| package jp.ac.kobe_u.cs.prolog.builtin; |
| import jp.ac.kobe_u.cs.prolog.lang.*; |
| /** |
| <code>'$statistics'/2</code><br> |
| @author Mutsunori Banbara (banbara@kobe-u.ac.jp) |
| @author Naoyuki Tamura (tamura@kobe-u.ac.jp) |
| @version 1.0 |
| */ |
| class PRED_$statistics_2 extends Predicate { |
| public static SymbolTerm Nil = SymbolTerm.makeSymbol("[]"); |
| public static SymbolTerm SYM_RUNTIME = SymbolTerm.makeSymbol("runtime"); |
| public static SymbolTerm SYM_TRAIL = SymbolTerm.makeSymbol("trail"); |
| public static SymbolTerm SYM_CHOICE = SymbolTerm.makeSymbol("choice"); |
| |
| Term arg1, arg2; |
| |
| public PRED_$statistics_2(Term a1, Term a2, Predicate cont){ |
| arg1 = a1; |
| arg2 = a2; |
| this.cont = cont; |
| } |
| public PRED_$statistics_2(){} |
| |
| public void setArgument(Term[] args, Predicate cont){ |
| arg1 = args[0]; |
| arg2 = args[1]; |
| this.cont = cont; |
| } |
| |
| public int arity() { return 2 ; } |
| |
| public String toString(){ return "$statistics(" + arg1 + "," + arg2 + ")"; } |
| |
| public Predicate exec(Prolog engine){ |
| engine.setB0(); |
| Term a1, a2; |
| a1 = arg1; |
| a2 = arg2; |
| Term result = null; |
| |
| a1 = a1.dereference(); |
| if (a1.isVariable()) { |
| throw new PInstantiationException(this, 1); |
| } else if (! a1.isSymbol()) { |
| throw new IllegalTypeException(this, 1, "atom", a1); |
| } else if (a1.equals(SYM_RUNTIME)) { |
| long val1, val2; |
| Term start, previous; |
| val1 = System.currentTimeMillis() - engine.getStartRuntime(); |
| val2 = val1 - engine.getPreviousRuntime(); |
| engine.setPreviousRuntime(val1); |
| start = new IntegerTerm((int)val1); |
| previous = new IntegerTerm((int)val2); |
| result = new ListTerm(start, new ListTerm(previous, Nil)); |
| } else if (a1.equals(SYM_TRAIL)) { |
| int top, max; |
| Term free, used; |
| top = engine.trail.top(); |
| max = engine.trail.max(); |
| used = new IntegerTerm(top); |
| free = new IntegerTerm(max - top); |
| result = new ListTerm(used, new ListTerm(free, Nil)); |
| } else if (a1.equals(SYM_CHOICE)) { |
| int top, max; |
| Term free, used; |
| top = engine.stack.top(); |
| max = engine.stack.max(); |
| used = new IntegerTerm(top); |
| free = new IntegerTerm(max - top); |
| result = new ListTerm(used, new ListTerm(free, Nil)); |
| } else { |
| return engine.fail(); |
| } |
| if (! a2.unify(result, engine.trail)) |
| return engine.fail(); |
| return cont; |
| } |
| } |