com.codename1.util.BigDecimal Maven / Gradle / Ivy
/*
* This code originates from the bouncy castle library and didn't have a copyright header
*/
package com.codename1.util;
/**
* Class representing a simple version of a big decimal. A
* BigDecimal is basically a
* {@link java.math.BigInteger BigInteger} with a few digits on the right of
* the decimal point. The number of (binary) digits on the right of the decimal
* point is called the scale of the BigDecimal.
* Unlike in {@link java.math.BigDecimal BigDecimal}, the scale is not adjusted
* automatically, but must be set manually. All BigDecimals
* taking part in the same arithmetic operation must have equal scale. The
* result of a multiplication of two BigDecimals returns a
* BigDecimal with double scale.
*/
public class BigDecimal {
private static final BigInteger ZERO = BigInteger.valueOf(0);
private static final BigInteger ONE = BigInteger.valueOf(1);
//private final BigInteger bigInt;
//private final int scale;
TBigDecimal peer;
/**
* Returns a BigDecimal with value value / 2scale / 10scale
* @param value The value of the BigDecimal to be
* created.
* @param scale The scale of the BigDecimal to be
* created.
* @return The such created BigDecimal.
* @deprecated This method is not part of the JDK's BigDecimal class and its presence is historical,
* as the first implementation of Codename One's BigDecimal class was ported from BouncyCastle, which is different
* than the JDK's BigDecimal class in that is optimizes binary arithmetic. The implementation of this method
* is counter-intuitive since it performs a bitwise left shift on value before scaling it. Use {@link #BigDecimal(com.codename1.util.BigInteger, int) }
* instead if you just want to convert a BigInteger into a BigDecimal. Do not rely on this method
* as it will be removed in a future version of Codename One..
*/
public static BigDecimal getInstance(BigInteger value, int scale)
{
return new BigDecimal(value.shiftLeft(scale), scale);
}
/**
* Constructor for BigDecimal. The value of the
* constructed BigDecimal equals bigInt /
* 10scale.
* @param bigInt The bigInt value parameter.
* @param scale The scale of the constructed BigDecimal.
*/
public BigDecimal(BigInteger bigInt, int scale)
{
peer = new TBigDecimal(bigInt.peer, scale);
}
private BigDecimal(BigDecimal limBigDec)
{
peer = new TBigDecimal(limBigDec.toString());
}
private BigDecimal(TBigDecimal peer) {
this.peer = peer;
}
public BigDecimal adjustScale(int newScale)
{
return new BigDecimal(peer.setScale(newScale));
}
public BigDecimal add(BigDecimal b)
{
return new BigDecimal(peer.add(b.peer));
}
public BigDecimal add(BigInteger b)
{
return new BigDecimal(peer.add(new TBigDecimal(b.peer, 0)));
}
public BigDecimal negate()
{
return new BigDecimal(peer.negate());
}
public BigDecimal subtract(BigDecimal b)
{
return new BigDecimal(peer.subtract(b.peer));
}
public BigDecimal subtract(BigInteger b)
{
return new BigDecimal(peer.subtract(new TBigDecimal(b.peer, 0)));
}
public BigDecimal multiply(BigDecimal b)
{
return new BigDecimal(peer.multiply(b.peer));
}
public BigDecimal multiply(BigInteger b)
{
return new BigDecimal(peer.multiply(new TBigDecimal(b.peer, 0)));
}
public BigDecimal divide(BigDecimal b)
{
return new BigDecimal(peer.divide(b.peer));
}
public BigDecimal divide(BigInteger b)
{
return new BigDecimal(peer.divide(new TBigDecimal(b.peer, 0)));
}
public BigDecimal shiftLeft(int n)
{
throw new RuntimeException("Not implemented yet");
}
public int compareTo(BigDecimal val)
{
return peer.compareTo(val.peer);
}
public int compareTo(BigInteger val)
{
return peer.compareTo(new TBigDecimal(val.peer, 0));
}
public BigInteger floor()
{
BigInteger out = new BigInteger(peer.toBigInteger());
if (peer.signum() < 0) {
return out.subtract(new BigInteger("1",0));
}
return out;
}
public BigInteger round()
{
BigInteger out = new BigInteger(peer.toBigInteger());
BigDecimal outD = new BigDecimal(out, 0);
BigInteger next = peer.signum() < 0 ? out.subtract(BigInteger.ONE) : out.add(BigInteger.ONE);
BigDecimal nextD = new BigDecimal(next, 0);
BigDecimal diffThis = new BigDecimal(outD.peer.abs().subtract(peer.abs()).abs());
BigDecimal diffNext = new BigDecimal(outD.peer.abs().subtract(nextD.peer.abs()).abs());
return diffThis.compareTo(diffNext) > 0 ? out : next;
}
public int intValue()
{
return floor().intValue();
}
public long longValue()
{
return floor().longValue();
}
/* NON-J2ME compliant.
public double doubleValue()
{
return Double.valueOf(toString()).doubleValue();
}
public float floatValue()
{
return Float.valueOf(toString()).floatValue();
}
*/
public int getScale()
{
return peer.scale();
}
public String toString()
{
return peer.toString();
}
public boolean equals(Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof BigDecimal))
{
return false;
}
BigDecimal other = (BigDecimal)o;
return peer.equals(other.peer);
}
public int hashCode()
{
return peer.hashCode();
}
}