转载自：https://blog.csdn.net/m0_37989980/article/details/126396868

一、commons-lang3

引入依赖

<dependency>

    <groupId>org.apache.commons</groupId>

    <artifactId>commons-lang3</artifactId>

    <version>3.12.0</version>

</dependency>

StringUtils 字符串工具类

包含判断方法：contains/containsXXX 

字符串替换方法：replace/replaceXXX 

获取子串：substring/substringXXX 

判断方法：

1、isEmpty/isNotEmpty/isBlank/isNotBlank/isNumeric/isWhitespace

2、sartsWith/startsWithAny/endsWith/endsWithIgnoreCase

索引(index)：indexOf/indexOfXXX/tIndexOf/lastIndexOfXXX

处理方法：

    abbreviate 缩短 capitalise 首字母 repeat 重复 left/right/center 左右中间

    removeXXX 移除 trimXXX 去空  reverseXXX 翻转 stripXXX 移除

    defaultXXX 默认 lowerCase/upperCase deleteXXX 删除处理

    splitXXX分解处理 join 拼接

StringEscapeUtils 转义字符串工具类

StringEscapeUtils类可以对html js xml sql 等代码进行转义来防止SQL注入

escapeCsv/unescapeCsv/escapeHtml/unescapeHtml/escapeJava/unescapeJava

escapeJavaScript/unescapeJavaScript/escapeXml/unescapeXml/escapeSql

NumberUtils 数字工具类

创建数字：createXXX  创建Integer,Float,Double,Number,BigDecimal,BigInteger等数字

字符转数字：toXXX     字符串转数字：Byte,Double,Float,Int,Long,Short

判断是否数字：isDigits/isNumber

其他方法：compare,max,min,

ArrayUtils 数组工具类

添加移除:add,addAll，remove,removeElement,

拷贝：clone

判断：contains,isEmpty,isNotEmpty,isEquals,isSameLength,

其他：getLength,indexOf,lastIndexOf,nullToEmpty,reverse,subArray,

转换：toMap,toObject,toPrimitive,toString

RandomUtils 随机数工具类

nextBoolean/nextInt/nextLong/nextFloat/nextDouble

RandomStringUtils 随机字符串工具类

random/randomNumeric/randomAlphabetic/randomAscii

DateUtils 日期工具类

说明：XXX表示milisecends,seconds,minutes,hours,days,weeks,months,years

时间加减：add/addXXX 

时间设置：setXXX 

获取片段：getFragmentInXXX    获取date的1月1日0点0分0秒到指定时间的片段值

判断： isSameDay/isSameInstant/isSameLocalTime

转换： parseDate/parseDateStrictly

取模： ceiling/round/truncate

时间段：iterator   注意rangeStyle=1到4表示周范围以及偏移，5和6表示月偏移

DateFormatUtils时间格式化

格式化：format/formatUTC

DurationFormatUtils时间段格式化

formatDuration/formatDurationHMS/formatDurationISO

formatPeriod/formatPeriodISO

formatDurationWords

StopWatch 秒表

start/stop/suspend/split/resume/reset/unsplit

getSplitTime/getStartTime/getTime/

toSplitString/toString

EnumUtils 枚举工具类

getEnum/getEnumIgnoreCase/getEnumList/getEnumMap

iterator

反射工具类

ClassUtils 类工具

获取： 

    1、类和接口 ：getClass/getAllInterfaces/getAllSuperclasses/getShortClassName

    2、包：getPackageName/getPackageCanonicalName

    3、方法：getPublicMethod

转换：

    1、toClass/convertClassesToClassNames/convertClassNamesToClasses/

    2、primitivesToWrappers/primitiveToWrapper/wrappersToPrimitives/wrapperToPrimitive

判断：isAssignable/isInnerClass

MethodUtils

getAccessibleMethod/getMatchingAccessibleMethod

invokeMethod/invokeStaticMethod/invokeExactMethod/invokeExactStaticMethod

FieldUtils

getField/readField/writeField

getDeclaredField/readDeclaredField/writeDeclaredField

readDeclaredStaticField/readStaticField/writeDeclaredStaticField/writeStaticField

ConstructorUtils

getAccessibleConstructor/getMatchingAccessibleConstructor

invokeConstructor/invokeExactConstructor

ObjectUtils 对象工具类

max/min/toString/identityToString/appendIdentityToString/defaultIfNull

SystemUtils 系统属性工具类

getJavaHome/getJavaIoTmpDir/getJavaVersion/getUserDir/getUserHome/

isJavaAwtHeadless/isJavaVersionAtLeast

SerializationUtils 序列化工具类

clone/deserialize/serialize

LocaleUtils 本地工具类

availableLocaleList/availableLocaleSet

countriesByLanguage

localeLookupList/toLocale/isAvailableLocale/languagesByCountry

二、commons-collecions4

引入依赖

<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-collections4 -->

<dependency>

    <groupId>org.apache.commons</groupId>

    <artifactId>commons-collections4</artifactId>

    <version>4.4</version>

</dependency>

CollectionUtils 集合工具类

添加/删除:addAll/addIgnoreNull/retainAll/removeAll/

获取：

find/get/containsAny/index/size/sizeIsEmpty/select/selectRejected/subtract

typedCollection

判断： 

isEmpty/isNotEmpty/isFull/exists/isEqualCollection/

isSubCollection/isProperSubCollection 

转换： 

collect/transform/transformedCollection/predicatedCollection

unmodifiableCollection/synchronizedCollection 

计算：cardinality/countMatches/maxSize

过滤：filter

集合：intersection/union/disjunction  交集，并集，差集

其他操作：

   reverseArray  翻转  forAllDo 给每个元素执行闭包

   getCardinalityMap 转成Map,key是元素，value是次数

ListUtils-List工具类

判断： isEqualList

集合：intersection/sum/union/retainAll 交集，并集，合集，差集

操作：removeAll/hashCodeForList

子集： typedList/subtract/fixedSizeList

转换处理：synchronizedList/unmodifiableList/predicatedList/transformedList/lazyList

SetUtils-Set集合工具类

判断：isEqualSet

转换处理：

transformedSet/transformedSortedSet/predicatedSet/predicatedSortedSet

unmodifiableSet/synchronizedSet/synchronizedSortedSet

orderedSet/typedSet/typedSortedSet

操作：hashCodeForSet

MapUtils-Map工具类

获取：getObject/getString/getXXX/getXXXValue  获取指定类型值，getXXXValue 如果没有值则默认值

子集：fixedSizeMap/fixedSizeSortedMap/typedMap/typedSortedMap

判断：isEmpty/isNotEmpty

转换：

predicatedMap/predicatedSortedMap/transformedMap/transformedSortedMap/

synchronizedMap/synchronizedSortedMap/

unmodifiableMap/unmodifiableSortedMap/multiValueMap/orderedMap

toMap/toProperties/lazyMap/lazySortedMap

添加移除：safeAddToMap/putAll

其他操作：invertMap/debugPrint/verbosePrint

三、commons-beanutils

引入依赖

<dependency>

    <groupId>commons-beanutils</groupId>

    <artifactId>commons-beanutils</artifactId>

    <version>1.9.4</version>

</dependency>

BeanUtils/BeanUtilsBean

拷贝： cloneBean/copyProperties/copyProperty

获取：getArrayProperty/getSimpleProperty/getProperty

其他操作：setProperty设置属性 populate将Bean设置到Map中  describe将Bean转成Map  

PropertyUtils类

判断：isReadable/isWriteable

获取：

getProperty/getSimpleProperty/getPropertyType 

getReadMethod/getWriteMethod/getIndexedProperty/setIndexedProperty

getMappedProperty/setMappedProperty/getNestedProperty/setNestedProperty  

getPropertyDescriptor/getPropertyEditorClass

拷贝和设置：copyProperties/setProperty/setSimpleProperty /clearDescriptors       

四、commons-io

引入依赖

<dependency>

    <groupId>commons-io</groupId>

    <artifactId>commons-io</artifactId>

    <version>2.11.0</version>

</dependency>

FileUtils 文件操作工具类

文件夹操作： 

 copyDirectory/deleteDirectory/cleanDirectory/getTempDirectory/getTempDirectoryPath

 moveDirectory/moveDirectoryToDirectory/moveFileToDirectory/moveToDirectory

 forceMkdir/getUserDirectory/getUserDirectoryPath

文件操作：

touch/copyFile/copyURLToFile/moveFile/deleteQuietly/forceDelete/forceDeleteOnExit

toFile/toFiles/toURLs

isFileNewer/isFileOlder

readLines/readFileToByteArray/readFileToString/lineIterator/openOutputStream

write/writeLines/writeByteArrayToFile/writeStringToFile/openInputStream

其他操作：

    iterateFiles/listFiles/contentEquals/sizeOf/sizeOfDirectory

IOUtils 流操作工具类

读操作：lineIterator/read/readLines

写操作：write/writeLines

转换： toInputStream/toBufferedInputStream/toByteArray/toCharArray/toString

其他操作：copy/copyLarge/contentEquals/skip/skipFully/closeQuietly

FilenameUtils 文件名工具类

获取：

getName/getBaseName/getPrefix/getPrefixLength/getExtension

getPath/getFullPath/getFullPathNoEndSeparator/getPathNoEndSeparator

判断：

isExtension/equals/equalsNormalized/equalsOnSystem

其他操作：

removeExtension/indexOfExtension

separatorsToSystem/separatorsToUnix/separatorsToWindows

indexOfLastSeparator

其他工具类

文件比较器：

    CompositeFileComparator/DefaultFileComparator/DirectoryFileComparator

    ExtensionFileComparator/LastModifiedFileComparator/NameFileComparator

    PathFileComparator/PathFileComparator

文件过滤器：

    AgeFileFilter/AndFileFilter/CanReadFileFilter/CanWriteFileFilter

    DelegateFileFilter/DirectoryFileFilter/EmptyFileFilter/FalseFileFilter/FileFileFilter

    FileFilterUtils/HiddenFileFilter/MagicNumberFileFilter/NameFileFilter/NotFileFilter

    OrFileFilter/PrefixFileFilter/RegexFileFilter/SizeFileFilter/SuffixFileFilter

    TrueFileFilter/WildcardFileFilter/WildcardFilter