在Java中，实用程序类是定义一组执行通用功能的方法的类。
这篇文章展示了最常用的Java实用工具类及其最常用的方法。类列表及其方法列表均按受欢迎程度排序。数据基于从GitHub随机选择的50,000个开源Java项目。
希望您可以通过浏览列表来了解已经提供和流行的功能的一些想法，以使您知道不需要自己实现。这些方法的名称通常指示它们的作用。如果方法名称不够直观，您还可以查看其他开发人员如何在其开源项目中使用它们。
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()
