1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/task4/solution07/src/org/apidesign/apifest08/currency/MonetaryAmount.java	Sat Oct 11 23:38:46 2008 +0200
     1.3 @@ -0,0 +1,89 @@
     1.4 +package org.apidesign.apifest08.currency;
     1.5 +
     1.6 +import java.math.BigDecimal;
     1.7 +import java.util.Currency;
     1.8 +
     1.9 +/**
    1.10 + * An amount of a currency.
    1.11 + * Immutable.
    1.12 + * @author jdvorak
    1.13 + */
    1.14 +public class MonetaryAmount {
    1.15 +
    1.16 +    private final BigDecimal amount;
    1.17 +    private final Currency currency;
    1.18 +    
    1.19 +    /**
    1.20 +     * A new amount.
    1.21 +     * @param amount the quantity of the currency; must not be null
    1.22 +     * @param currency the currency; must not be null
    1.23 +     */
    1.24 +    public MonetaryAmount( final BigDecimal amount, final Currency currency ) {
    1.25 +        this.amount = amount;
    1.26 +        this.currency = currency;
    1.27 +        if ( amount == null ) {
    1.28 +            throw new NullPointerException( "The amount" );
    1.29 +        }
    1.30 +        if ( currency == null ) {
    1.31 +            throw new NullPointerException( "The currency" );
    1.32 +        }
    1.33 +    }
    1.34 +    
    1.35 +    /**
    1.36 +     * A new amount.
    1.37 +     * @param amount the quantity of the currency; must not be null
    1.38 +     * @param currency the currency; must not be null
    1.39 +     */
    1.40 +    public MonetaryAmount( final double amount, final Currency currency ) {
    1.41 +        this( new BigDecimal( amount ), currency );
    1.42 +    }
    1.43 +    
    1.44 +    /**
    1.45 +     * The amount.
    1.46 +     * @return the amount
    1.47 +     */
    1.48 +    public BigDecimal getAmount() {
    1.49 +        return amount;
    1.50 +    }
    1.51 +    
    1.52 +    /**
    1.53 +     * The currency.
    1.54 +     * @return the currency
    1.55 +     */
    1.56 +    public Currency getCurrency() {
    1.57 +        return currency;
    1.58 +    }
    1.59 +
    1.60 +    /**
    1.61 +     * The string representation of the monetary amount.
    1.62 +     * @return the amount, a non-breakable space, the currency
    1.63 +     */
    1.64 +    @Override
    1.65 +    public String toString() {
    1.66 +        return amount.toPlainString() + "\u00a0" + currency.toString();
    1.67 +    }
    1.68 +    
    1.69 +    /**
    1.70 +     * Two monetary amounts are equal to each other iff they have equal amounts of equal currencies.
    1.71 +     * @param other the other object
    1.72 +     * @return equality
    1.73 +     */
    1.74 +    @Override
    1.75 +    public boolean equals( final Object other ) {
    1.76 +        if ( other instanceof MonetaryAmount ) {
    1.77 +            final MonetaryAmount otherMonetaryAmount = (MonetaryAmount) other;
    1.78 +            return getAmount().equals( otherMonetaryAmount.getAmount() ) && getCurrency().equals( otherMonetaryAmount.getCurrency() );
    1.79 +        }
    1.80 +        return false;
    1.81 +    }
    1.82 +    
    1.83 +    /**
    1.84 +     * The hash code combines the hash codes of the amount and of the currency.
    1.85 +     * @return hash code
    1.86 +     */
    1.87 +    @Override
    1.88 +    public int hashCode() {
    1.89 +        return amount.hashCode() * 37 + currency.hashCode();
    1.90 +    }
    1.91 +    
    1.92 +}