Package org.codehaus.commons.compiler.jdk

Class ClassBodyEvaluator

java.lang.Object
org.codehaus.commons.compiler.Cookable
org.codehaus.commons.compiler.jdk.SimpleCompiler
org.codehaus.commons.compiler.jdk.ClassBodyEvaluator
All Implemented Interfaces:
IClassBodyEvaluator, ICookable, ISimpleCompiler
Direct Known Subclasses:
ScriptEvaluator
public class ClassBodyEvaluator extends SimpleCompiler implements IClassBodyEvaluator
To set up a ClassBodyEvaluator object, proceed as described for IClassBodyEvaluator. Alternatively, a number of "convenience constructors" exist that execute the described steps instantly.

Notice that this implementation of IClassBodyEvaluator is prone to "Java injection", i.e. an application could get more than one class body compiled by passing a bogus input document.

Also notice that the parsing of leading IMPORT declarations is heuristic and has certain limitations; see parseImportDeclarations(Reader).

See Also:

  • Constructor Details

    • ClassBodyEvaluator

      public ClassBodyEvaluator()

  • Method Details

    • setClassName

      public void setClassName(String className)
      Description copied from interface: IClassBodyEvaluator
      Set the name of the generated class. Defaults to IClassBodyEvaluator.DEFAULT_CLASS_NAME. In most cases, there is no need to set this name, because the generated class is loaded into its own ClassLoader where its name cannot collide with classes generated by other evaluators.

      One reason to use this function is to have a class name in a non-default package, which can be relevant when types and members with DEFAULT accessibility are accessed.

      Specified by:
      setClassName in interface IClassBodyEvaluator

    • setDefaultImports

      public void setDefaultImports(String[] optionalDefaultImports)
      Description copied from interface: IClassBodyEvaluator
      "Default imports" add to the system import "java.lang", i.e. the evaluator may refer to classes imported by default imports without having to explicitly declare IMPORT statements.

      Notice that JDK 5 "static imports" are also supported, as shown in the following example.

      Example: 

           sc.setDefaultImports(new String[] {
         "java.util.Map",                          // Single type import
         "java.io.*",                              // Type-import-on-demand
         "static java.util.Collections.EMPTY_MAP", // Single static import
         "static java.util.Collections.*",         // Static-import-on-demand
     });
      Specified by:
      setDefaultImports in interface IClassBodyEvaluator

    • setExtendedClass

      public void setExtendedClass(Class optionalExtendedType)
      Description copied from interface: IClassBodyEvaluator
      Set a particular superclass that the generated class will extend. If null is passed, the generated class will extend Object.

      The common reason to set a base class for an evaluator is that the generated class can directly access the base superclass's (non-private) members.

      Specified by:
      setExtendedClass in interface IClassBodyEvaluator

    • setExtendedType

      @Deprecated public void setExtendedType(Class optionalExtendedClass)
      Deprecated.
      Specified by:
      setExtendedType in interface IClassBodyEvaluator

    • setImplementedInterfaces

      public void setImplementedInterfaces(Class[] implementedTypes)
      Description copied from interface: IClassBodyEvaluator
      Set a particular set of interfaces that the generated class will implement.
      Specified by:
      setImplementedInterfaces in interface IClassBodyEvaluator

    • setImplementedTypes

      @Deprecated public void setImplementedTypes(Class[] implementedInterfaces)
      Deprecated.
      Specified by:
      setImplementedTypes in interface IClassBodyEvaluator

    • cook

      public void cook(String optionalFileName, Reader r) throws CompileException, IOException
      Description copied from interface: ICookable
      Reads, scans, parses and compiles Java tokens from the given Reader.
      Specified by:
      cook in interface ICookable
      Overrides:
      cook in class SimpleCompiler
      Parameters:
      optionalFileName - Used when reporting errors and warnings.
      Throws:
      CompileException
      IOException
      See Also:

    • cook

      protected void cook(String optionalFileName, String[] imports, Reader r) throws CompileException, IOException
      Parameters:
      imports - E.g. "java.io.*" or "static java.util.Arrays.asList"
      r - The class body to cook, without leading IMPORT declarations
      Throws:
      CompileException
      IOException

    • getClazz

      public Class<?> getClazz()
      Description copied from interface: IClassBodyEvaluator
      Returns the loaded Class.

      This method must only be called after exactly one of the ICookable.cook(String, java.io.Reader) methods was called.

      Specified by:
      getClazz in interface IClassBodyEvaluator
      Returns:
      The Class created by the preceding call to Cookable.cook(Reader)

    • parseImportDeclarations

      protected static String[] parseImportDeclarations(Reader r) throws IOException
      Heuristically parse IMPORT declarations at the beginning of the character stream produced by the given Reader. After this method returns, all characters up to and including that last IMPORT declaration have been read from the Reader.

      This method does not handle comments and string literals correctly, i.e. if a pattern that looks like an IMPORT declaration appears within a comment or a string literal, it will be taken as an IMPORT declaration.

      Parameters:
      r - A Reader that supports MARK, e.g. a BufferedReader
      Returns:
      The parsed imports, e.g. { "java.util.*", "static java.util.Map.Entry" }
      Throws:
      IOException

    • createInstance

      public Object createInstance(Reader reader) throws CompileException, IOException
      Description copied from interface: IClassBodyEvaluator
      Scans, parses and compiles a class body from the tokens delivered by the the given Reader, then creates and returns an instance of that class.
      Specified by:
      createInstance in interface IClassBodyEvaluator
      Parameters:
      reader - Source of class body tokens
      Returns:
      An object that extends the optionalExtendedType and implements the given implementedTypes
      Throws:
      CompileException
      IOException