gnu.mapping
Class MethodProc

java.lang.Object
  gnu.mapping.PropertySet
      gnu.mapping.Procedure
          gnu.mapping.ProcedureN
              gnu.mapping.MethodProc

All Implemented Interfaces:

Named

Direct Known Subclasses:

AppendValues, Attributes, callcc, Children, CommentConstructor, Continuation, GenericProc, GetRequest, GetResponse, IntegerRange, IteratorItems, ListItems, MakeCDATA, MakeResponseHeader, ModuleMethod, NodeConstructor, OrderedMap, PrimProcedure, Q2Apply, RelativeStep, SubList, TreeScanner, TypeSwitch, ValuesEvery, ValuesFilter, ValuesMap

public abstract class MethodProc
extends ProcedureN

Similar to a CLOS method. Can check if arguments "match" before committing to calling method.

Field Summary

protected java.lang.Object	argTypes The parameter types.
static int	NO_MATCH Return code from match: Unspecified failure.
static int	NO_MATCH_AMBIGUOUS Return code from match: Ambigious which method to select.
static int	NO_MATCH_BAD_TYPE Return code from match: Invalid argument type.
static int	NO_MATCH_TOO_FEW_ARGS Return code from match: Too few actual arguments.
static int	NO_MATCH_TOO_MANY_ARGS Return code from match: Too many actual arguments.

Fields inherited from class gnu.mapping.ProcedureN

noArgs

Constructor Summary

MethodProc()

Method Summary

java.lang.Object	applyN(java.lang.Object[] args)
Type	getParameterType(int index)
int	isApplicable(Type[] argTypes) Test if method is applicable to an invocation with given arguments.
static java.lang.RuntimeException	matchFailAsException(int code, Procedure proc, java.lang.Object[] args) Helper method to throw an exception if a matchX method fails.
static int	mostSpecific(MethodProc[] procs, int length) Return the index of the most specific method.
static MethodProc	mostSpecific(MethodProc proc1, MethodProc proc2) Return the more specific of the arguments.
int	numParameters() Return number of parameters, including optional and rest arguments.
protected void	resolveParameterTypes() Figure out or decode the parameter types, setting argTypes.

Methods inherited from class gnu.mapping.ProcedureN

apply0, apply1, apply2, apply3, apply4

Methods inherited from class gnu.mapping.Procedure

apply, apply, check0, check1, check2, check3, check4, checkArgCount, checkN, getSetter, getSourceLocation, match0, match1, match2, match3, match4, matchN, maxArgs, minArgs, numArgs, set0, set1, setN, setSetter, setSourceLocation, toString

Methods inherited from class gnu.mapping.PropertySet

getName, getProperty, getSymbol, removeProperty, setName, setProperty, setProperty, setSymbol

Methods inherited from class java.lang.Object

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

Field Detail

argTypes

protected java.lang.Object argTypes

The parameter types. Usually either an Type[] or a String encoding.

NO_MATCH

public static final int NO_MATCH

Return code from match: Unspecified failure.

See Also:

Constant Field Values

NO_MATCH_TOO_FEW_ARGS

public static final int NO_MATCH_TOO_FEW_ARGS

Return code from match: Too few actual arguments. The lower half is the minimum number of arguments (if not 0xffff).

See Also:

Constant Field Values

NO_MATCH_TOO_MANY_ARGS

public static final int NO_MATCH_TOO_MANY_ARGS

Return code from match: Too many actual arguments. The lower half is the maximum number of arguments (if not 0xffff).

See Also:

Constant Field Values

NO_MATCH_AMBIGUOUS

public static final int NO_MATCH_AMBIGUOUS

Return code from match: Ambigious which method to select.

See Also:

Constant Field Values

NO_MATCH_BAD_TYPE

public static final int NO_MATCH_BAD_TYPE

Return code from match: Invalid argument type. In that case the lower half is the 1-origin index of the first argument that does not match.

See Also:

Constant Field Values

Constructor Detail

MethodProc

public MethodProc()

Method Detail

isApplicable

public int isApplicable(Type[] argTypes)

Test if method is applicable to an invocation with given arguments. Returns -1 if no; 1 if yes; 0 if need to check at run-time.

numParameters

public int numParameters()

Return number of parameters, including optional and rest arguments.

resolveParameterTypes

protected void resolveParameterTypes()

Figure out or decode the parameter types, setting argTypes.

getParameterType

public Type getParameterType(int index)

matchFailAsException

public static java.lang.RuntimeException matchFailAsException(int code,
                                                              Procedure proc,
                                                              java.lang.Object[] args)

Helper method to throw an exception if a matchX method fails.

applyN

public java.lang.Object applyN(java.lang.Object[] args)
                        throws java.lang.Throwable

Specified by:

applyN in class ProcedureN

Throws:

java.lang.Throwable

mostSpecific

public static MethodProc mostSpecific(MethodProc proc1,
                                      MethodProc proc2)

Return the more specific of the arguments.

Returns:

null if neither is more specific.

mostSpecific

public static int mostSpecific(MethodProc[] procs,
                               int length)

Return the index of the most specific method.