最流行的java 工具类

org.apache.commons.io.IOUtils

closeQuietly ( )
toString ( )
copy ( )
toByteArray ( )
write ( )
toInputStream ( )
readLines ( )
copyLarge ( )
lineIterator ( )
readFully ( )

org.apache.commons.io.FileUtils

deleteDirectory ( )
readFileToString ( )
deleteQuietly ( )
copyFile ( )
writeStringToFile ( )
forceMkdir ( )
write ( )
listFiles ( )
copyDirectory ( )
forceDelete ( )

org.apache.commons.lang.StringUtils

isBlank ( )
isNotBlank ( )
isEmpty ( )
isNotEmpty ( )
equals ( )
join ( )
split ( )
EMPTY
trimToNull ( )
replace ( )

org.apache.commons.io.FilenameUtils

getExtension ( )
getBaseName ( )
getName ( )
concat ( )
removeExtension ( )
normalize ( )
wildcardMatch ( )
separatorsToUnix ( )
getFullPath ( )
isExtension ( )

org.springframework.util.StringUtils

hasText ( )
hasLength ( )
isEmpty ( )
commaDelimitedListToStringArray ( )
collectionToDelimitedString ( )
replace ( )
delimitedListToStringArray ( )
uncapitalize ( )
collectionToCommaDelimitedString ( )
tokenizeToStringArray ( )

org.apache.commons.lang.ArrayUtils

contains ( )
addAll ( )
clone ( )
isEmpty ( )
add ( )
EMPTY_BYTE_ARRAY
subarray ( )
indexOf ( )
isEquals ( )
toObject ( )

org.apache.commons.lang.StringEscapeUtils

escapeHtml ( )
unescapeHtml ( )
escapeXml ( )
escapeSql ( )
unescapeJava ( )
escapeJava ( )
escapeJavaScript ( )
unescapeXml ( )
unescapeJavaScript ( )

org.apache.commons.codec.digest.DigestUtils

md5Hex ( )
shaHex ( )
sha256Hex ( )
sha1Hex ( )
sha ( )
md5 ( )
sha512Hex ( )
sha1 ( )

org.apache.commons.collections.CollectionUtils

isEmpty ( )
isNotEmpty ( )
select ( )
transform ( )
filter ( )
find ( )
collect ( )
forAllDo ( )
addAll ( )
isEqualCollection ( )

Joda-Time日期处理类

DateTime
LocalTime