commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Loic Guibert <lguib...@apache.org>
Subject Re: [LANG] Adding null safe compare methods in StringUtils
Date Tue, 20 Oct 2015 15:28:09 GMT
I've updated my pull request if you want to look at what I plan to do
concerning methods exclusion in
StringUtilsTest.testStringUtilsCharSequenceContract()

https://github.com/apache/commons-lang/pull/110
https://github.com/apache/commons-lang/commit/131917a0d3303ca2c38fd1d6765b9bed2c23ff89
 

Loic Guibert
PGP : 0x65EB4F33

Le 20/10/2015 17:24, Loic Guibert a écrit :
> Hi Benedikt,
> There are exactly the two options I was considering.
>
> If nobody objects, I'll go on the second way and exclude those methods in
> StringUtilsTest.testStringUtilsCharSequenceContract().
>
> This is closer to Java conception where CharSequence are not comparable and
> comparing two CharSequence of distinct nature
> (like StringBuilder & CharBuffer for exemple)
> may be undefined and can cause some problems
> (like in CharBuffer where length method return remaining char
> and not the total CharSequence length
> or charAt(int index) that return the (current position + index)th char).
>
> Loic Guibert
> PGP : 0x65EB4F33
>
>
> Le 06/10/2015 23:07, Benedikt Ritter a écrit :
>> Hi Loic,
>>
>> first of all, I like this proposal. Thank you for that!
>>
>> Regarding your question I see two options:
>> - implement compare so that is accepts CharSequences as well. That would
>> mean to implement a compare for CharSequences which compares two sequences
>> character by character
>> - exclude the compare methods
>>
>> Benedikt
>>
>> 2015-10-05 15:32 GMT+02:00 Loic Guibert <lfdummy-apache@yahoo.fr>:
>>
>>> But i've a problem in this unit test :
>>>
>>> org.apache.commons.lang3.StringUtilsTest.testStringUtilsCharSequenceContract()
>>>
>>> It said :
>>>
>>> The method public static int
>>> org.apache.commons.lang3.StringUtils.compare(String,String,boolean) appears
>>> to be immutable in spirit and therefore must not accept a String
>>>
>>> I use String parameters instead of CharSequence because in the Java
>>> conception, only String are Comparable and not CharSequence.
>>> I call String#compareTo(String) in the implementation.
>>>
>>> So what should I do ?
>>>
>>> Loic Guibert
>>> PGP : 0x65EB4F33
>>>
>>>
>>>
>>> Le 05/10/2015 17:19, Loic Guibert a écrit :
>>>> Hello,
>>>> I've implemented null safe methods to compare 2 Strings in StringUtils :
>>>>   - public static int compare(final String str1, final String str2);
>>>>   - public static int compare(final String str1, final String str2,
>>>> final boolean nullIsLess);
>>>>   - public static int compareIgnoreCase(final String str1, final String
>>>> str2);
>>>>   - public static int compareIgnoreCase(final String str1, final String
>>>> str2, final boolean nullIsLess);
>>>>
>>>>
>>>> I opened a JIRA ticket and an associated Pull Request to add those
>>>> methods in StringUtils :
>>>>   - https://issues.apache.org/jira/browse/LANG-1171
>>>>   - https://github.com/apache/commons-lang/pull/110
>>>>
>>>>
>>>> More details :
>>>> /**
>>>>  * <p>Compare two Strings lexicographically, as per {@link
>>>> String#compareTo(String)}, returning :</p>
>>>>  * <ul>
>>>>  *  <li>{@code int = 0}, if {@code str1} is equal to {@code str2} (or
>>>> both {@code null})</li>
>>>>  *  <li>{@code int < 0}, if {@code str1} is less than {@code str2}</li>
>>>>  *  <li>{@code int > 0}, if {@code str1} is greater than {@code
>>> str2}</li>
>>>>  * </ul>
>>>>  *
>>>>  * <p>This is a {@code null} safe version of :</p>
>>>>  * <blockquote><pre>str1.compareTo(str2)</pre></blockquote>
>>>>  *
>>>>  * <p>{@code null} value is considered less than non-{@code null} value.
>>>>  * Two {@code null} references are considered equal.</p>
>>>>  *
>>>>  * <pre>
>>>>  * StringUtils.compare(null, null)   = 0
>>>>  * StringUtils.compare(null , "a")   &lt; 0
>>>>  * StringUtils.compare("a", null)    &gt; 0
>>>>  * StringUtils.compare("abc", "abc") = 0
>>>>  * StringUtils.compare("a", "b")     &lt; 0
>>>>  * StringUtils.compare("b", "a")     &gt; 0
>>>>  * StringUtils.compare("a", "B")     &gt; 0
>>>>  * StringUtils.compare("ab", "abc")  &lt; 0
>>>>  * </pre>
>>>>  *
>>>>  * @see #compare(String, String, boolean)
>>>>  * @see String#compareTo(String)
>>>>  * @param str1  the String to compare from
>>>>  * @param str2  the String to compare to
>>>>  * @return &lt; 0, 0, &gt; 0, if {@code str1} is respectively less,
>>>> equal ou greater than {@code str2}
>>>>  */
>>>> public static int compare(final String str1, final String str2);
>>>>
>>>> /**
>>>>  * <p>Compare two Strings lexicographically, as per {@link
>>>> String#compareTo(String)}, returning :</p>
>>>>  * <ul>
>>>>  *  <li>{@code int = 0}, if {@code str1} is equal to {@code str2} (or
>>>> both {@code null})</li>
>>>>  *  <li>{@code int < 0}, if {@code str1} is less than {@code str2}</li>
>>>>  *  <li>{@code int > 0}, if {@code str1} is greater than {@code
>>> str2}</li>
>>>>  * </ul>
>>>>  *
>>>>  * <p>This is a {@code null} safe version of :</p>
>>>>  * <blockquote><pre>str1.compareTo(str2)</pre></blockquote>
>>>>  *
>>>>  * <p>{@code null} inputs are handled according to the {@code
>>>> nullIsLess} parameter.
>>>>  * Two {@code null} references are considered equal.</p>
>>>>  *
>>>>  * <pre>
>>>>  * StringUtils.compare(null, null, *)     = 0
>>>>  * StringUtils.compare(null , "a", true)  &lt; 0
>>>>  * StringUtils.compare(null , "a", false) &gt; 0
>>>>  * StringUtils.compare("a", null, true)   &gt; 0
>>>>  * StringUtils.compare("a", null, false)  &lt; 0
>>>>  * StringUtils.compare("abc", "abc", *)   = 0
>>>>  * StringUtils.compare("a", "b", *)       &lt; 0
>>>>  * StringUtils.compare("b", "a", *)       &gt; 0
>>>>  * StringUtils.compare("a", "B", *)       &gt; 0
>>>>  * StringUtils.compare("ab", "abc", *)    &lt; 0
>>>>  * </pre>
>>>>  *
>>>>  * @see String#compareTo(String)
>>>>  * @param str1  the String to compare from
>>>>  * @param str2  the String to compare to
>>>>  * @param nullIsLess  whether consider {@code null} value less than
>>>> non-{@code null} value
>>>>  * @return &lt; 0, 0, &gt; 0, if {@code str1} is respectively less,
>>>> equal ou greater than {@code str2}
>>>>  */
>>>> public static int compare(final String str1, final String str2, final
>>>> boolean nullIsLess);
>>>>
>>>> /**
>>>>  * <p>Compare two Strings lexicographically, ignoring case differences,
>>>>  * as per {@link String#compareToIgnoreCase(String)}, returning :</p>
>>>>  * <ul>
>>>>  *  <li>{@code int = 0}, if {@code str1} is equal to {@code str2} (or
>>>> both {@code null})</li>
>>>>  *  <li>{@code int < 0}, if {@code str1} is less than {@code str2}</li>
>>>>  *  <li>{@code int > 0}, if {@code str1} is greater than {@code
>>> str2}</li>
>>>>  * </ul>
>>>>  *
>>>>  * <p>This is a {@code null} safe version of :</p>
>>>>  * <blockquote><pre>str1.compareToIgnoreCase(str2)</pre></blockquote>
>>>>  *
>>>>  * <p>{@code null} value is considered less than non-{@code null} value.
>>>>  * Two {@code null} references are considered equal.
>>>>  * Comparison is case insensitive.</p>
>>>>  *
>>>>  * <pre>
>>>>  * StringUtils.compareIgnoreCase(null, null)   = 0
>>>>  * StringUtils.compareIgnoreCase(null , "a")   &lt; 0
>>>>  * StringUtils.compareIgnoreCase("a", null)    &gt; 0
>>>>  * StringUtils.compareIgnoreCase("abc", "abc") = 0
>>>>  * StringUtils.compareIgnoreCase("abc", "ABC") = 0
>>>>  * StringUtils.compareIgnoreCase("a", "b")     &lt; 0
>>>>  * StringUtils.compareIgnoreCase("b", "a")     &gt; 0
>>>>  * StringUtils.compareIgnoreCase("a", "B")     &lt; 0
>>>>  * StringUtils.compareIgnoreCase("A", "b")     &lt; 0
>>>>  * StringUtils.compareIgnoreCase("ab", "ABC")  &lt; 0
>>>>  * </pre>
>>>>  *
>>>>  * @see #compareIgnoreCase(String, String, boolean)
>>>>  * @see String#compareToIgnoreCase(String)
>>>>  * @param str1  the String to compare from
>>>>  * @param str2  the String to compare to
>>>>  * @return &lt; 0, 0, &gt; 0, if {@code str1} is respectively less,
>>>> equal ou greater than {@code str2},
>>>>  *          ignoring case differences.
>>>>  */
>>>> public static int compareIgnoreCase(final String str1, final String
>>> str2);
>>>> /**
>>>>  * <p>Compare two Strings lexicographically, ignoring case differences,
>>>>  * as per {@link String#compareToIgnoreCase(String)}, returning :</p>
>>>>  * <ul>
>>>>  *  <li>{@code int = 0}, if {@code str1} is equal to {@code str2} (or
>>>> both {@code null})</li>
>>>>  *  <li>{@code int < 0}, if {@code str1} is less than {@code str2}</li>
>>>>  *  <li>{@code int > 0}, if {@code str1} is greater than {@code
>>> str2}</li>
>>>>  * </ul>
>>>>  *
>>>>  * <p>This is a {@code null} safe version of :</p>
>>>>  * <blockquote><pre>str1.compareToIgnoreCase(str2)</pre></blockquote>
>>>>  *
>>>>  * <p>{@code null} inputs are handled according to the {@code
>>>> nullIsLess} parameter.
>>>>  * Two {@code null} references are considered equal.
>>>>  * Comparison is case insensitive.</p>
>>>>  *
>>>>  * <pre>
>>>>  * StringUtils.compareIgnoreCase(null, null, *)     = 0
>>>>  * StringUtils.compareIgnoreCase(null , "a", true)  &lt; 0
>>>>  * StringUtils.compareIgnoreCase(null , "a", false) &gt; 0
>>>>  * StringUtils.compareIgnoreCase("a", null, true)   &gt; 0
>>>>  * StringUtils.compareIgnoreCase("a", null, false)  &lt; 0
>>>>  * StringUtils.compareIgnoreCase("abc", "abc", *)   = 0
>>>>  * StringUtils.compareIgnoreCase("abc", "ABC", *)   = 0
>>>>  * StringUtils.compareIgnoreCase("a", "b", *)       &lt; 0
>>>>  * StringUtils.compareIgnoreCase("b", "a", *)       &gt; 0
>>>>  * StringUtils.compareIgnoreCase("a", "B", *)       &lt; 0
>>>>  * StringUtils.compareIgnoreCase("A", "b", *)       &lt; 0
>>>>  * StringUtils.compareIgnoreCase("ab", "abc", *)    &lt; 0
>>>>  * </pre>
>>>>  *
>>>>  * @see String#compareToIgnoreCase(String)
>>>>  * @param str1  the String to compare from
>>>>  * @param str2  the String to compare to
>>>>  * @param nullIsLess  whether consider {@code null} value less than
>>>> non-{@code null} value
>>>>  * @return &lt; 0, 0, &gt; 0, if {@code str1} is respectively less,
>>>> equal ou greater than {@code str2},
>>>>  *          ignoring case differences.
>>>>  */
>>>> public static int compareIgnoreCase(final String str1, final String
>>>> str2, final boolean nullIsLess);
>>>>
>>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>
>>>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
> For additional commands, e-mail: dev-help@commons.apache.org
>


---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
For additional commands, e-mail: dev-help@commons.apache.org


Mime
View raw message