apache-comnons系列之commons-lang3 学习笔记1

apache-comnons系列之commons-lang3 学习笔记1

概述

ClassLoader与System学习笔记

http://blog.csdn.net/undergrowth/article/details/43647379

String、StringBuffer、StringBuilder、Math学习笔记

http://blog.csdn.net/undergrowth/article/details/43676895

ObjectUtils

Operations on {@code Object}.

ArrayUtils

Operations on arrays, primitive arrays (like {@code int[]}) and primitive wrapper arrays (like {@code Integer[]})

StringUtils

Operations on {@link java.lang.String} that are {@code null} safe

NumberUtils

rovides extra functionality for Java Number classes

DateUtils

A suite of utilities surrounding the use of the {@link java.util.Calendar} and {@link java.util.Date} object.

FastDateParser

FastDateParser is a fast and thread-safe version of {@link java.text.SimpleDateFormat}

DateFormatUtils

SystemUtils

ClassUtils

ThreadUtils

RandomUtils

ExceptionUtils

SerializationUtils

测试

org.apache.commons.lang3.ObjectUtilsTest

defaultIfNull

max

cloneIfPossible

identityToString

org.apache.commons.lang3.ArrayUtilsTest

toArray

Create a type-safe generic array

subarray

Produces a new array containing the elements between the start and end indices

System.arraycopy

reverse

Reverses the order of the given array

swap

removeElement

Removes the first occurrence of the specified element from the specified array. All subsequent elements are shifted to the left (subtracts one from their indices). If the array doesn’t contains such an element, no elements are removed from the array.

indexOf

Finds the index of the given value in the array

org.apache.commons.lang3.StringUtilsTest

isEmpty

Checks if a CharSequence is empty (“”) or null.

trim

Removes control characters (char <= 32) from both ends of this String, handling {@code null} by returning {@code null}.

truncate

Truncates a String. This will turn “Now is the time for all good men” into “Now is the time for”.

split

Splits the provided text into an array, separator specified.This is an alternative to using StringTokenizer

join

Joins the elements of the provided {@code Iterator} into a single String containing the provided elements.

replaceAll

Replaces each substring of the text String that matches the given regular expression with the given replacement

org.apache.commons.lang3.math.NumberUtilsTest

toInt

Convert a

String

to an

int

, returning

zero

if the conversion fails

min

Returns the minimum value in an array

compare

ompares two {@code int} values numerically. This is the same functionality as provided in Java 7.

org.apache.commons.lang3.time.DateUtilsTest

isSameDay

Checks if two date objects are on the same day ignoring time.

isSameInstant

This method compares the long millisecond time of the two objects

parseDate

Parses a string representing a date by trying a variety of different parsers.

addYears

Adds a number of years to a date returning a new object.The original {@code Date} is unchanged.

round

Rounds a date, leaving the field specified as the most significant field.

iterator

Constructs an

Iterator

over each day in a date range defined by a focus date and range style.