来自：u012624222的CSDN博客
链接：http://blog.csdn.net/u012624222/article/details/50349847
原文：http://www.programcreek.com/2015/12/top-10-java-utility-classes/
Java中有许多应用类，这些类定义静态方法可以解决很多常见的问题。下面是通过5万个开源项目统计得到的最热门的16个应用类。 类按热门程序排列，类的方法也是按热门程序排序。
浏览这个类可以看看有哪些功能不用再自己写了。 非常有用。
1、org.apache.commons.io.IOUtils
closeQuietly ( )
toString ( )
copy ( )
toByteArray ( )
write ( )
toInputStream ( )
readLines ( )
copyLarge ( )
lineIterator ( )
readFully ( )
2、org.apache.commons.io.FileUtils
deleteDirectory ( )
readFileToString ( )
deleteQuietly ( )
copyFile ( )
writeStringToFile ( )
forceMkdir ( )
write ( )
listFiles ( )
copyDirectory ( )
forceDelete ( )
3、 org.apache.commons.lang.StringUtils
isBlank ( )
isNotBlank ( )
isEmpty ( )
isNotEmpty ( )
equals ( )
join ( )
split ( )
EMPTY
trimToNull ( )
replace ( )
4、org.apache.http.util.EntityUtils
toString ( )
consume ( )
toByteArray ( )
consumeQuietly ( )
getContentCharSet ( )
5、org.apache.commons.lang3.StringUtils
isBlank ( )
isNotBlank ( )
isEmpty ( )
isNotEmpty ( )
join ( )
equals ( )
split ( )
EMPTY
replace ( )
capitalize ( )
6、org.apache.commons.io.FilenameUtils
getExtension ( )
getBaseName ( )
getName ( )
concat ( )
removeExtension ( )
normalize ( )
wildcardMatch ( )
separatorsToUnix ( )
getFullPath ( )
isExtension ( )
7、org.springframework.util.StringUtils
hasText ( )
hasLength ( )
isEmpty ( )
commaDelimitedListToStringArray ( )
collectionToDelimitedString ( )
replace ( )
delimitedListToStringArray ( )
uncapitalize ( )
collectionToCommaDelimitedString ( )
tokenizeToStringArray ( )
8、org.apache.commons.lang.ArrayUtils
contains ( )
addAll ( )
clone ( )
isEmpty ( )
add ( )
EMPTY_BYTE_ARRAY
subarray ( )
indexOf ( )
isEquals ( )
toObject ( )
9、org.apache.commons.lang.StringEscapeUtils
escapeHtml ( )
unescapeHtml ( )
escapeXml ( )
escapeSql ( )
unescapeJava ( )
escapeJava ( )
escapeJavaScript ( )
unescapeXml ( )
unescapeJavaScript ( )
10、org.apache.http.client.utils.URLEncodedUtils
format ( )
parse ( )
11、org.apache.commons.codec.digest.DigestUtils
md5Hex ( )
shaHex ( )
sha256Hex ( )
sha1Hex ( )
sha ( )
md5 ( )
sha512Hex ( )
sha1 ( )
12、org.apache.commons.collections.CollectionUtils
isEmpty ( )
isNotEmpty ( )
select ( )
transform ( )
filter ( )
find ( )
collect ( )
forAllDo ( )
addAll ( )
isEqualCollection ( )
13、org.apache.commons.lang3.ArrayUtils
contains ( )
isEmpty ( )
isNotEmpty ( )
add ( )
clone ( )
addAll ( )
subarray ( )
indexOf ( )
EMPTY_OBJECT_ARRAY
EMPTY_STRING_ARRAY
14、org.apache.commons.beanutils.PropertyUtils
getProperty ( )
setProperty ( )
getPropertyDescriptors ( )
isReadable ( )
copyProperties ( )
getPropertyDescriptor ( )
getSimpleProperty ( )
isWriteable ( )
setSimpleProperty ( )
getPropertyType ( )
15、org.apache.commons.lang3.StringEscapeUtils
unescapeHtml4 ( )
escapeHtml4 ( )
escapeXml ( )
unescapeXml ( )
escapeJava ( )
escapeEcmaScript ( )
unescapeJava ( )
escapeJson ( )
escapeXml10 ( )
16、org.apache.commons.beanutils.BeanUtils
copyProperties ( )
getProperty ( )
setProperty ( )
describe ( )
populate ( )
copyProperty ( )
cloneBean ( )