skywalking-java/docs
Gong Dewei 267aba8fad
Improve bytebuddy class enhance for retransform classes (#561)
* SWAuxiliaryTypeNamingStrategy
Auxiliary type name pattern: <origin_class_name>$<name_trait>$auxiliary$<auxiliary_type_instance_hash>

* DelegateNamingResolver
Interceptor delegate field name pattern: <name_trait>$delegate$<class_name_hash>$<plugin_define_hash>$<intercept_point_hash>

* SWMethodNameTransformer
Renamed origin method pattern: <name_trait>$original$<method_name>$<method_description_hash>

* SWImplementationContextFactory
Method cache value field pattern: cachedValue$<name_trait>$<origin_class_name_hash>$<field_value_hash>
Accessor method name pattern:  <renamed_origin_method>$accessor$<name_trait>$<origin_class_name_hash>

Here is an example of manipulated enhanced class with new naming policies of auxiliary classes, fields, and methods

```java
 import sample.mybatis.controller.HotelController$sw$auxiliary$19cja42;
 import sample.mybatis.controller.HotelController$sw$auxiliary$p257su0;
 import sample.mybatis.domain.Hotel;
 import sample.mybatis.service.HotelService;

 @RequestMapping(value={"/hotel"})
 @RestController
 public class HotelController
 implements EnhancedInstance {
     @Autowired
     @Lazy
     private HotelService hotelService;
     private volatile Object _$EnhancedClassField_ws;

     // Interceptor delegate fields
     public static volatile /* synthetic */ InstMethodsInter sw$delegate$td03673$ain2do0$8im5jm1;
     public static volatile /* synthetic */ InstMethodsInter sw$delegate$td03673$ain2do0$edkmf61;
     public static volatile /* synthetic */ ConstructorInter sw$delegate$td03673$ain2do0$qs9unv1;
     public static volatile /* synthetic */ InstMethodsInter sw$delegate$td03673$fl4lnk1$m3ia3a2;
     public static volatile /* synthetic */ InstMethodsInter sw$delegate$td03673$fl4lnk1$sufrvp1;
     public static volatile /* synthetic */ ConstructorInter sw$delegate$td03673$fl4lnk1$cteu7s1;

     // Origin method cache value field
     private static final /* synthetic */ Method cachedValue$sw$td03673$g5sobj1;

     public HotelController() {
         this(null);
         sw$delegate$td03673$ain2do0$qs9unv1.intercept(this, new Object[0]);
     }

     private /* synthetic */ HotelController(sw.auxiliary.p257su0 p257su02) {
     }

     @GetMapping(value={"city/{cityId}"})
     public Hotel selectByCityId(@PathVariable(value="cityId") int n) {
         // call interceptor with auxiliary type and parameters and origin method object
         return (Hotel)sw$delegate$td03673$ain2do0$8im5jm1.intercept(this, new Object[]{n}, new HotelController$sw$auxiliary$19cja42(this, n), cachedValue$sw$td03673$g5sobj1);
     }

     // Renamed origin method
     private /* synthetic */ Hotel sw$origin$selectByCityId$a8458p3(int cityId) {
/*22*/         return this.hotelService.selectByCityId(cityId);
     }

     // Accessor of renamed origin method, calling from auxiliary type
     final /* synthetic */ Hotel sw$origin$selectByCityId$a8458p3$accessor$sw$td03673(int n) {
         // Calling renamed origin method
         return this.sw$origin$selectByCityId$a8458p3(n);
     }

     @Override
     public Object getSkyWalkingDynamicField() {
         return this._$EnhancedClassField_ws;
     }

     @Override
     public void setSkyWalkingDynamicField(Object object) {
         this._$EnhancedClassField_ws = object;
     }

     static {
         ClassLoader.getSystemClassLoader().loadClass("org.apache.skywalking.apm.dependencies.net.bytebuddy.dynamic.Nexus").getMethod("initialize", Class.class, Integer.TYPE).invoke(null, HotelController.class, -1072476370);
         // Method object
         cachedValue$sw$td03673$g5sobj1 = HotelController.class.getMethod("selectByCityId", Integer.TYPE);
     }
 }
```

Auxiliary type of Constructor : 
```java
class HotelController$sw$auxiliary$p257su0 {
}
```

Auxiliary type of  `selectByCityId` method: 
```java
class HotelController$sw$auxiliary$19cja42
implements Runnable,
Callable {
    private HotelController argument0;
    private int argument1;

    public Object call() throws Exception {
        return this.argument0.sw$origin$selectByCityId$a8458p3$accessor$sw$td03673(this.argument1);
    }

    @Override
    public void run() {
        this.argument0.sw$origin$selectByCityId$a8458p3$accessor$sw$td03673(this.argument1);
    }

    HotelController$sw$auxiliary$19cja42(HotelController hotelController, int n) {
        this.argument0 = hotelController;
        this.argument1 = n;
    }
}
```
2023-06-24 20:50:10 +08:00
..
en Improve bytebuddy class enhance for retransform classes (#561) 2023-06-24 20:50:10 +08:00
README.md Update README.md (#308) 2022-09-13 19:13:24 +08:00
menu.yml Polish docs for preparing release. (#490) 2023-03-29 11:21:50 +08:00

README.md

SkyWalking Java Agent

This is the official documentation of SkyWalking Java agent. Welcome to the SkyWalking community!

The Java Agent for Apache SkyWalking, which provides the native tracing/metrics/logging/event abilities for Java projects.

In here, you could learn how to set up Java agent for the Java Runtime Envrionment services.