Java Zero Format zeroIfNullStrict(Integer i)

Description

converts an Integer to an int, mapping null to 0.

License

Open Source License

Parameter

Parameter	Description
i	a parameter

Exception

Parameter	Description
IllegalArgumentException	if <code>i</code> is <code>Integer(0)</code>.

Return

the intValue() of i, if i != null. 0 otherwise.

Declaration

public static int zeroIfNullStrict(Integer i) 

Method Source Code

//package com.java2s;
//it under the terms of the GNU Affero General Public License as published by

public class Main {
    /**/*ww  w .  j av  a 2s .  co m*/
     * converts an <code>Integer</code> to an <code>int</code>, mapping <code>null</code> to <code>0</code>.
     * Integer(0) is not allowed for input. This strict version of "nullToZeroStrict" is the inverse of <code>zeroToNull</code>,
     * always ensuring that <code>LangUtil.equals(zeroToNull(nullToZeroStrict(i)), i)</code>.
     * @param i
     * @return the <code>intValue()</code> of <code>i</code>, if <code>i != null</code>. <code>0</code> otherwise.
     * @throws IllegalArgumentException if <code>i</code> is <code>Integer(0)</code>.
     * @postcondition (i == null) --> (result == 0)
     * @postcondition (i != null) && (i != 0) --> (result == i)
     */
    public static int zeroIfNullStrict(Integer i) {
        final int result;
        if (i == null) {
            result = 0;
        } else {
            result = i;
            if (result == 0) {
                throw new IllegalArgumentException("langutils.integer.not.allowed.exception");//"Integer(0) ist nicht erlaubt.");
            }
        }

        // Note that "implies" doesn't work here:
        assert !(i == null) || (result == 0);
        assert !((i != null) && (i != 0)) || (result == i);

        return result;
    }
}

Related

1. zeroFillString(String originalString, int numZeros)
2. zeroFormat(Integer source)
3. zeroFormattedStr(int number, int length)
4. zeroIfNull(Integer i)
5. zeroIfNull(Integer i)
6. zeroInterval(byte[] x, int start, int end)
7. zeroLowerBits(long bits, int nBits)
8. zeroMatrix(int M, int N, double mat[][])
9. zeroObjects()