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:

IClassBodyEvaluator

Field Summary

Fields inherited from interface org.codehaus.commons.compiler.IClassBodyEvaluator

DEFAULT_CLASS_NAME

Fields inherited from interface org.codehaus.commons.compiler.ICookable

BOOT_CLASS_LOADER, SYSTEM_PROPERTY_SOURCE_DEBUGGING_DIR, SYSTEM_PROPERTY_SOURCE_DEBUGGING_ENABLE

Constructor Summary

ClassBodyEvaluator()

Method Summary

void	cook(String optionalFileName, Reader r) Reads, scans, parses and compiles Java tokens from the given Reader.
protected void	cook(String optionalFileName, String[] imports, Reader r)
Object	createInstance(Reader reader) 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.
Class<?>	getClazz() Returns the loaded Class.
protected static String[]	parseImportDeclarations(Reader r) Heuristically parse IMPORT declarations at the beginning of the character stream produced by the given Reader.
void	setClassName(String className) Set the name of the generated class.
void	setDefaultImports(String[] optionalDefaultImports) "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.
void	setExtendedClass(Class optionalExtendedType) Set a particular superclass that the generated class will extend.
void	setExtendedType(Class optionalExtendedClass) Deprecated.
void	setImplementedInterfaces(Class[] implementedTypes) Set a particular set of interfaces that the generated class will implement.
void	setImplementedTypes(Class[] implementedInterfaces) Deprecated.

Methods inherited from class org.codehaus.commons.compiler.jdk.SimpleCompiler

assertCooked, assertNotCooked, getClassLoader, setCompileErrorHandler, setDebuggingInformation, setParentClassLoader, setParentClassLoader, setWarningHandler

Methods inherited from class org.codehaus.commons.compiler.Cookable

cook, cook, cook, cook, cook, cook, cook, cookFile, cookFile, cookFile, cookFile, readString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.codehaus.commons.compiler.ICookable

cook, cook, cook, cook, cook, cook, cook, cookFile, cookFile, cookFile, cookFile, setCompileErrorHandler, setDebuggingInformation, setParentClassLoader, setWarningHandler

Constructor Detail

ClassBodyEvaluator

public ClassBodyEvaluator()

Method Detail

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:

ICookable.cook(String, Reader)

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