blob: 6f967a1c42ee9734db23a366866c6734b8ae5673 [file] [log] [blame]
package com.googlecode.prolog_cafe.builtin;
import com.googlecode.prolog_cafe.exceptions.ExistenceException;
import com.googlecode.prolog_cafe.exceptions.IllegalDomainException;
import com.googlecode.prolog_cafe.exceptions.IllegalTypeException;
import com.googlecode.prolog_cafe.exceptions.PInstantiationException;
import com.googlecode.prolog_cafe.exceptions.PermissionException;
import com.googlecode.prolog_cafe.exceptions.RepresentationException;
import com.googlecode.prolog_cafe.lang.JavaObjectTerm;
import com.googlecode.prolog_cafe.lang.Operation;
import com.googlecode.prolog_cafe.lang.Predicate;
import com.googlecode.prolog_cafe.lang.Prolog;
import com.googlecode.prolog_cafe.lang.SymbolTerm;
import com.googlecode.prolog_cafe.lang.Term;
import com.googlecode.prolog_cafe.lang.VariableTerm;
import java.io.PrintWriter;
/**
<code>put_char/2</code><br>
@author Mutsunori Banbara (banbara@kobe-u.ac.jp)
@author Naoyuki Tamura (tamura@kobe-u.ac.jp)
@version 1.0
*/
public class PRED_put_char_2 extends Predicate.P2 {
public PRED_put_char_2(Term a1, Term a2, Operation cont) {
arg1 = a1;
arg2 = a2;
this.cont = cont;
}
@Override
public Operation exec(Prolog engine) {
engine.setB0();
Term a1, a2;
a1 = arg1;
a2 = arg2;
String str;
char c;
Object stream = null;
// Char
a2 = a2.dereference();
if (a2 instanceof VariableTerm)
throw new PInstantiationException(this, 2);
if (! (a2 instanceof SymbolTerm))
throw new IllegalTypeException(this, 2, "character", a2);
// S_or_a
a1 = a1.dereference();
if (a1 instanceof VariableTerm) {
throw new PInstantiationException(this, 1);
} else if (a1 instanceof SymbolTerm) {
if (! engine.getStreamManager().containsKey(a1))
throw new ExistenceException(this, 1, "stream", a1, "");
stream = ((JavaObjectTerm) engine.getStreamManager().get(a1)).object();
} else if (a1 instanceof JavaObjectTerm) {
stream = ((JavaObjectTerm) a1).object();
} else {
throw new IllegalDomainException(this, 1, "stream_or_alias", a1);
}
if (! (stream instanceof PrintWriter))
throw new PermissionException(this, "output", "stream", a1, "");
// print single character
str = ((SymbolTerm)a2).name();
if (str.length() != 1)
throw new IllegalTypeException(this, 2, "character", a2);
c = str.charAt(0);
if (! Character.isDefined(c))
throw new RepresentationException(this, 2, "character");
((PrintWriter) stream).print(c);
return cont;
}
}