public interface IClassBodyEvaluator extends ICookable
Class
object ready for use with
java.lang.reflect.
Example:
import java.util.*; static private int a = 1; private int b = 2; public void func(int c, int d) { return func2(c, d); } private static void func2(int e, int f) { return e * f; }
To set up an IClassBodyEvaluator
object, proceed as follows:
IClassBodyEvaluator
-implementing class.
IClassBodyEvaluator
by calling any of the following methods:
ICookable.cook(String, java.io.Reader)
methods to scan,
parse, compile and load the class body into the JVM.
createInstance(Reader)
methods can be
used.
The generated class may optionally extend/implement a given type; the returned instance can
safely be type-casted to that optionalBaseType
.
Example:
public interface Foo { int bar(int a, int b); } ...IClassBodyEvaluator
cbe =CompilerFactoryFactory
.getDefaultCompilerFactory
().newClassBodyEvaluator
(); Foo f = (Foo) ClassBodyEvaluator.createFastClassBodyEvaluator( new Scanner(null, new StringReader("public int bar(int a, int b) { return a + b; }")), Foo.class, // Base type to extend/implement (ClassLoader) null // Use current thread's context class loader ); System.out.println("1 + 2 = " + f.bar(1, 2));
Modifier and Type | Field and Description |
---|---|
static String |
DEFAULT_CLASS_NAME
Default name for the generated class.
|
BOOT_CLASS_LOADER, SYSTEM_PROPERTY_SOURCE_DEBUGGING_DIR, SYSTEM_PROPERTY_SOURCE_DEBUGGING_ENABLE
Modifier and Type | Method and Description |
---|---|
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 . |
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.
|
void |
setExtendedClass(Class optionalExtendedClass)
Set a particular superclass that the generated class will extend.
|
void |
setExtendedType(Class optionalExtendedClass)
Deprecated.
Use
setExtendedClass(Class) instead. |
void |
setImplementedInterfaces(Class[] implementedInterfaces)
Set a particular set of interfaces that the generated class will implement.
|
void |
setImplementedTypes(Class[] implementedInterfaces)
Deprecated.
Use
setImplementedInterfaces(Class[]) instead. |
cook, cook, cook, cook, cook, cook, cook, cook, cookFile, cookFile, cookFile, cookFile, setCompileErrorHandler, setDebuggingInformation, setParentClassLoader, setWarningHandler
static final String DEFAULT_CLASS_NAME
void setDefaultImports(String[] optionalDefaultImports)
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 });
void setClassName(String className)
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.
void setExtendedClass(Class optionalExtendedClass)
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.
@Deprecated void setExtendedType(Class optionalExtendedClass)
setExtendedClass(Class)
instead.void setImplementedInterfaces(Class[] implementedInterfaces)
@Deprecated void setImplementedTypes(Class[] implementedInterfaces)
setImplementedInterfaces(Class[])
instead.Class getClazz()
Class
.
This method must only be called after exactly one of the ICookable.cook(String,
java.io.Reader)
methods was called.
Object createInstance(Reader reader) throws CompileException, IOException
Reader
, then creates
and returns an instance of that class.reader
- Source of class body tokensoptionalExtendedType
and implements the given
implementedTypes
CompileException
IOException
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