Apache-Commons-工具類介紹及簡(jiǎn)單使用

組件功能介紹BeanUtils提供了對(duì)于JavaBean進(jìn)行各種操作，克隆對(duì)象,屬性等等.BetwixtXML與Java對(duì)象之間相互轉(zhuǎn)換.Codec處理常用的編碼方法的工具類包

例如DES、SHA1、MD5、Base64等.Collectionsjava集合框架操作.Compressjava提供文件打包壓縮類庫(kù).Configuration一個(gè)java應(yīng)用程序的配置管理類庫(kù).DBCP提供數(shù)據(jù)庫(kù)連接池服務(wù).DbUtils提供對(duì)jdbc

的操作封裝來(lái)簡(jiǎn)化數(shù)據(jù)查詢和記錄讀取操作.Emailjava發(fā)送郵件對(duì)javamail的封裝.FileUpload提供文件上傳功能.HttpClien提供HTTP客戶端與服務(wù)器的各種通訊操作.現(xiàn)在已改成HttpComponentsIOio工具的封裝.LangJava基本對(duì)象方法的工具類包如：StringUtils,ArrayUtils等等.Logging提供的是一個(gè)Java的日志接口.Validator提供了客戶端和服務(wù)器端的數(shù)據(jù)驗(yàn)證框架.1、BeanUtils

提供了對(duì)于JavaBean進(jìn)行各種操作，比如對(duì)象,屬性復(fù)制等等。[java]

\o"viewplain"viewplain\o"copy"copy//1、

克隆對(duì)象

//

新創(chuàng)建一個(gè)普通Java

Bean，用來(lái)作為被克隆的對(duì)象

public

class

Person

{

private

String

name

=

"";

private

String

email

=

"";

private

int

age;

//省略

set,get方法

}

//

再創(chuàng)建一個(gè)Test類，其中在main方法中代碼如下：

import

java.lang.reflect.InvocationTargetException;

import

java.util.HashMap;

import

java.util.Map;

import

mons.beanutils.BeanUtils;

import

mons.beanutils.ConvertUtils;

public

class

Test

{

/**

*

@param

args

*/

public

static

void

main(String[]

args)

{

Person

person

=

new

Person();

person.setName("tom");

person.setAge(21);

try

{

//克隆

Person

person2

=

(Person)BeanUtils.cloneBean(person);

System.out.println(person2.getName()+">>"+person2.getAge());

}

catch

(IllegalAccessException

e)

{

e.printStackTrace();

}

catch

(InstantiationException

e)

{

e.printStackTrace();

}

catch

(InvocationTargetException

e)

{

e.printStackTrace();

}

catch

(NoSuchMethodException

e)

{

e.printStackTrace();

}

}

}

//

原理也是通過(guò)Java的反射機(jī)制來(lái)做的。

//

2、

將一個(gè)Map對(duì)象轉(zhuǎn)化為一個(gè)Bean

//

這個(gè)Map對(duì)象的key必須與Bean的屬性相對(duì)應(yīng)。

Map

map

=

new

HashMap();

map.put("name","tom");

map.put("email","tom@");

map.put("age","21");

//將map轉(zhuǎn)化為一個(gè)Person對(duì)象

Person

person

=

new

Person();

BeanUtils.populate(person,map);

//

通過(guò)上面的一行代碼，此時(shí)person的屬性就已經(jīng)具有了上面所賦的值了。

//

將一個(gè)Bean轉(zhuǎn)化為一個(gè)Map對(duì)象了，如下：

Map

map

=

BeanUtils.describe(person)

2、Betwixt

XML與Java對(duì)象之間相互轉(zhuǎn)換。[java]

\o"viewplain"viewplain\o"copy"copy//1、

將JavaBean轉(zhuǎn)為XML內(nèi)容

//

新創(chuàng)建一個(gè)Person類

public

class

Person{

private

String

name;

private

int

age;

/**

Need

to

allow

bean

to

be

created

via

reflection

*/

public

PersonBean()

{

}

public

PersonBean(String

name,

int

age)

{

=

name;

this.age

=

age;

}

//省略set,

get方法

public

String

toString()

{

return

"PersonBean[name='"

+

name

+

"',age='"

+

age

+

"']";

}

}

//再創(chuàng)建一個(gè)WriteApp類：

import

java.io.StringWriter;

import

mons.betwixt.io.BeanWriter;

public

class

WriteApp

{

/**

*

創(chuàng)建一個(gè)例子Bean，并將它轉(zhuǎn)化為XML.

*/

public

static

final

void

main(String

[]

args)

throws

Exception

{

//

先創(chuàng)建一個(gè)StringWriter，我們將把它寫入為一個(gè)字符串

StringWriter

outputWriter

=

new

StringWriter();

//

Betwixt在這里僅僅是將Bean寫入為一個(gè)片斷

//

所以如果要想完整的XML內(nèi)容，我們應(yīng)該寫入頭格式

outputWriter.write(“<?xml

version=’1.0′

encoding=’UTF-8′

?>\n”);

//

創(chuàng)建一個(gè)BeanWriter，其將寫入到我們預(yù)備的stream中

BeanWriter

beanWriter

=

new

BeanWriter(outputWriter);

//

配置betwixt

//

更多詳情請(qǐng)參考java

docs

或最新的文檔

beanWriter.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);

beanWriter.getBindingConfiguration().setMapIDs(false);

beanWriter.enablePrettyPrint();

//

如果這個(gè)地方不傳入XML的根節(jié)點(diǎn)名，Betwixt將自己猜測(cè)是什么

//

但是讓我們將例子Bean名作為根節(jié)點(diǎn)吧

beanWriter.write(“person”,

new

PersonBean(“John

Smith”,

21));

//輸出結(jié)果

System.out.println(outputWriter.toString());

//

Betwixt寫的是片斷而不是一個(gè)文檔，所以不要自動(dòng)的關(guān)閉掉writers或者streams，

//但這里僅僅是一個(gè)例子，不會(huì)做更多事情，所以可以關(guān)掉

outputWriter.close();

}

}

//2、

將XML轉(zhuǎn)化為JavaBean

import

java.io.StringReader;

import

mons.betwixt.io.BeanReader;

public

class

ReadApp

{

public

static

final

void

main(String

args[])

throws

Exception{

//

先創(chuàng)建一個(gè)XML，由于這里僅是作為例子，所以我們硬編碼了一段XML內(nèi)容

StringReader

xmlReader

=

new

StringReader(

"<?xml

version=’1.0′

encoding=’UTF-8′

?>

<person><age>25</age><name>James

Smith</name></person>");

//創(chuàng)建BeanReader

BeanReader

beanReader

=

new

BeanReader();

//配置reader

beanReader.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);

beanReader.getBindingConfiguration().setMapIDs(false);

//注冊(cè)beans，以便betwixt知道XML將要被轉(zhuǎn)化為一個(gè)什么Bean

beanReader.registerBeanClass("person",

PersonBean.class);

//現(xiàn)在我們對(duì)XML進(jìn)行解析

PersonBean

person

=

(PersonBean)

beanReader.parse(xmlReader);

//輸出結(jié)果

System.out.println(person);

}

}

3、Codec

提供了一些公共的編解碼實(shí)現(xiàn)，比如Base64,Hex,MD5,PhoneticandURLs等等。[java]

\o"viewplain"viewplain\o"copy"copy//Base64編解碼

private

static

String

encodeTest(String

str){

Base64

base64

=

new

Base64();

try

{

str

=

base64.encodeToString(str.getBytes("UTF-8"));

}

catch

(UnsupportedEncodingException

e)

{

e.printStackTrace();

}

System.out.println("Base64

編碼后："+str);

return

str;

}

private

static

void

decodeTest(String

str){

Base64

base64

=

new

Base64();

//str

=

Arrays.toString(Base64.decodeBase64(str));

str

=

new

String(Base64.decodeBase64(str));

System.out.println("Base64

解碼后："+str);

}

4、Collections

對(duì)java.util的擴(kuò)展封裝，處理數(shù)據(jù)還是挺靈活的。mons.collections–CommonsCollections自定義的一組公用的接口和工具類mons.collections.bag–

實(shí)現(xiàn)Bag接口的一組類mons.collections.bidimap–

實(shí)現(xiàn)BidiMap系列接口的一組類mons.collections.buffer–

實(shí)現(xiàn)Buffer接口的一組類mons.collections.collection–

實(shí)現(xiàn)java.util.Collection接口的一組類parators–

實(shí)現(xiàn)java.util.Comparator接口的一組類mons.collections.functors–CommonsCollections自定義的一組功能類mons.collections.iterators–

實(shí)現(xiàn)java.util.Iterator接口的一組類mons.collections.keyvalue–

實(shí)現(xiàn)集合和鍵/值映射相關(guān)的一組類mons.collections.list–

實(shí)現(xiàn)java.util.List接口的一組類mons.collections.map–

實(shí)現(xiàn)Map系列接口的一組類mons.collections.set–

實(shí)現(xiàn)Set系列接口的一組類[java]

\o"viewplain"viewplain\o"copy"copy/**

*

得到集合里按順序存放的key之后的某一Key

*/

OrderedMap

map

=

new

LinkedMap();

map.put("FIVE",

"5");

map.put("SIX",

"6");

map.put("SEVEN",

"7");

map.firstKey();

//

returns

"FIVE"

map.nextKey("FIVE");

//

returns

"SIX"

map.nextKey("SIX");

//

returns

"SEVEN"

/**

*

通過(guò)key得到value

*

通過(guò)value得到key

*

將map里的key和value對(duì)調(diào)

*/

BidiMap

bidi

=

new

TreeBidiMap();

bidi.put("SIX",

"6");

bidi.get("SIX");

//

returns

"6"

bidi.getKey("6");

//

returns

"SIX"

//

bidi.removeValue("6");

//

removes

the

mapping

BidiMap

inverse

=

bidi.inverseBidiMap();

//

returns

a

map

with

keys

and

values

swapped

System.out.println(inverse);

/**

*

得到兩個(gè)集合中相同的元素

*/

List<String>

list1

=

new

ArrayList<String>();

list1.add("1");

list1.add("2");

list1.add("3");

List<String>

list2

=

new

ArrayList<String>();

list2.add("2");

list2.add("3");

list2.add("5");

Collection

c

=

CollectionUtils.retainAll(list1,

list2);

System.out.println(c);

5、Compress

commonscompress中的打包、壓縮類庫(kù)。

[java]

\o"viewplain"viewplain\o"copy"copy//創(chuàng)建壓縮對(duì)象

ZipArchiveEntry

entry

=

new

ZipArchiveEntry("CompressTest");

//要壓縮的文件

File

f=new

File("e:\\test.pdf");

FileInputStream

fis=new

FileInputStream(f);

//輸出的對(duì)象

壓縮的文件

ZipArchiveOutputStream

zipOutput=new

ZipArchiveOutputStream(new

File("e:\\test.zip"));

zipOutput.putArchiveEntry(entry);

int

i=0,j;

while((j=fis.read())

!=

-1)

{

zipOutput.write(j);

i++;

System.out.println(i);

}

zipOutput.closeArchiveEntry();

zipOutput.close();

fis.close();

6、Configuration

用來(lái)幫助處理配置文件的，支持很多種存儲(chǔ)方式。

1.Propertiesfiles

2.XMLdocuments

3.Propertylistfiles(.plist)

4.JNDI

5.JDBCDatasource

6.Systemproperties

7.Appletparameters

8.Servletparameters[java]

\o"viewplain"viewplain\o"copy"copy//舉一個(gè)Properties的簡(jiǎn)單例子

#

perties

colors.background

=

#FFFFFF

colors.foreground

=

#000080

window.width

=

500

window.height

=

300

PropertiesConfiguration

config

=

new

PropertiesConfiguration("perties");

config.setProperty("colors.background",

"#000000);

config.save();

config.save("perties);//save

a

copy

Integer

integer

=

config.getInteger("window.width");

7、DBCP

(DatabaseConnectionPool)是一個(gè)依賴Jakartacommons-pool對(duì)象池機(jī)制的數(shù)據(jù)庫(kù)連接池,Tomcat的數(shù)據(jù)源使用的就是DBCP。[java]

\o"viewplain"viewplain\o"copy"copyimport

javax.sql.DataSource;

import

java.sql.Connection;

import

java.sql.Statement;

import

java.sql.ResultSet;

import

java.sql.SQLException;

import

mons.pool.ObjectPool;

import

mons.pool.impl.GenericObjectPool;

import

mons.dbcp.ConnectionFactory;

import

mons.dbcp.PoolingDataSource;

import

mons.dbcp.PoolableConnectionFactory;

import

mons.dbcp.DriverManagerConnectionFactory;

//官方示例

public

class

PoolingDataSources

{

public

static

void

main(String[]

args)

{

System.out.println("加載jdbc驅(qū)動(dòng)");

try

{

Class.forName("oracle.jdbc.driver.OracleDriver");

}

catch

(ClassNotFoundException

e)

{

e.printStackTrace();

}

System.out.println("Done.");

//

System.out.println("設(shè)置數(shù)據(jù)源");

DataSource

dataSource

=

setupDataSource("jdbc:oracle:thin:@localhost:1521:test");

System.out.println("Done.");

//

Connection

conn

=

null;

Statement

stmt

=

null;

ResultSet

rset

=

null;

try

{

System.out.println("Creating

connection.");

conn

=

dataSource.getConnection();

System.out.println("Creating

statement.");

stmt

=

conn.createStatement();

System.out.println("Executing

statement.");

rset

=

stmt.executeQuery("select

*

from

person");

System.out.println("Results:");

int

numcols

=

rset.getMetaData().getColumnCount();

while(rset.next())

{

for(int

i=0;i<=numcols;i++)

{

System.out.print("\t"

+

rset.getString(i));

}

System.out.println("");

}

}

catch(SQLException

e)

{

e.printStackTrace();

}

finally

{

try

{

if

(rset

!=

null)

rset.close();

}

catch(Exception

e)

{

}

try

{

if

(stmt

!=

null)

stmt.close();

}

catch(Exception

e)

{

}

try

{

if

(conn

!=

null)

conn.close();

}

catch(Exception

e)

{

}

}

}

public

static

DataSource

setupDataSource(String

connectURI)

{

//設(shè)置連接地址

ConnectionFactory

connectionFactory

=

new

DriverManagerConnectionFactory(

connectURI,

null);

//

創(chuàng)建連接工廠

PoolableConnectionFactory

poolableConnectionFactory

=

new

PoolableConnectionFactory(

connectionFactory);

//獲取GenericObjectPool

連接的實(shí)例

ObjectPool

connectionPool

=

new

GenericObjectPool(

poolableConnectionFactory);

//

創(chuàng)建

PoolingDriver

PoolingDataSource

dataSource

=

new

PoolingDataSource(connectionPool);

return

dataSource;

}

}

8、DbUtils

Apache組織提供的一個(gè)資源JDBC工具類庫(kù)，它是對(duì)JDBC的簡(jiǎn)單封裝，對(duì)傳統(tǒng)操作數(shù)據(jù)庫(kù)的類進(jìn)行二次封裝，可以把結(jié)果集轉(zhuǎn)化成List。，同時(shí)也不影響程序的性能。DbUtils類：?jiǎn)?dòng)類

ResultSetHandler接口：轉(zhuǎn)換類型接口

MapListHandler類：實(shí)現(xiàn)類，把記錄轉(zhuǎn)化成List

BeanListHandler類：實(shí)現(xiàn)類，把記錄轉(zhuǎn)化成List，使記錄為JavaBean類型的對(duì)象

QreryRunner類：執(zhí)行SQL語(yǔ)句的類[java]

\o"viewplain"viewplain\o"copy"copyimport

mons.dbutils.DbUtils;

import

mons.dbutils.QueryRunner;

import

mons.dbutils.handlers.BeanListHandler;

import

java.sql.Connection;

import

java.sql.DriverManager;

import

java.sql.SQLException;

import

java.util.List;

//轉(zhuǎn)換成list

public

class

BeanLists

{

public

static

void

main(String[]

args)

{

Connection

conn

=

null;

String

url

=

"jdbc:mysql://localhost:3306/ptest";

String

jdbcDriver

=

"com.mysql.jdbc.Driver";

String

user

=

"root";

String

password

=

"ptest";

DbUtils.loadDriver(jdbcDriver);

try

{

conn

=

DriverManager.getConnection(url,

user,

password);

QueryRunner

qr

=

new

QueryRunner();

List

results

=

(List)

qr.query(conn,

"select

id,name

from

person",

new

BeanListHandler(Person.class));

for

(int

i

=

0;

i

<

results.size();

i++)

{

Person

p

=

(Person)

results.get(i);

System.out.println("id:"

+

p.getId()

+

",name:"

+

p.getName());

}

}

catch

(SQLException

e)

{

e.printStackTrace();

}

finally

{

DbUtils.closeQuietly(conn);

}

}

}

public

class

Person{

private

Integer

id;

private

String

name;

//省略set,

get方法

}

import

mons.dbutils.DbUtils;

import

mons.dbutils.QueryRunner;

import

mons.dbutils.handlers.MapListHandler;

import

java.sql.Connection;

import

java.sql.DriverManager;

import

java.sql.SQLException;

import

java.util.List;

import

java.util.Map;

//轉(zhuǎn)換成map

public

class

MapLists

{

public

static

void

main(String[]

args)

{

Connection

conn

=

null;

String

url

=

"jdbc:mysql://localhost:3306/ptest";

String

jdbcDriver

=

"com.mysql.jdbc.Driver";

String

user

=

"root";

String

password

=

"ptest";

DbUtils.loadDriver(jdbcDriver);

try

{

conn

=

DriverManager.getConnection(url,

user,

password);

QueryRunner

qr

=

new

QueryRunner();

List

results

=

(List)

qr.query(conn,

"select

id,name

from

person",

new

MapListHandler());

for

(int

i

=

0;

i

<

results.size();

i++)

{

Map

map

=

(Map)

results.get(i);

System.out.println("id:"

+

map.get("id")

+

",name:"

+

map.get("name"));

}

}

catch

(SQLException

e)

{

e.printStackTrace();

}

finally

{

DbUtils.closeQuietly(conn);

}

}

}

9、Email

提供的一個(gè)開源的API，是對(duì)javamail的封裝。[java]

\o"viewplain"viewplain\o"copy"copy//用commons

email發(fā)送郵件

public

static

void

main(String

args[]){

Email

email

=

new

SimpleEmail();

email.setHostName("");

email.setSmtpPort(465);

email.setAuthenticator(new

DefaultAuthenticator("username",

"password"));

email.setSSLOnConnect(true);

email.setFrom("user@");

email.setSubject("TestMail");

email.setMsg("This

is

a

test

mail

...

:-)");

email.addTo("foo@");

email.send();

}

10、FileUpload

javaweb文件上傳功能。[java]

\o"viewplain"viewplain\o"copy"copy//官方示例：

//*

檢查請(qǐng)求是否含有上傳文件

//

Check

that

we

have

a

file

upload

request

boolean

isMultipart

=

ServletFileUpload.isMultipartContent(request);

//現(xiàn)在我們得到了items的列表

//如果你的應(yīng)用近于最簡(jiǎn)單的情況，上面的處理就夠了。但我們有時(shí)候還是需要更多的控制。

//下面提供了幾種控制選擇：

//

Create

a

factory

for

disk-based

file

items

DiskFileItemFactory

factory

=

new

DiskFileItemFactory();

//

Set

factory

constraints

factory.setSizeThreshold(yourMaxMemorySize);

factory.setRepository(yourTempDirectory);

//

Create

a

new

file

upload

handler

ServletFileUpload

upload

=

new

ServletFileUpload(factory);

//

設(shè)置最大上傳大小

upload.setSizeMax(yourMaxRequestSize);

//

解析所有請(qǐng)求

List

/*

FileItem

*/

items

=

upload.parseRequest(request);

//

Create

a

factory

for

disk-based

file

items

DiskFileItemFactory

factory

=

new

DiskFileItemFactory(

yourMaxMemorySize,

yourTempDirectory);

//一旦解析完成，你需要進(jìn)一步處理item的列表。

//

Process

the

uploaded

items

Iterator

iter

=

items.iterator();

while

(iter.hasNext())

{

FileItem

item

=

(FileItem)

iter.next();

if

(item.isFormField())

{

processFormField(item);

}

else

{

processUploadedFile(item);

}

}

//區(qū)分?jǐn)?shù)據(jù)是否為簡(jiǎn)單的表單數(shù)據(jù)，如果是簡(jiǎn)單的數(shù)據(jù)：

//

processFormField

if

(item.isFormField())

{

String

name

=

item.getFieldName();

String

value

=

item.getString();

//...省略步驟

}

//如果是提交的文件：

//

processUploadedFile

if

(!item.isFormField())

{

String

fieldName

=

item.getFieldName();

String

fileName

=

item.getName();

String

contentType

=

item.getContentType();

boolean

isInMemory

=

item.isInMemory();

long

sizeInBytes

=

item.getSize();

//...省略步驟

}

//對(duì)于這些item，我們通常要把它們寫入文件，或轉(zhuǎn)為一個(gè)流

//

Process

a

file

upload

if

(writeToFile)

{

File

uploadedFile

=

new

File(...);

item.write(uploadedFile);

}

else

{

InputStream

uploadedStream

=

item.getInputStream();

//...省略步驟

uploadedStream.close();

}

//或轉(zhuǎn)為字節(jié)數(shù)組保存在內(nèi)存中：

//

Process

a

file

upload

in

memory

byte[]

data

=

item.get();

//...省略步驟

//如果這個(gè)文件真的很大，你可能會(huì)希望向用戶報(bào)告到底傳了多少到服務(wù)端，讓用戶了解上傳的過(guò)程

//Create

a

progress

listener

ProgressListener

progressListener

=

new

ProgressListener(){

public

void

update(long

pBytesRead,

long

pContentLength,

int

pItems)

{

System.out.println("We

are

currently

reading

item

"

+

pItems);

if

(pContentLength

==

-1)

{

System.out.println("So

far,

"

+

pBytesRead

+

"

bytes

have

been

read.");

}

else

{

System.out.println("So

far,

"

+

pBytesRead

+

"

of

"

+

pContentLength

+

"

bytes

have

been

read.");

}

}

};

upload.setProgressListener(progressListener);

11、HttpClient

基于HttpCore實(shí)現(xiàn)的一個(gè)HTTP/1.1兼容的HTTP客戶端，它提供了一系列可重用的客戶端身份驗(yàn)證、HTTP狀態(tài)保持、HTTP連接管理module。[java]

\o"viewplain"viewplain\o"copy"copy//GET方法

import

java.io.IOException;

import

mons.httpclient.*;

import

mons.httpclient.methods.GetMethod;

import

mons.httpclient.params.HttpMethodParams;

public

class

GetSample{

public

static

void

main(String[]

args)

{

//

構(gòu)造HttpClient的實(shí)例

HttpClient

httpClient

=

new

HttpClient();

//

創(chuàng)建GET方法的實(shí)例

GetMethod

getMethod

=

new

GetMethod("");

//

使用系統(tǒng)提供的默認(rèn)的恢復(fù)策略

getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,

new

DefaultHttpMethodRetryHandler());

try

{

//

執(zhí)行g(shù)etMethod

int

statusCode

=

httpClient.executeMethod(getMethod);

if

(statusCode

!=

HttpStatus.SC_OK)

{

System.err.println("Method

failed:

"

+

getMethod.getStatusLine());

}

//

讀取內(nèi)容

byte[]

responseBody

=

getMethod.getResponseBody();

//

處理內(nèi)容

System.out.println(new

String(responseBody));

}

catch

(HttpException

e)

{

//

發(fā)生致命的異常，可能是協(xié)議不對(duì)或者返回的內(nèi)容有問題

System.out.println("Please

check

your

provided

http

address!");

e.printStackTrace();

}

catch

(IOException

e)

{

//

發(fā)生網(wǎng)絡(luò)異常

e.printStackTrace();

}

finally

{

//

釋放連接

getMethod.releaseConnection();

}

}

}

//POST方法

import

java.io.IOException;

import

mons.httpclient.*;

import

mons.httpclient.methods.PostMethod;

import

mons.httpclient.params.HttpMethodParams;

public

class

PostSample{

public

static

void

main(String[]

args)

{

//

構(gòu)造HttpClient的實(shí)例

HttpClient

httpClient

=

new

HttpClient();

//

創(chuàng)建POST方法的實(shí)例

String

url

=

"/";

PostMethod

postMethod

=

new

PostMethod(url);

//

填入各個(gè)表單域的值

NameValuePair[]

data

=

{

new

NameValuePair("id",

"youUserName"),

new

NameValuePair("passwd",

"yourPwd")

};

//

將表單的值放入postMethod中

postMethod.setRequestBody(data);

//

執(zhí)行postMethod

int

statusCode

=

httpClient.executeMethod(postMethod);

//

HttpClient對(duì)于要求接受后繼服務(wù)的請(qǐng)求，象POST和PUT等不能自動(dòng)處理轉(zhuǎn)發(fā)

//

301或者302

if

(statusCode

==

HttpStatus.SC_MOVED_PERMANENTLY

||

statusCode

==

HttpStatus.SC_MOVED_TEMPORARILY)

{

//

從頭中取出轉(zhuǎn)向的地址

Header

locationHeader

=

postMethod.getResponseHeader("location");

String

location

=

null;

if

(locationHeader

!=

null)

{

location

=

locationHeader.getValue();

System.out.println("The

page

was

redirected

to:"

+

location);

}

else

{

System.err.println("Location

field

value

is

null.");

}

return;

}

}

}

12、IO

對(duì)java.io的擴(kuò)展操作文件非常方便。[java]

\o"viewplain"viewplain\o"copy"copy//1．讀取Stream

//標(biāo)準(zhǔn)代碼：

InputStream

in

=

new

URL(

""

).openStream();

try

{

InputStreamReader

inR

=

new

InputStreamReader(

in

);

BufferedReader

buf

=

new

BufferedReader(

inR

);

String

line;

while

(

(

line

=

buf.readLine()

)

!=

null

)

{

System.out.println(

line

);

}

}

finally

{

in.close();

}

//使用IOUtils

InputStream

in

=

new

URL(

""

).openStream();

try

{

System.out.println(

IOUtils.toString(

in

)

);

}

finally

{

IOUtils.closeQuietly(in);

}

//2．讀取文件

File

file

=

new

File("/commons/io/perties");

List

lines

=

FileUtils.readLines(file,

"UTF-8");

//3．察看剩余空間

long

freeSpace

=

FileSystemUtils.freeSpace("C:/");

13、Lang

主要是一些公共的工具集合，比如對(duì)字符、數(shù)組的操作等等。[java]

\o"viewplain"viewplain\o"copy"copy//

1

合并兩個(gè)數(shù)組:

mons.lang.

ArrayUtils

//

有時(shí)我們需要將兩個(gè)數(shù)組合并為一個(gè)數(shù)組，用ArrayUtils就非常方便，示例如下：

private

static

void

testArr()

{

String[]

s1

=

new

String[]

{

"1",

"2",

"3"

};

String[]

s2

=

new

String[]

{

"a",

"b",

"c"

};

String[]

s

=

(String[])

ArrayUtils.addAll(s1,

s2);

for

(int

i

=

0;

i

<

s.length;

i++)

{

System.out.println(s[i]);

}

String

str

=

ArrayUtils.toString(s);

str

=

str.substring(1,

str.length()

-

1);

System.out.println(str

+

">>"

+

str.length());

}

//2

截取從from開始字符串

StringUtils.substringAfter("SELECT

*

FROM

PERSON

",

"from");

//3

判斷該字符串是不是為數(shù)字(0~9)組成，如果是，返回true

但該方法不識(shí)別有小數(shù)點(diǎn)和

請(qǐng)注意。

StringUtils.isNumeric("454534");

//返回true

//4.取得類名

System.out.println(ClassUtils.getShortClassName(Test.class));

//取得其包名

System.out.println(ClassUtils.getPackageName(Test.class));

//5.NumberUtils

System.out.println(NumberUtils.stringToInt("6"));

//6.五位的隨機(jī)字母和數(shù)字

System.out.println(RandomStringUtils.randomAlphanumeric(5));

//7.StringEscapeUtils

System.out.println(StringEscapeUtils.escapeHtml("<html>"));

//輸出結(jié)果為<html>

System.out.println(StringEscapeUtils.escapeJava("String"));

//8.StringUtils,判斷是否是空格字符

System.out.println(StringUtils.isBlank("

"));

//將數(shù)組中的內(nèi)容以,分隔

System.out.println(StringUtils.join(test,","));

//在右邊加下字符,使之總長(zhǎng)度為6

System.out.println(StringUtils.rightPad("abc",

6,

'T'));

//首字母大寫

System.out.println(StringUtils.capitalize("abc"));

//Deletes

all

whitespaces

from

a

String

刪除所有空格

System.out.println(

StringUtils.deleteWhitespace("

ab

c

"));

//判斷是否包含這個(gè)字符

System.out.println(

StringUtils.contains("abc",

"ba"));

//表示左邊兩個(gè)字符

System.out.println(

StringUtils.left("abc",

2));

System.out.println(NumberUtils.stringToInt("33"));

14、Logging

提供的是一個(gè)Java的日志接口,同時(shí)兼顧輕量級(jí)和不依賴于具體的日志實(shí)現(xiàn)工具。[java]

\o"viewplain"viewplain\o"copy"copyimport

mons.logging.Log;

import

mons.logging.LogFactory;

public

class

CommonLogTest

{

private

static

Log

log

=

LogFactory.getLog(CommonLogTest.class);

//日志打印

public

static

void

main(String[]

args)

{

log.error("ERROR");

log.debug("DEBUG");

log.warn("WARN");

("INF