Module org.jooq
Package org.jooq.tools.reflect

Class Reflect

java.lang.Object
org.jooq.tools.reflect.Reflect
public class Reflect extends Object
A wrapper for an Object or Class upon which reflective calls can be made.

An example of using Reflect is 


 // Static import all reflection methods to decrease verbosity
 import static org.joor.Reflect.*;

 // Wrap an Object / Class / class name with the on() method:
 on("java.lang.String")
 // Invoke constructors using the create() method:
 .create("Hello World")
 // Invoke methods using the call() method:
 .call("toString")
 // Retrieve the wrapped object
Author:
Lukas Eder, Irek Matysiewicz, Thomas Darimont

  • Method Details

    • compile

      public static Reflect compile(String name, String content) throws ReflectException
      Compile a class at runtime and reflect on it.

      For example: 

      
 Supplier<String> supplier = Reflect.compile("org.joor.Test", """
   package org.joor;
   class Test implements java.util.function.Supplier<String> {
     public String get() {
       return "Hello World!";
     }
   }
   """).create().get();
      Parameters:
      name - The qualified class name
      content - The source code for the class
      Returns:
      A wrapped Class
      Throws:
      ReflectException - if anything went wrong compiling the class.

    • compile

      public static Reflect compile(String name, String content, CompileOptions options) throws ReflectException
      Compile a class at runtime and reflect on it.

      For example: 

      
 Supplier<String> supplier = Reflect.compile("org.joor.Test", """
   package org.joor;
   class Test implements java.util.function.Supplier<String> {
     public String get() {
       return "Hello World!";
     }
   }
   """).create().get();
      Parameters:
      name - The qualified class name
      content - The source code for the class
      options - compiler options
      Returns:
      A wrapped Class
      Throws:
      ReflectException - if anything went wrong compiling the class.

    • process

      public static void process(String name, String content) throws ReflectException
      Annotation-process a class at runtime.

      This works like compile(String, String), but adds the -proc:only CompileOptions and thus does not produce any compilation output.

      For example: 

      
 Supplier<String> supplier = Reflect.compile("org.joor.Test", """
   package org.joor;
   @MyAnnotation
   class Test implements java.util.function.Supplier<String> {
     public String get() {
       return "Hello World!";
     }
   }
   """).create().get();
      Parameters:
      name - The qualified class name
      content - The source code for the class
      Throws:
      ReflectException - if anything went wrong compiling the class.

    • process

      public static void process(String name, String content, CompileOptions options) throws ReflectException
      Annotation-process a class at runtime.

      This works like compile(String, String), but adds the -proc:only CompileOptions and thus does not produce any compilation output.

      For example: 

      
 Supplier<String> supplier = Reflect.compile("org.joor.Test", """
   package org.joor;
   @MyAnnotation
   class Test implements java.util.function.Supplier<String> {
     public String get() {
       return "Hello World!";
     }
   }
   """).create().get();
      Parameters:
      name - The qualified class name
      content - The source code for the class
      options - compiler options
      Throws:
      ReflectException - if anything went wrong compiling the class.

    • on

      @Deprecated public static Reflect on(String name) throws ReflectException
      Deprecated.
      [#78] 0.9.11, use onClass(String) instead.
      Wrap a class name.

      This is the same as calling on(Class.forName(name))

      Parameters:
      name - A fully qualified class name
      Returns:
      A wrapped class object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • on

      @Deprecated public static Reflect on(String name, ClassLoader classLoader) throws ReflectException
      Deprecated.
      [#78] 0.9.11, use onClass(String, ClassLoader) instead.
      Wrap a class name, loading it via a given class loader.

      This is the same as calling on(Class.forName(name, classLoader))

      Parameters:
      name - A fully qualified class name.
      classLoader - The class loader in whose context the class should be loaded.
      Returns:
      A wrapped class object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • on

      @Deprecated public static Reflect on(Class<?> clazz)
      Deprecated.
      [#78] 0.9.11, use onClass(Class) instead.
      Wrap a class.

      Use this when you want to access static fields and methods on a Class object, or as a basis for constructing objects of that class using create(Object...)

      Parameters:
      clazz - The class to be wrapped
      Returns:
      A wrapped class object, to be used for further reflection.

    • onClass

      public static Reflect onClass(String name) throws ReflectException
      Wrap a class name.

      This is the same as calling onClass(Class.forName(name))

      Parameters:
      name - A fully qualified class name
      Returns:
      A wrapped class object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • onClass

      public static Reflect onClass(String name, ClassLoader classLoader) throws ReflectException
      Wrap a class name, loading it via a given class loader.

      This is the same as calling onClass(Class.forName(name, classLoader))

      Parameters:
      name - A fully qualified class name.
      classLoader - The class loader in whose context the class should be loaded.
      Returns:
      A wrapped class object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • onClass

      public static Reflect onClass(Class<?> clazz)
      Wrap a class.

      Use this when you want to access static fields and methods on a Class object, or as a basis for constructing objects of that class using create(Object...)

      Parameters:
      clazz - The class to be wrapped
      Returns:
      A wrapped class object, to be used for further reflection.

    • on

      public static Reflect on(Object object)
      Wrap an object.

      Use this when you want to access instance fields and methods on any Object

      Parameters:
      object - The object to be wrapped
      Returns:
      A wrapped object, to be used for further reflection.

    • initValue

      public static <T> T initValue(Class<T> type)
      Get the initialisation or default value for any given type.

      This returns:

      • null for reference types (including wrapper types)
      • 0 for numeric primitive types (including char)
      • false for the boolean primitive type.

    • accessible

      public static <T extends AccessibleObject> T accessible(T accessible)
      Conveniently render an AccessibleObject accessible.

      To prevent SecurityException, this is only done if the argument object and its declaring class are non-public.

      Parameters:
      accessible - The object to render accessible
      Returns:
      The argument object rendered accessible

    • get

      public <T> T get()
      Get the wrapped object
      Type Parameters:
      T - A convenience generic parameter for automatic unsafe casting

    • set

      public Reflect set(String name, Object value) throws ReflectException
      Set a field value.

      This is roughly equivalent to Field.set(Object, Object). If the wrapped object is a Class, then this will set a value to a static member field. If the wrapped object is any other Object, then this will set a value to an instance member field.

      This method is also capable of setting the value of (static) final fields. This may be convenient in situations where no SecurityManager is expected to prevent this, but do note that (especially static) final fields may already have been inlined by the javac and/or JIT and relevant code deleted from the runtime verison of your program, so setting these fields might not have any effect on your execution.

      For restrictions of usage regarding setting values on final fields check: http://stackoverflow.com/questions/3301635/change-private-static-final-field-using-java-reflection ... and http://pveentjer.blogspot.co.at/2017/01/final-static-boolean-jit.html

      Parameters:
      name - The field name
      value - The new field value
      Returns:
      The same wrapped object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.

    • get

      public <T> T get(String name) throws ReflectException
      Get a field value.

      This is roughly equivalent to Field.get(Object). If the wrapped object is a Class, then this will get a value from a static member field. If the wrapped object is any other Object, then this will get a value from an instance member field.

      If you want to "navigate" to a wrapped version of the field, use field(String) instead.

      Parameters:
      name - The field name
      Returns:
      The field value
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • field

      public Reflect field(String name) throws ReflectException
      Get a wrapped field.

      This is roughly equivalent to Field.get(Object). If the wrapped object is a Class, then this will wrap a static member field. If the wrapped object is any other Object, then this wrap an instance member field.

      Parameters:
      name - The field name
      Returns:
      The wrapped field
      Throws:
      ReflectException - If any reflection exception occurred.

    • fields

      public Map<String,Reflect> fields()
      Get a Map containing field names and wrapped values for the fields' values.

      If the wrapped object is a Class, then this will return static fields. If the wrapped object is any other Object, then this will return instance fields.

      These two calls are equivalent 

      
 on(object).field("myField");
 on(object).fields().get("myField");
      Returns:
      A map containing field names and wrapped values.

    • call

      public Reflect call(String name) throws ReflectException
      Call a method by its name.

      This is a convenience method for calling call(name, new Object[0])

      Parameters:
      name - The method name
      Returns:
      The wrapped method result or the same wrapped object if the method returns void, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • call

      public Reflect call(String name, Object... args) throws ReflectException
      Call a method by its name.

      This is roughly equivalent to Method.invoke(Object, Object...). If the wrapped object is a Class, then this will invoke a static method. If the wrapped object is any other Object, then this will invoke an instance method.

      Just like Method.invoke(Object, Object...), this will try to wrap primitive types or unwrap primitive type wrappers if applicable. If several methods are applicable, by that rule, the first one encountered is called. i.e. when calling 

      
 on(...).call("method", 1, 1);
      The first of the following methods will be called: 
      
 public void method(int param1, Integer param2);
 public void method(Integer param1, int param2);
 public void method(Number param1, Number param2);
 public void method(Number param1, Object param2);
 public void method(int param1, Object param2);

      The best matching method is searched for with the following strategy:

      1. public method with exact signature match in class hierarchy
      2. non-public method with exact signature match on declaring class
      3. public method with similar signature in class hierarchy
      4. non-public method with similar signature on declaring class
      Parameters:
      name - The method name
      args - The method arguments
      Returns:
      The wrapped method result or the same wrapped object if the method returns void, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.

    • create

      public Reflect create() throws ReflectException
      Call a constructor.

      This is a convenience method for calling create(new Object[0])

      Returns:
      The wrapped new object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.
      See Also:

    • create

      public Reflect create(Object... args) throws ReflectException
      Call a constructor.

      This is roughly equivalent to Constructor.newInstance(Object...). If the wrapped object is a Class, then this will create a new object of that class. If the wrapped object is any other Object, then this will create a new object of the same type.

      Just like Constructor.newInstance(Object...), this will try to wrap primitive types or unwrap primitive type wrappers if applicable. If several constructors are applicable, by that rule, the first one encountered is called. i.e. when calling 

      
 on(C.class).create(1, 1);
      The first of the following constructors will be applied: 
      
 public C(int param1, Integer param2);
 public C(Integer param1, int param2);
 public C(Number param1, Number param2);
 public C(Number param1, Object param2);
 public C(int param1, Object param2);
      Parameters:
      args - The constructor arguments
      Returns:
      The wrapped new object, to be used for further reflection.
      Throws:
      ReflectException - If any reflection exception occurred.

    • as

      public <P> P as(Class<P> proxyType)
      Create a proxy for the wrapped object allowing to typesafely invoke methods on it using a custom interface.
      Parameters:
      proxyType - The interface type that is implemented by the proxy
      Returns:
      A proxy for the wrapped object

    • as

      public <P> P as(Class<P> proxyType, Class<?>... additionalInterfaces)
      Create a proxy for the wrapped object allowing to typesafely invoke methods on it using a custom interface.
      Parameters:
      proxyType - The interface type that is implemented by the proxy
      additionalInterfaces - Additional interfaces that are implemented by the proxy
      Returns:
      A proxy for the wrapped object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • type

      public Class<?> type()
      Get the type of the wrapped object.
      See Also:

    • wrapper

      public static <T> Class<T> wrapper(Class<T> type)
      Get a wrapper type for a primitive type, or the argument type itself, if it is not a primitive type.