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Krzysztof Nazarewski edited comment on LANG-810 at 7/11/12 8:43 AM: -------------------------------------------------------------------- Basically endIndex takes values from 1 to array.length instead of from 0 to {{(array.length - 1)}} In current state it is "1-based index", not "0-based index" while Java language uses 0-based indexes, also previous argument "startIndex" is also 0-based. If you put valid index 0, the for loop won't run at all as it checks (i < endIndex) like it was array's length. Let's say you have 1 element array to join (it does not make practical sense, bu should work), it has index 0 and does not have anything beyond 0 index. According to JavaDoc only possible combination of startIndex and endIndex would be (0,0). StringUtils.java, line 3394: {{for (int i = startIndex; i < endIndex; i++) {}} However for loop will not execute even single time because {{(i = startIndex = 0)}} is not lower than {{(endIndex = 0)}}, it is equal to endIndex and the result of joining single element array from it's only index 0 to index 0 will be empty string. Therefore to join that one-element array you need to use combination {{(startIndex = 0, endIndex = 1)}}, where {{(endIndex == array.length)}} is error according to JavaDoc: "endIndex - the index to stop joining from (exclusive). *It is an error to pass in an end index past the end of the array*" was (Author: drag0nius): Basically endIndex takes values from 1 to array.length instead of from 0 to (array.length - 1) and is not really index at all. If you put valid index 0, the for loop won't run at all as it checks (i < endIndex) like it was array's length. Let's say you have 1 element array to join (it does not make practical sense, bu should work), it has index 0 and does not have anything beyond 0 index. According to JavaDoc only possible combination of startIndex and endIndex would be (0,0). StringUtils.java, line 3394: {{for (int i = startIndex; i < endIndex; i++) {}} However for loop will not execute even single time because {{(i = startIndex = 0)}} is not lower than {{(endIndex = 0)}}, it is equal to endIndex and the result of joining single element array from it's only index 0 to index 0 will be empty string. Therefore to join that one-element array you need to use combination {{(startIndex = 0, endIndex = 1)}}, where {{(endIndex == array.length)}} is error according to JavaDoc: "endIndex - the index to stop joining from (exclusive). *It is an error to pass in an end index past the end of the array*" > StringUtils.join() endIndex, bugged for loop > -------------------------------------------- > > Key: LANG-810 > URL: https://issues.apache.org/jira/browse/LANG-810 > Project: Commons Lang > Issue Type: Bug > Components: lang.* > Affects Versions: 3.1 > Reporter: Krzysztof Nazarewski > Assignee: Joerg Schaible > Original Estimate: 1m > Remaining Estimate: 1m > > endIndex is described as index, but for loop still checks it as "array > length". > Basically missing equal sign > commons-lang3-3.1-sources.jar, StringUtils.java lines 3309, 3394: > for (int i = startIndex; i < endIndex; i++) { > should be: > for (int i = startIndex; i <= endIndex; i++) { -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira