Package groovy.lang

Class GroovyClassLoader

java.lang.Object
java.lang.ClassLoader
java.security.SecureClassLoader
java.net.URLClassLoader
groovy.lang.GroovyClassLoader
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
GroovyClassLoader.InnerLoader
public class GroovyClassLoader extends URLClassLoader
A ClassLoader which can load Groovy classes. The loaded classes are cached, classes from other classloaders should not be cached. To be able to load a script that was asked for earlier but was created later it is essential not to keep anything like a "class not found" information for that class name. This includes possible parent loaders. Classes that are not cached are always reloaded.

  • Field Details

    • classCache

      protected final EvictableCache<String,Class> classCache
      This cache contains the loaded classes or PARSING, if the class is currently parsed.

    • sourceCache

      protected final StampedCommonCache<String,Class> sourceCache
      This cache contains mappings of file name to class. It is used to bypass compilation.

  • Constructor Details

    • GroovyClassLoader

      public GroovyClassLoader()
      Creates a GroovyClassLoader using the current Thread's context ClassLoader as parent.

    • GroovyClassLoader

      public GroovyClassLoader(ClassLoader parent)
      Creates a GroovyClassLoader using the given ClassLoader as parent.

    • GroovyClassLoader

      public GroovyClassLoader(GroovyClassLoader parent)
      Creates a GroovyClassLoader using the given GroovyClassLoader as parent. The new loader will get the parent's CompilerConfiguration.

    • GroovyClassLoader

      public GroovyClassLoader(ClassLoader parent, CompilerConfiguration config)
      Creates a GroovyClassLoader using the given ClassLoader as parent.

    • GroovyClassLoader

      public GroovyClassLoader(ClassLoader parent, CompilerConfiguration config, boolean useConfigurationClasspath)
      Creates a GroovyClassLoader.
      Parameters:
      parent - the parent class loader
      config - the compiler configuration
      useConfigurationClasspath - determines if the configurations classpath should be added

  • Method Details

    • setResourceLoader

      public void setResourceLoader(GroovyResourceLoader resourceLoader)

    • getResourceLoader

      public GroovyResourceLoader getResourceLoader()

    • defineClass

      public Class defineClass(String name, byte[] bytes) throws ClassFormatError
      Converts an array of bytes into an instance of Class. Before the class can be used it must be resolved.
      Throws:
      ClassFormatError

    • defineClass

      public Class defineClass(ClassNode classNode, String file, String newCodeBase)
      Compiles the given ClassNode returning the resulting Class.

      WARNING: compilation is not synchronized

    • hasCompatibleConfiguration

      public boolean hasCompatibleConfiguration(CompilerConfiguration config)
      Checks if this class loader has compatible CompilerConfiguration with the provided one.
      Parameters:
      config - the compiler configuration to test for compatibility
      Returns:
      true if the provided config is exactly the same instance of CompilerConfiguration as this loader has

    • parseClass

      public Class parseClass(File file) throws CompilationFailedException, IOException
      Parses the given file into a Java class capable of being run
      Parameters:
      file - the file name to parse
      Returns:
      the main class defined in the given script
      Throws:
      CompilationFailedException
      IOException

    • parseClass

      public Class parseClass(String text, String fileName) throws CompilationFailedException
      Parses the given text into a Java class capable of being run
      Parameters:
      text - the text of the script/class to parse
      fileName - the file name to use as the name of the class
      Returns:
      the main class defined in the given script
      Throws:
      CompilationFailedException

    • parseClass

      public Class parseClass(String text) throws CompilationFailedException
      Parses the given text into a Java class capable of being run
      Parameters:
      text - the text of the script/class to parse
      Returns:
      the main class defined in the given script
      Throws:
      CompilationFailedException

    • parseClass

      public Class parseClass(Reader reader, String fileName) throws CompilationFailedException
      Throws:
      CompilationFailedException

    • parseClass

      public Class parseClass(GroovyCodeSource codeSource) throws CompilationFailedException
      Throws:
      CompilationFailedException

    • parseClass

      public Class parseClass(GroovyCodeSource codeSource, boolean shouldCacheSource) throws CompilationFailedException
      Parses the given code source into a Java class. If there is a class file for the given code source, then no parsing is done, instead the cached class is returned.
      Parameters:
      shouldCacheSource - if true then the generated class will be stored in the source cache
      Returns:
      the main class defined in the given script
      Throws:
      CompilationFailedException

    • generateScriptName

      public String generateScriptName()

    • getClassPath

      protected String[] getClassPath()
      gets the currently used classpath.
      Returns:
      a String[] containing the file information of the urls
      See Also:

    • getPermissions

      protected PermissionCollection getPermissions(CodeSource codeSource)
      Overrides:
      getPermissions in class URLClassLoader

    • createCompilationUnit

      protected CompilationUnit createCompilationUnit(CompilerConfiguration config, CodeSource source)
      creates a new CompilationUnit. If you want to add additional phase operations to the CompilationUnit (for example to inject additional methods, variables, fields), then you should overwrite this method.
      Parameters:
      config - the compiler configuration, usually the same as for this class loader
      source - the source containing the initial file to compile, more files may follow during compilation
      Returns:
      the CompilationUnit

    • createCollector

      protected GroovyClassLoader.ClassCollector createCollector(CompilationUnit unit, SourceUnit su)
      creates a ClassCollector for a new compilation.
      Parameters:
      unit - the compilationUnit
      su - the SourceUnit
      Returns:
      the ClassCollector

    • getClassCacheEntry

      protected Class getClassCacheEntry(String name)
      gets a class from the class cache. This cache contains only classes loaded through this class loader or an InnerLoader instance. If no class is stored for a specific name, then the method should return null.
      Parameters:
      name - of the class
      Returns:
      the class stored for the given name
      See Also:

    • setClassCacheEntry

      protected void setClassCacheEntry(Class cls)
      sets an entry in the class cache.
      Parameters:
      cls - the class
      See Also:

    • removeClassCacheEntry

      protected void removeClassCacheEntry(String name)
      removes a class from the class cache.
      Parameters:
      name - of the class
      See Also:

    • addURL

      public void addURL(URL url)
      adds a URL to the classloader.
      Overrides:
      addURL in class URLClassLoader
      Parameters:
      url - the new classpath element

    • isRecompilable

      protected boolean isRecompilable(Class cls)
      Indicates if a class is recompilable. Recompilable means, that the classloader will try to locate a groovy source file for this class and then compile it again, adding the resulting class as entry to the cache. Giving null as class is like a recompilation, so the method should always return true here. Only classes that are implementing GroovyObject are compilable and only if the timestamp in the class is lower than Long.MAX_VALUE.

      NOTE: First the parent loaders will be asked and only if they don't return a class the recompilation will happen. Recompilation also only happen if the source file is newer.

      Parameters:
      cls - the class to be tested. If null the method should return true
      Returns:
      true if the class should be compiled again
      See Also:

    • setShouldRecompile

      public void setShouldRecompile(Boolean mode)
      sets if the recompilation should be enabled. There are 3 possible values for this. Any value different from null overrides the value from the compiler configuration. true means to recompile if needed false means to never recompile.
      Parameters:
      mode - the recompilation mode
      See Also:

    • isShouldRecompile

      public Boolean isShouldRecompile()
      gets the currently set recompilation mode. null means, the compiler configuration is used. False means no recompilation and true means that recompilation will be done if needed.
      Returns:
      the recompilation mode

    • loadClass

      public Class<?> loadClass(String name) throws ClassNotFoundException
      Overrides:
      loadClass in class ClassLoader
      Throws:
      ClassNotFoundException
      See Also:

    • loadClass

      protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException, CompilationFailedException
      Implemented here to check package access prior to returning an already-loaded class.
      Overrides:
      loadClass in class ClassLoader
      Throws:
      ClassNotFoundException - if class could not be found
      CompilationFailedException - if compilation of script failed

    • loadClass

      public Class loadClass(String name, boolean lookupScriptFiles, boolean preferClassOverScript) throws ClassNotFoundException, CompilationFailedException
      Loads a class from a file or a parent loader. This method delegates to: 
       loadClass(name, lookupScriptFiles, preferClassOverScript, false);
      Throws:
      ClassNotFoundException - if class could not be found
      CompilationFailedException - if compilation of script failed

    • loadClass

      public Class loadClass(String name, boolean lookupScriptFiles, boolean preferClassOverScript, boolean resolve) throws ClassNotFoundException, CompilationFailedException
      Loads a class from a file or a parent loader.
      Parameters:
      name - of the class to be loaded
      lookupScriptFiles - if false no lookup at files is done at all
      preferClassOverScript - if true the file lookup is only done if there is no class
      resolve - see ClassLoader.loadClass(java.lang.String, boolean)
      Returns:
      the class found or the class created from a file lookup
      Throws:
      ClassNotFoundException - if class could not be found
      CompilationFailedException - if compilation of script failed

    • recompile

      protected Class recompile(URL source, String className, Class oldClass) throws CompilationFailedException, IOException
      (Re)Compiles the given source. This method starts the compilation of a given source, if the source has changed since the class was created. For this isSourceNewer is called.
      Parameters:
      source - the source pointer for the compilation
      className - the name of the class to be generated
      oldClass - a possible former class
      Returns:
      the old class if the source wasn't new enough, the new class else
      Throws:
      CompilationFailedException - if the compilation failed
      IOException - if the source is not readable
      See Also:

    • getTimeStamp

      protected long getTimeStamp(Class cls)
      Gets the time stamp of a given class. For groovy generated classes this usually means to return the value of the static field __timeStamp. If the parameter doesn't have such a field, then Long.MAX_VALUE is returned
      Parameters:
      cls - the class
      Returns:
      the time stamp

    • isSourceNewer

      protected boolean isSourceNewer(URL source, Class cls) throws IOException
      Decides if the given source is newer than a class.
      Parameters:
      source - the source we may want to compile
      cls - the former class
      Returns:
      true if the source is newer, false else
      Throws:
      IOException - if it is not possible to open a connection for the given source
      See Also:

    • addClasspath

      public void addClasspath(String path)
      adds a classpath to this classloader.
      Parameters:
      path - is a jar file or a directory.
      See Also:

    • getLoadedClasses

      public Class[] getLoadedClasses()

      Returns all Groovy classes loaded by this class loader.

      Returns:
      all classes loaded by this class loader

    • clearCache

      public void clearCache()
      Removes all classes from the class cache.

      In addition to internal caches this method also clears any previously set MetaClass information for the given set of classes being removed.

      See Also:

    • close

      public void close() throws IOException
      Closes this GroovyClassLoader and clears any caches it maintains.

      No use should be made of this instance after this method is invoked. Any classes that are already loaded are still accessible.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class URLClassLoader
      Throws:
      IOException
      Since:
      2.5.0
      See Also:

    • genEncodingString

      public String genEncodingString(CharSequence chars)
      Generates an encoded string based on the specified characters and the defined encoding algorithm. Supported algorithms currently are "md5" and sha256". An exception is throw for an unknown algorithm or if the JVM doesn't support the algorithm.
      Parameters:
      chars - The characters to encode.
      Returns:
      The encoded string.