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package com.sun.tools.internal.xjc.model;

import java.math.BigInteger;



represents a possible number of occurence. Usually, denoted by a pair of integers like (1,1) or (5,10). A special value "unbounded" is allowed as the upper bound.

For example, (0,unbounded) corresponds to the '*' occurence of DTD. (0,1) corresponds to the '?' occurence of DTD.

Author: Kohsuke KAWAGUCHI
/** * represents a possible number of occurence. * * Usually, denoted by a pair of integers like (1,1) or (5,10). * A special value "unbounded" is allowed as the upper bound. * * <p> * For example, (0,unbounded) corresponds to the '*' occurence of DTD. * (0,1) corresponds to the '?' occurence of DTD. * * @author * <a href="mailto:kohsuke.kawaguchi@sun.com">Kohsuke KAWAGUCHI</a> */
public final class Multiplicity { public final BigInteger min; public final BigInteger max; // null is used to represent "unbounded". public static Multiplicity create(BigInteger min, BigInteger max ) { if (BigInteger.ZERO.equals(min) && max==null) return STAR; if (BigInteger.ONE.equals(min) && max==null) return PLUS; if (max!=null) { if(BigInteger.ZERO.equals(min) && BigInteger.ZERO.equals(max)) return ZERO; if(BigInteger.ZERO.equals(min) && BigInteger.ONE.equals(max)) return OPTIONAL; if(BigInteger.ONE.equals(min) && BigInteger.ONE.equals(max)) return ONE; } return new Multiplicity(min, max); } public static Multiplicity create(int min, Integer max ) { return Multiplicity.create(BigInteger.valueOf(min), BigInteger.valueOf(max.intValue())); } private Multiplicity(BigInteger min, BigInteger max) { this.min = min; this.max = max; } private Multiplicity(int min, int max) { this(BigInteger.valueOf(min), BigInteger.valueOf(max)); } private Multiplicity(int min, Integer max) { this(BigInteger.valueOf(min), (max == null) ? null : BigInteger.valueOf(max)); } @Override public boolean equals(Object o) { if (!(o instanceof Multiplicity)) return false; Multiplicity that = (Multiplicity) o; if (!this.min.equals(that.min)) return false; if (this.max != null ? !this.max.equals(that.max) : that.max != null) return false; return true; } @Override public int hashCode() { return min.add(max).intValue(); }
returns true if the multiplicity is (1,1).
/** returns true if the multiplicity is (1,1). */
public boolean isUnique() { if(max==null) return false; return BigInteger.ONE.equals(min) && BigInteger.ONE.equals(max); }
returns true if the multiplicity is (0,1)
/** returns true if the multiplicity is (0,1) */
public boolean isOptional() { if(max==null) return false; return BigInteger.ZERO.equals(min) && BigInteger.ONE.equals(max); }
returns true if the multiplicity is (0,1) or (1,1).
/** returns true if the multiplicity is (0,1) or (1,1). */
public boolean isAtMostOnce() { if(max==null) return false; return max.compareTo(BigInteger.ONE)<=0; }
returns true if the multiplicity is (0,0).
/** returns true if the multiplicity is (0,0). */
public boolean isZero() { if(max==null) return false; return BigInteger.ZERO.equals(max); }
Returns true if the multiplicity represented by this object completely includes the multiplicity represented by the other object. For example, we say [1,3] includes [1,2] but [2,4] doesn't include [1,3].
/** * Returns true if the multiplicity represented by this object * completely includes the multiplicity represented by the * other object. For example, we say [1,3] includes [1,2] but * [2,4] doesn't include [1,3]. */
public boolean includes( Multiplicity rhs ) { if (rhs.min.compareTo(min) == -1) return false; if (max==null) return true; if (rhs.max==null) return false; return rhs.max.compareTo(max) <= 0; }
Returns the string representation of the 'max' property. Either a number or a token "unbounded".
/** * Returns the string representation of the 'max' property. * Either a number or a token "unbounded". */
public String getMaxString() { if(max==null) return "unbounded"; else return max.toString(); }
gets the string representation. mainly debug purpose.
/** gets the string representation. * mainly debug purpose. */
@Override public String toString() { return "("+min+','+getMaxString()+')'; }
the constant representing the (0,0) multiplicity.
/** the constant representing the (0,0) multiplicity. */
public static final Multiplicity ZERO = new Multiplicity(0,0);
the constant representing the (1,1) multiplicity.
/** the constant representing the (1,1) multiplicity. */
public static final Multiplicity ONE = new Multiplicity(1,1);
the constant representing the (0,1) multiplicity.
/** the constant representing the (0,1) multiplicity. */
public static final Multiplicity OPTIONAL = new Multiplicity(0,1);
the constant representing the (0,unbounded) multiplicity.
/** the constant representing the (0,unbounded) multiplicity. */
public static final Multiplicity STAR = new Multiplicity(0,null);
the constant representing the (1,unbounded) multiplicity.
/** the constant representing the (1,unbounded) multiplicity. */
public static final Multiplicity PLUS = new Multiplicity(1,null); // arithmetic methods public static Multiplicity choice( Multiplicity lhs, Multiplicity rhs ) { return create( lhs.min.min(rhs.min), (lhs.max==null || rhs.max==null) ? null : lhs.max.max(rhs.max) ); } public static Multiplicity group( Multiplicity lhs, Multiplicity rhs ) { return create( lhs.min.add(rhs.min), (lhs.max==null || rhs.max==null) ? null : lhs.max.add(rhs.max) ); } public static Multiplicity multiply( Multiplicity lhs, Multiplicity rhs ) { BigInteger min = lhs.min.multiply(rhs.min); BigInteger max; if (isZero(lhs.max) || isZero(rhs.max)) max = BigInteger.ZERO; else if (lhs.max==null || rhs.max==null) max = null; else max = lhs.max.multiply(rhs.max); return create(min,max); } private static boolean isZero(BigInteger i) { return (i != null && BigInteger.ZERO.equals(i)); } public static Multiplicity oneOrMore( Multiplicity c ) { if(c.max==null) return c; // (x,*) => (x,*) if(BigInteger.ZERO.equals(c.max)) return c; // (0,0) => (0,0) else return create( c.min, null ); // (x,y) => (x,*) } public Multiplicity makeOptional() { if (BigInteger.ZERO.equals(min)) return this; return create(BigInteger.ZERO, max); } public Multiplicity makeRepeated() { if (max==null || BigInteger.ZERO.equals(max)) return this; // (0,0)* = (0,0) and (n,unbounded)* = (n,unbounded) return create(min,null); } }