mapFunction.java :  » Scripting » Pnuts » org » pnuts » lib » Java Open Source

/*
 * @(#)mapFunction.java 1.2 04/12/06
 *
 * Copyright (c) 1997-2004 Sun Microsystems, Inc. All Rights Reserved.
 *
 * See the file "LICENSE.txt" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */
package org.pnuts.lib;

import java.lang.reflect.Array;
import java.util.*;
import pnuts.lang.*;
import pnuts.lang.Runtime;
import pnuts.lang.Package;

public class mapFunction extends PnutsFunction {

  public mapFunction(){
    super("mapFunction");
  }
  
  public boolean defined(int nargs){
    return (nargs == 2 || nargs == 3);
  }

  protected Object exec(Object args[], final Context context){
    int nargs = args.length;
    if (nargs != 2 && nargs != 3){
      undefined(args, context);
    }
    final PnutsFunction func = (PnutsFunction)args[0];
    Object array = args[1];

    int len = 0;
    int type1 = 0; // 1==array, 2==Collection, 3==Iterator, 4==Enumeration, 5==Map
    if (Runtime.isArray(array)){
      len = Runtime.getArrayLength(array);
      type1 = 1;
    } else if (array instanceof Collection){
      len = ((Collection)array).size();
      type1 = 2;
    } else if (array instanceof Iterator){
      type1 = 3;
    } else if (array instanceof Enumeration){
      type1 = 4;
    } else if (array instanceof Map){
      type1 = 5;
    } else if (array instanceof Package){
      type1 = 6;
    } else if (array instanceof Generator){
      type1 = 7;
    } else {
      throw new IllegalArgumentException();
    }

    Collection output = null;
    if (nargs == 3){
      if (args[2] instanceof Collection){
        output = (Collection)args[2];
      } else {
        throw new IllegalArgumentException();
      }
    }
       
    if (type1 == 1){ // array
      if (output == null){
        for (int i = 0; i < len; ++i){
          func.call(new Object[]{Array.get(array, i)}, context);
        }
      } else {
        for (int i = 0; i < len; ++i){
          output.add(func.call(new Object[]{Array.get(array, i)}, context));
        }
      }
    } else if (type1 == 2){ // Collection
      if (output == null){
        for (Iterator it = ((Collection)array).iterator(); it.hasNext(); ){
          func.call(new Object[]{it.next()}, context);
        }
      } else {
        for (Iterator it = ((Collection)array).iterator(); it.hasNext(); ){
          output.add(func.call(new Object[]{it.next()}, context));
        }
      }
    } else if (type1 == 3){ // Iterator
      if (output == null){
        for (Iterator it = (Iterator)array; it.hasNext(); ){
          func.call(new Object[]{it.next()}, context);
        }
      } else {
        for (Iterator it = (Iterator)array; it.hasNext(); ){
          output.add(func.call(new Object[]{it.next()}, context));
        }
      }
    } else if (type1 == 4){ // Enumeration
      if (output == null){
        for (Enumeration e = (Enumeration)array; e.hasMoreElements(); ){
          func.call(new Object[]{e.nextElement()}, context);
        }
      } else {
        for (Enumeration e = (Enumeration)array; e.hasMoreElements(); ){
          output.add(func.call(new Object[]{e.nextElement()}, context));
        }
      }
    } else if (type1 == 5){ // Map
      if (output == null){
        for (Iterator it = ((Map)array).entrySet().iterator(); it.hasNext(); ){
          Map.Entry entry = (Map.Entry)it.next();
          func.call(new Object[]{entry.getKey(), entry.getValue()}, context);
        }
      } else {
        for (Iterator it = ((Map)array).entrySet().iterator(); it.hasNext(); ){
          Map.Entry entry = (Map.Entry)it.next();
          output.add(func.call(new Object[]{entry.getKey(), entry.getValue()}, context));
        }
      }
    } else if (type1 == 6){ // Package
      if (output == null){
        for (Enumeration e = ((Package)array).bindings(); e.hasMoreElements(); ){
          NamedValue value = (NamedValue)e.nextElement();
          func.call(new Object[]{value.getName(), value.get()}, context);
        }
      } else {
        for (Enumeration e = ((Package)array).bindings(); e.hasMoreElements(); ){
          NamedValue value = (NamedValue)e.nextElement();
          output.add(func.call(new Object[]{value.getName(), value.get()}, context));
        }
      }
    } else if (type1 == 7){
      Generator g = (Generator)array;
      if (output == null){
        return Runtime.applyGenerator(g,
                        new PnutsFunction(){
                          protected Object exec(Object[] args, Context ctx){
                            func.call(args, ctx);
                            return null;
                          }
                        }, context);
      } else {
        final Collection output2 = output;
        return Runtime.applyGenerator(g,
                        new PnutsFunction(){
                          protected Object exec(Object[] args, Context ctx){
                            output2.add(func.call(args, ctx));
                            return null;
                          }
                        }, context);
      }
    }
    return null;
  }

  public String toString(){
    return "function mapFunction(func, (array|Collection|Iterator|Enumeration|Map|Package|Generator ) {, Collection } )";
  }
}