Package org.apache.openjpa.enhance

Class PCEnhancer

  • public class PCEnhancer
extends java.lang.Object
    Bytecode enhancer used to enhance persistent classes from metadata. The enhancer must be invoked on all persistence-capable and persistence aware classes.
    Author:
    Abe White, Mark Struberg

    • Constructor Detail

      • PCEnhancer

        public PCEnhancer​(OpenJPAConfiguration conf,
                  java.lang.Class<?> type)
        Constructor. Supply configuration and type to enhance. This will look up the metadata for type from conf's repository.

      • PCEnhancer

        public PCEnhancer​(OpenJPAConfiguration conf,
                  ClassMetaData meta)
        Constructor. Supply configuration and type to enhance. This will look up the metadata for meta by converting back to a class and then loading from conf's repository.

      • PCEnhancer

        public PCEnhancer​(OpenJPAConfiguration conf,
                  ClassNodeTracker type,
                  MetaDataRepository repos,
                  java.lang.ClassLoader loader)
        Constructor. Supply configuration.
        Parameters:
        type - the bytecode representation fo the type to enhance; this can be created from any stream or file
        repos - a metadata repository to use for metadata access, or null to create a new reporitory; the repository from the given configuration isn't used by default because the configuration might be an implementation-specific subclass whose metadata required more than just base metadata files
        loader - the environment classloader to use for loading classes and resources.

      • PCEnhancer

        public PCEnhancer​(MetaDataRepository repos,
                  ClassNodeTracker type,
                  ClassMetaData meta)
        Constructor. Supply repository. The repository's configuration will be used, and the metadata passed in will be used as-is without doing any additional lookups. This is useful when running the enhancer during metadata load.
        Parameters:
        repos - a metadata repository to use for metadata access, or null to create a new reporitory; the repository from the given configuration isn't used by default because the configuration might be an implementation-specific subclass whose metadata required more than just base metadata files
        type - the bytecode representation fo the type to enhance; this can be created from any stream or file
        meta - the metadata to use for processing this type.
        Since:
        1.1.0

    • Method Detail

      • isPCSubclassName

        public static boolean isPCSubclassName​(java.lang.String className)
        Whether className is the name for a dynamically-created persistence-capable subclass.
        Since:
        1.1.0

      • toManagedTypeName

        public static java.lang.String toManagedTypeName​(java.lang.String className)
        If className is a dynamically-created persistence-capable subclass name, returns the name of the class that it subclasses. Otherwise, returns className.
        Since:
        1.1.0

      • getPCBytecode

        public ClassNodeTracker getPCBytecode()
        Return the bytecode representation of the persistence-capable class being manipulated.

      • getManagedTypeBytecode

        public ClassNodeTracker getManagedTypeBytecode()
        Return the bytecode representation of the managed class being manipulated. This is usually the same as getPCBytecode(), except when running the enhancer to redefine and subclass existing persistent types.

      • getMetaData

        public ClassMetaData getMetaData()
        Return the metadata for the class being manipulated, or null if not a persistent type.

      • getAddDefaultConstructor

        public boolean getAddDefaultConstructor()
        A boolean indicating whether the enhancer should add a no-args constructor if one is not already present in the class. OpenJPA requires that a no-arg constructor (whether created by the compiler or by the user) be present in a PC.

      • setAddDefaultConstructor

        public void setAddDefaultConstructor​(boolean addDefaultConstructor)
        A boolean indicating whether the enhancer should add a no-args constructor if one is not already present in the class. OpenJPA requires that a no-arg constructor (whether created by the compiler or by the user) be present in a PC.

      • getRedefine

        public boolean getRedefine()
        Whether the enhancer should mutate its arguments, or just run validation and optional subclassing logic on them. Usually used in conjunction with setCreateSubclass(true).
        Since:
        1.0.0

      • setRedefine

        public void setRedefine​(boolean redefine)
        Whether the enhancer should mutate its arguments, or just run validation and optional subclassing logic on them. Usually used in conjunction with setCreateSubclass(true).
        Since:
        1.0.0

      • isAlreadyRedefined

        public boolean isAlreadyRedefined()
        Whether the type that this instance is enhancing has already been redefined.
        Since:
        1.0.0

      • isAlreadySubclassed

        public boolean isAlreadySubclassed()
        Whether the type that this instance is enhancing has already been subclassed in this instance's environment classloader.
        Since:
        1.0.0

      • getCreateSubclass

        public boolean getCreateSubclass()
        Whether the enhancer should make its arguments persistence-capable, or generate a persistence-capable subclass.
        Since:
        1.0.0

      • setCreateSubclass

        public void setCreateSubclass​(boolean subclass)
        Whether the enhancer should make its arguments persistence-capable, or generate a persistence-capable subclass.
        Since:
        1.0.0

      • getEnforcePropertyRestrictions

        public boolean getEnforcePropertyRestrictions()
        Whether to fail if the persistent type uses property access and bytecode analysis shows that it may be violating OpenJPA's property access restrictions.

      • setEnforcePropertyRestrictions

        public void setEnforcePropertyRestrictions​(boolean fail)
        Whether to fail if the persistent type uses property access and bytecode analysis shows that it may be violating OpenJPA's property access restrictions.

      • getDirectory

        public java.io.File getDirectory()
        The base build directory to generate code to. The proper package structure will be created beneath this directory. Defaults to overwriting the existing class file if null.

      • setDirectory

        public void setDirectory​(java.io.File dir)
        The base build directory to generate code to. The proper package structure will be creaed beneath this directory. Defaults to overwriting the existing class file if null.

      • setBytecodeWriter

        public void setBytecodeWriter​(BytecodeWriter writer)
        Set the BytecodeWriter to write the bytecode to or null if none.

      • run

        public int run()
        Perform bytecode enhancements.
        Returns:
        ENHANCE_* constant

      • record

        public void record()
            throws java.io.IOException
        Write the generated bytecode.
        Throws:
        java.io.IOException

      • getType

        public java.lang.Class getType​(ClassMetaData meta)
        Return the concrete type for the given class, i.e. impl for managed interfaces

      • main

        public static void main​(java.lang.String[] args)
        Usage: java org.apache.openjpa.enhance.PCEnhancer [option]* <class name | .java file | .class file | .jdo file>+ Where the following options are recognized.
        • -properties/-p <properties file>: The path to a OpenJPA properties file containing information as outlined in Configuration; optional.
        • -<property name> <property value>: All bean properties of the standard OpenJPA OpenJPAConfiguration can be set by using their names and supplying a value; for example:
        • -directory/-d <build directory>: The path to the base directory where enhanced classes are stored. By default, the enhancer overwrites the original .class file with the enhanced version. Use this option to store the generated .class file in another directory. The package structure will be created beneath the given directory.
        • -addDefaultConstructor/-adc [true/t | false/f]: Whether to add a default constructor to persistent classes missing one, as opposed to throwing an exception. Defaults to true.
        • -tmpClassLoader/-tcl [true/t | false/f]: Whether to load the pre-enhanced classes using a temporary class loader. Defaults to true. Set this to false when attempting to debug class loading errors.
        • -enforcePropertyRestrictions/-epr [true/t | false/f]: Whether to throw an exception if a PROPERTY access entity appears to be violating standard property restrictions. Defaults to false.
        Each additional argument can be either the full class name of the type to enhance, the path to the .java file for the type, the path to the .class file for the type, or the path to a .jdo file listing one or more types to enhance. If the type being enhanced has metadata, it will be enhanced as a persistence capable class. If not, it will be considered a persistence aware class, and all access to fields of persistence capable classes will be replaced by the appropriate get/set method. If the type explicitly declares the persistence-capable interface, it will not be enhanced. Thus, it is safe to invoke the enhancer on classes that are already enhanced.

      • run

        public static boolean run​(java.lang.String[] args,
                          Options opts)
        Run the tool. Returns false if invalid options given. Runs against all the persistence units defined in the resource to parse.

      • run

        public static boolean run​(OpenJPAConfiguration conf,
                          java.lang.String[] args,
                          Options opts)
                   throws java.io.IOException
        Run the tool. Returns false if invalid options given.
        Throws:
        java.io.IOException

      • checkEnhancementLevel

        public static boolean checkEnhancementLevel​(java.lang.Class<?> cls,
                                            Log log)
        This static public worker method detects and logs any Entities that may have been enhanced at build time by a version of the enhancer that is older than the current version.
        Parameters:
        cls - - A non-null Class implementing org.apache.openjpa.enhance.PersistenceCapable.
        log - - A non-null org.apache.openjpa.lib.log.Log.
        Returns:
        true if the provided Class is down level from the current PCEnhancer.ENHANCER_VERSION. False otherwise.