[LANG-992] NumberUtils#isNumber() returns false for "0.0", "0.4790", et al

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Cannot Reproduce
• Affects Version/s: 3.3.1
• Component/s: lang.math.*

Environment

Java 8, Windows 7

• Assignee: Rob Tompkins
• Reporter: Adam Rauch
• Created: 26/Mar/14 21:26
• Updated: 19/Oct/16 15:24
• Resolved: 11/Sep/16 20:41

Description

After upgrading from 3.1 to 3.3.1, it seems that isNumber(String str) returns false for decimal numbers with leading zeros. In other words:

boolean ret = NumberUtils.isNumber("0.4790");

On 3.1, ret was true. In 3.3.1, ret is false.

Guessing that LANG-972 is related... comment in the code states:

// leading 0, but not hex, must be octal

This is clearly a case where leading 0 means neither hex nor octal.

Issue Links

• is broken by: LANG-971 NumberUtils#isNumber(String) fails to reject invalid Octal numbers
• is related to: LANG-997 NumberUtil#isNumber() returns false for "012345678" but not for "12345678"
• is related to: LANG-1252 NumberUtils.isNumber and NumberUtils.createNumber resolve inconsistently
• relates to: LANG-1040 Javadoc for NumberUtils.isNumber() are not clear enough
• relates to: LANG-1252 NumberUtils.isNumber and NumberUtils.createNumber resolve inconsistently