descriptors can be absent if there are no parameters in the method, but the return type descriptor must be present.
+For methods, the method descriptor<ref>''[https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-4.html#jvms-4.3.3 Java Virtual Machine Specification, Java SE 17 Edition]'', 4.3.3. Method Descriptors </ref> of the method is included, which consists of the descriptors for each of the method's parameters and the method's return type. The method parameters descriptors can be absent if there are no parameters in the method, but the return type descriptor must be present.
 The following are the matching descriptors for each type as seen in the method declaration:

@@ Line 163: / Line 163: @@
 public net.minecraft.Util m_137477_(Ljava/lang/String;)Ljava/util/concurrent/ExecutorService; # makeExecutor
-# Makes public the 'leastMostToIntArray' method in SerializableUUID,
+# Makes public the 'leastMostToIntArray' method in UUIDUtil,
 # which accepts two longs and returns an int[]
-public net.minecraft.core.SerializableUUID m_123274_(JJ)[I # leastMostToIntArray
+public net.minecraft.core.UUIDUtil m_235872_(JJ)[I # leastMostToIntArray
 </syntaxhighlight>

@@ Line 4: / Line 4: @@
 == Background ==
-Java provides the mechanism of '''access level modifiers''' (or ''access modifiers''), to modify the ''visibility'' of a member with the modifier to other classes. This is commonly used to hide fields and methods from other classes, such as instance fields for [[:wikipedia:encapsulation|encapsulation]] or private methods which are part of the implementation of the class and should not be exposed to callers.
+Java provides the mechanism of '''access level modifiers''' (or ''access modifiers''), to modify the ''visibility'' of a member with the modifier to other classes. This is commonly used to hide fields and methods from other classes, such as instance fields for [[:wikipedia:Encapsulation (computer programming)|encapsulation]] or private methods which are part of the implementation of the class and not normally exposed to callers.
 A member can be declared with any of the modifier keywords <code>public</code>, <code>private</code>, <code>protected</code> to set the access level of the member, or none of the keywords, which defaults to a ''package-private'' access level.

@@ Line 13: / Line 13: @@
 ! Access modifier
 ! Within the same class
 ! Subclasses
 ! All other classes
 |-

@@ Line 128: / Line 128: @@
 | <code>[''I''</code> || <code>''int''[]</code> || one dimension of an array; this can be repeated, and must end with another descriptor other than an array
 |-
-| <code>L''java/lang/Object'';</code> || <code>java.lang.Object</code> || a reference type; the internal form of the class' binary name must be present (in the given example, the class referenced is <code>java.lang.Object</code>.
+| <code>L''java/lang/Object'';</code> || <code>java.lang.Object</code> || a reference type; the internal form of the class' binary name must be present (in the given example, the class referenced is <code>java.lang.Object</code>).
 Note that inner classes are separated using the <code>$</code> (dollar sign) character, such as <code>java/lang/System$Logger</code>.
 |-

@@ Line 139: / Line 139: @@
 To use wildcard access transformers:
-* for all methods within a class: <code>''<modifier>'' ''<class name>'' '''*'''</code>
+* for all methods within a class: <code>''<modifier>'' ''<class name>'' '''*()'''</code>
-* for all fields within a class: <code>''<modifier>'' ''<class name>'' '''*()'''</code>
+* for all fields within a class: <code>''<modifier>'' ''<class name>'' '''*'''</code>
 '''Modders should avoid using this in live code.''' Access transformers should always have the fewest and narrowest targets possible, and wildcard ATs violate this convention. Use of wildcard ATs may cause problems with both the ForgeGradle setup process. Wildcard ATs may be removed in a future update of the access transformer specification.

@@ Line 133: / Line 133: @@
 | <code>V</code> || <code>void</code> || a void or no-value return type; only available for the return type of a method descriptor
 |}
 == Examples ==

@@ Line 137: / Line 137: @@
 The following are some examples of access transformer declarations:
-<syntaxhighlight lang="java">
+<syntaxhighlight>
 # Makes public the ScreenConstructor class in MenuScreens
 public net.minecraft.client.gui.screens.MenuScreens$ScreenConstructor