Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 SwQOFE/Dv~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $Jt8d|UP
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 ~MD><w>
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 @)8NI[=6O
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分页支持类: 8Na}Wp;|Gi
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java代码: X@G[=Rs
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package com.javaeye.common.util; UeC 81*XZ
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import java.util.List; N>h]mX6
1j8 /4:
publicclass PaginationSupport { VN1#8{
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publicfinalstaticint PAGESIZE = 30; nT(!HDH
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privateint pageSize = PAGESIZE; PP~CZ2Fze
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privateList items; oKZ[0(4<
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privateint totalCount; UEk|8yq
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privateint[] indexes = newint[0]; ^!XU+e+:0
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privateint startIndex = 0; w`2_6[,9
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public PaginationSupport(List items, int ~r7DEy|+
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totalCount){ 4"`=hu Q
setPageSize(PAGESIZE); GA}hp%
setTotalCount(totalCount); kjQIagw
setItems(items); })Ix.!p
setStartIndex(0); eU<]h>2
} w/)e2CH
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public PaginationSupport(List items, int !^rITiy
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totalCount, int startIndex){ :"h
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setPageSize(PAGESIZE); m(Pz7U.Q
setTotalCount(totalCount); ~M|NzK_9
setItems(items); `K@5_db\
setStartIndex(startIndex); >c~9wv
} -sruxF
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public PaginationSupport(List items, int j58Dki->.
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totalCount, int pageSize, int startIndex){ 6T5A31 Q
setPageSize(pageSize); {3_F fsg`
setTotalCount(totalCount); j@!BOL~?
setItems(items); c9>8IW
setStartIndex(startIndex); x|P<F 2L
} |sDG>Zq?
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publicList getItems(){ w%!k?t,*]
return items; .je~qo)
} 5+#?7J1
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publicvoid setItems(List items){ "1=.5:yG
this.items = items; S.?\>iH[
} |>m# m*{S
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publicint getPageSize(){ rVc
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return pageSize; NG4eEnic!a
} QqT6P`0u
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publicvoid setPageSize(int pageSize){ Hj-<{#,
this.pageSize = pageSize; ;RTrRh0v
}
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publicint getTotalCount(){ TWD|1
di0
return totalCount; 3<Pyr-z h
} bRY4yT
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publicvoid setTotalCount(int totalCount){ `i_L?C7
if(totalCount > 0){ /I`!iK
this.totalCount = totalCount; -hJ>wGI
int count = totalCount / HquB*=^xh
nATfmUN
L
pageSize; \I`=JKYT
if(totalCount % pageSize > 0) 6>P
count++; 8{U]ATx'(
indexes = newint[count]; !Barc,kA
for(int i = 0; i < count; i++){ C$]%1<-Iv]
indexes = pageSize * W6!4Qyn
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} &d &oP
}else{ {O3oUE+
this.totalCount = 0; yScov)dp(
} F"HI>t)>
} 0'`8HP
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publicint[] getIndexes(){ '"G
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return indexes; +h9l%Pz
} ""U?#<}GD
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publicvoid setIndexes(int[] indexes){ 8=zM~v)
this.indexes = indexes; p.W*j^';Q
} ^7^bA
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publicint getStartIndex(){ &>wce5uV
return startIndex; Jr*S2z<*
} U{:(j5m
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publicvoid setStartIndex(int startIndex){ qyG636i
if(totalCount <= 0) e8ig[:B>+
this.startIndex = 0; u^4 "96aXJ
elseif(startIndex >= totalCount) spoWdRM2
this.startIndex = indexes (fI&("; t
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[indexes.length - 1]; U!-+v:SF
elseif(startIndex < 0) "3>*i!i
this.startIndex = 0; ?H86Wbz
else{ E[htB><
this.startIndex = indexes %?9r (&
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[startIndex / pageSize]; {dr&46$p
} zL!~,B8C
} (gJ
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publicint getNextIndex(){ F>oxnhp6
int nextIndex = getStartIndex() + 4>wIF }\
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pageSize; h9OL%n 7m'
if(nextIndex >= totalCount) Gk]qE]hi
return getStartIndex(); E(4lu%
else ^*UfCoj9Z
return nextIndex; ?GD?J(S
} ]OCJ~Zw
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publicint getPreviousIndex(){ Hpo?|;3D5
int previousIndex = getStartIndex() - 6x zR*~7
K7R])*B.~
pageSize; TWR#MVMI
if(previousIndex < 0) zl0:U2x7
return0; {@F["YPxy
else 5`{;hFl
return previousIndex; rj f=qh5s
} 2;(iTPz +
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} )D-.7m.v]
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抽象业务类 1S.e5{
java代码: "drh+oo.
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/** z hm!sMlO
* Created on 2005-7-12 MfpWow-#{
*/ C.e|VzQa
package com.javaeye.common.business; %LZM5Z^
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import java.io.Serializable; iYQy#kO
import java.util.List; YU0HySP:
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import org.hibernate.Criteria; HF=C8ZtlL
import org.hibernate.HibernateException; 1*,~ 1!>
import org.hibernate.Session; EKS<s82hF&
import org.hibernate.criterion.DetachedCriteria; ~TK^aM
import org.hibernate.criterion.Projections; l:Xf(TLa
import OVo
IEr`6|X
org.springframework.orm.hibernate3.HibernateCallback; ysT!^-&p
import c:_i)":
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org.springframework.orm.hibernate3.support.HibernateDaoS y#Sw>-zRq
0B:{4Lsn&
upport; |3lAye,t)a
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import com.javaeye.common.util.PaginationSupport; |b@A:8ss
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public abstract class AbstractManager extends .VEfd4+ni{
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}{
HibernateDaoSupport { e%0#"6}
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privateboolean cacheQueries = false; o[r6sz:
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privateString queryCacheRegion; `xAJy5
h \cK
publicvoid setCacheQueries(boolean h)RM9813<
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cacheQueries){ }fMFQA)
this.cacheQueries = cacheQueries; dv}R]f'
} Bv]wHPun
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publicvoid setQueryCacheRegion(String G`lhvpifG
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queryCacheRegion){ _$_CR\$
this.queryCacheRegion = FT<*
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queryCacheRegion; |nZB/YZt
} 5*za]
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publicvoid save(finalObject entity){ J0mCWtx&
getHibernateTemplate().save(entity); n.UM+2G
} >#n-4NZ;p9
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publicvoid persist(finalObject entity){ G:ngio]G0
getHibernateTemplate().save(entity); b%t9a\ 0V
} 1% %Tm"
@!NHeH=pR
publicvoid update(finalObject entity){ kL2sJX+
getHibernateTemplate().update(entity); :+^llz
} HZ4
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publicvoid delete(finalObject entity){ OL"5A18;M
getHibernateTemplate().delete(entity); `rJ ~*7-
} J` --O(8Ml
M@[gT?mv1
publicObject load(finalClass entity, ]@T `qR
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finalSerializable id){ Guc^gq}
return getHibernateTemplate().load G'C^C[_W
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(entity, id); N!&VBx^z
} :@A;!'zpL
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publicObject get(finalClass entity, TmAb!
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finalSerializable id){ U.h PC3
return getHibernateTemplate().get !7*/lG
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(entity, id); ~'\u:Imuo
} 3?CpylCO
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publicList findAll(finalClass entity){ _u5U> w
return getHibernateTemplate().find("from F>R)~;Ja
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" + entity.getName()); :!FwF65
} Fpwh.R:yV
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publicList findByNamedQuery(finalString h;[Ncj]
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namedQuery){ 640V&<+v
return getHibernateTemplate TBYL~QQD\C
cSDCNc*%
().findByNamedQuery(namedQuery); Z}S tA0F_
} ,OAWGFKOp
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publicList findByNamedQuery(finalString query, _Hj,;Z
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finalObject parameter){ %=eD)p7l-
return getHibernateTemplate hKeh9 Bt
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().findByNamedQuery(query, parameter); v]S8!wU
} bZfJG^3
%,RU)}
publicList findByNamedQuery(finalString query, 3_/d=ZI\
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finalObject[] parameters){ X/7 49"23
return getHibernateTemplate ZA@"uqa 6b
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().findByNamedQuery(query, parameters); vLS6Gb't
} dBn.DU*B
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publicList find(finalString query){ Xxw.{2Ji!q
return getHibernateTemplate().find :\RB ^3;
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(query); P .( X]+
} [wYQP6Cyy
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publicList find(finalString query, finalObject NebZGD2K
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parameter){ ,r4af<
return getHibernateTemplate().find z8MYgn7
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(query, parameter); zf#&3K 'k
} r6G)R+ #
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public PaginationSupport findPageByCriteria Vtri"G8 aB
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(final DetachedCriteria detachedCriteria){ Pw{+7b$
return findPageByCriteria TUr}p aw_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); w+H=Xh4t
} `#U6`[[
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public PaginationSupport findPageByCriteria S0yT%V
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(final DetachedCriteria detachedCriteria, finalint T94$}- 5/)
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startIndex){ wS4wED&a
return findPageByCriteria \3/'#
;'}xD5]
(detachedCriteria, PaginationSupport.PAGESIZE, B;Vl+}R
)=@ XF0
startIndex); R)z|("%ec
} s#3{c@^3
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public PaginationSupport findPageByCriteria A:Z:&(NtE:
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(final DetachedCriteria detachedCriteria, finalint #$E
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pageSize, 3WS %H17
finalint startIndex){ C54)eT6
return(PaginationSupport) _u;
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getHibernateTemplate().execute(new HibernateCallback(){ I%`2RXBt3^
publicObject doInHibernate tB.9Ov*
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(Session session)throws HibernateException { #S)*MT4ke
Criteria criteria = -d]z_
SP@
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detachedCriteria.getExecutableCriteria(session); DS fKUx&
int totalCount = \ZB;K~BV&
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((Integer) criteria.setProjection(Projections.rowCount o hCPNm
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()).uniqueResult()).intValue(); .Pi67Kj,
criteria.setProjection >Ko )Z&j9W
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(null); TXM.,5Dx\
List items = bUNp>H>L
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criteria.setFirstResult(startIndex).setMaxResults * ?K=;$
(ym)q#^
(pageSize).list(); _1~Sj*
PaginationSupport ps = ` {p5SYj
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new PaginationSupport(items, totalCount, pageSize, ]jYM;e
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startIndex); <4Fd~
return ps; B$G8,3 ,:
} pFuQ!7Uk
}, true); $O#h4L_
} Y~6pJNR
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public List findAllByCriteria(final E:ytdaiT
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DetachedCriteria detachedCriteria){ tj0vB]c
return(List) getHibernateTemplate 6yU~^))bx
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().execute(new HibernateCallback(){ V-31x )
publicObject doInHibernate <|4j<U
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(Session session)throws HibernateException { fiZ8s=J
Criteria criteria = >cp9{+#f
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detachedCriteria.getExecutableCriteria(session); ?cJ$=
return criteria.list(); jL# ak V
} *=8)]_=f
}, true); +2?[=g4;}
} ?/\;K1c p
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public int getCountByCriteria(final xl3U
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DetachedCriteria detachedCriteria){ z} %to0W
Integer count = (Integer) 8Xr3q eh+
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getHibernateTemplate().execute(new HibernateCallback(){ ;u%h wlo
publicObject doInHibernate #%5>}$
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(Session session)throws HibernateException { MG6Tk(3S
Criteria criteria = \yqiv"'
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detachedCriteria.getExecutableCriteria(session); cA*%K[9
return {MS&t09Wh
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criteria.setProjection(Projections.rowCount k}/:
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()).uniqueResult(); d09GD[5
} xqr`T0!&
}, true); UaBR;v-.B3
return count.intValue(); 9T]]T Ev4
} \S9z.!7v$
} {`'b+0[;@
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用户在web层构造查询条件detachedCriteria,和可选的 ,iyIF~1~#>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [H&m@*UO
; ^$RG
PaginationSupport的实例ps。 B}Qo8i7
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ps.getItems()得到已分页好的结果集 8c~H![2u
ps.getIndexes()得到分页索引的数组 @EQ{lGpU3
ps.getTotalCount()得到总结果数 23>?3-q
ps.getStartIndex()当前分页索引 B[$e;h*Aw[
ps.getNextIndex()下一页索引 g
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ps.getPreviousIndex()上一页索引 D"hiEz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R[Rs2eS_
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 qGw6Wp~
zh6so.
一下代码重构了。 ~q/`Z)(yc
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我把原本我的做法也提供出来供大家讨论吧: 8_uDxd
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首先,为了实现分页查询,我封装了一个Page类: H$;\TG@,
java代码: ,"/_G
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/*Created on 2005-4-14*/ w 8E,zH
package org.flyware.util.page; 9> |rIw
HG^8&uh]
/** ^O?$}sr
* @author Joa *D'VW{
* D H/1 :H
*/ 5!Guf?i
publicclass Page { s)C.e# xl
=m40{
/** imply if the page has previous page */ qj|GAGrQ2
privateboolean hasPrePage; q\~7z1
D Lu]d$G
/** imply if the page has next page */ b"gYNGgX
privateboolean hasNextPage; B!<I[fvK
>8,BC
/** the number of every page */ <ZocMv9gM
privateint everyPage; \CL`j
r8xH A
/** the total page number */ !b7H
privateint totalPage; ]*@7o^4i
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/** the number of current page */ |9g*rO
privateint currentPage; rUyT5Vf
)yK!EK\
/** the begin index of the records by the current ZpZ~[BtQ
5E%W;$3Pb
query */ ^^[,aBu
privateint beginIndex; l/`Z+];
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/** The default constructor */ Ywni2-)<
public Page(){ 3w-0v"j U
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} )j$Bo{
-H]svOX
/** construct the page by everyPage $Fn# b|e
* @param everyPage 8xNKVj)@
* */ mr;WxxO5
public Page(int everyPage){ H'Po
this.everyPage = everyPage; c"|^Lo.
} cO<x:{`
ZF`ckWT:-N
/** The whole constructor */ -AbA6_j
public Page(boolean hasPrePage, boolean hasNextPage, <sPB|5Ak
Z?b.
PC/
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int everyPage, int totalPage, a{HvrWs?Q
int currentPage, int beginIndex){ u_uC78`p
this.hasPrePage = hasPrePage; _[<I&^%
this.hasNextPage = hasNextPage; }3+(A`9h f
this.everyPage = everyPage; I[R?j?$}>
this.totalPage = totalPage; E{FN sa
this.currentPage = currentPage; y_'8m9Qy)
this.beginIndex = beginIndex; WgY3g1C
} n"Ev25%
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/** RpreW7B_Q*
* @return ]\GGC]:\@
* Returns the beginIndex. ]s u\[?l
*/ ^awl-CG
publicint getBeginIndex(){ Wl*\kQ}U
return beginIndex; Z8:iaP)
} `=.{i}V
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/** jW6@U%[!b
* @param beginIndex wOOPuCw?
* The beginIndex to set. kt@+UK."
*/ t%/5$<!b
publicvoid setBeginIndex(int beginIndex){ :]]amziP&
this.beginIndex = beginIndex; $k!t&G
} Zw }7vD0
ld3,)ZY
/** oc15!M3$
* @return 2;q6~Y,
* Returns the currentPage. D6 M:pIN*
*/ f[X>?{q
publicint getCurrentPage(){ EswM#D9(4
return currentPage; ^x4gUT-Wy
} SmRU!C$A
;A|6&~E0G
/** +xWT)h/
* @param currentPage
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* The currentPage to set. j\W+wnAgk
*/ L-MpdC
publicvoid setCurrentPage(int currentPage){ |#S!qnXB
this.currentPage = currentPage; f+)F-3
} q'W`t>2T
Q@M,:0+cy
/** `a<G7
* @return 9m#`56G`
* Returns the everyPage. yJr' \(
*/ `]fY9ZDKs
publicint getEveryPage(){ :@pmgp
return everyPage; s(zG.7*3n
} Yc9 M6=E^
te:@F]A
/** h'N,oDB)
* @param everyPage ]o_ Ps|
* The everyPage to set. ]A_)&`"Cb
*/ z`/v}'d[X
publicvoid setEveryPage(int everyPage){ ."MBKyg6
this.everyPage = everyPage; ]qrO"X=
} )[/+j"F
ov?>ALRg
/** 6~}=? sX4
* @return &<L+;k~P%
* Returns the hasNextPage. ~
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*/ u[cbRn,W
publicboolean getHasNextPage(){ 4u"O/rt
return hasNextPage; YHE7`\l
} Qs~;?BH&
T6{IuQjXs
/** i8dv|oa
* @param hasNextPage [t0gX dU6
* The hasNextPage to set. ZZ4W?);;
*/ _7 n+j
publicvoid setHasNextPage(boolean hasNextPage){ fa$ Fo(.
this.hasNextPage = hasNextPage; q~a6ES_lA
} &ts!D!Hj
S c@g;+#QU
/**
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* @return }n8,Ga%
* Returns the hasPrePage. `m3C\\9;
*/ c1Dhx,]ad
publicboolean getHasPrePage(){ 1z*] MYU
return hasPrePage; 1z{AzpMZ
} )82x)c<e
n|{x\@VeF
/** |3vQmd !2}
* @param hasPrePage >\MV/!W
* The hasPrePage to set. ;o#dmG
*/ .O~)zMx
publicvoid setHasPrePage(boolean hasPrePage){ (3W<yAM+
this.hasPrePage = hasPrePage; [ UQzCqV
} *-gS u
)=8X[<^i
/** _4.fT
* @return Returns the totalPage. j#o0y5S
* qA&N6`
*/ t R*JM$T
publicint getTotalPage(){ Z~$fTW6g
return totalPage; zX|CW;
} VNaa(Q
tZ4W]od
/** )PR{ia64;<
* @param totalPage Z1*y$=D?3[
* The totalPage to set. E5.)ro=$
*/ qksN {t
publicvoid setTotalPage(int totalPage){ *"4
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this.totalPage = totalPage; ;Q-(tGd
} (%\N-[yZ
]#_,?d
} O
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,HR~oT^
K+PzTGWq^
1 vi<@i,
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 0E{$u
P|c79
个PageUtil,负责对Page对象进行构造: _ 4pBJOJQ6
java代码: CShVJ:u+K\
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par
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/*Created on 2005-4-14*/ %I[(`nb
package org.flyware.util.page; .-fJ\`^mi
k$#
@_
import org.apache.commons.logging.Log; #;>J<>
import org.apache.commons.logging.LogFactory; uB0/H=<H
y~''r%]
/** NSj}?hz
* @author Joa Lab{?!E>U
* ~%(r47n
*/ 61b,+'-
publicclass PageUtil {
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NC|&7qQ
privatestaticfinal Log logger = LogFactory.getLog |$^,e%bE
1u'x|Un
(PageUtil.class); d{I|4h
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/** QV7K~qi
* Use the origin page to create a new page R CnN+b:c
* @param page ,RDxu7iT
* @param totalRecords
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* @return "\]kK@,
*/ `)!)}PXl
publicstatic Page createPage(Page page, int Hk(w\
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totalRecords){ *ofK|r
return createPage(page.getEveryPage(), qqLmjDv
ok2$ p
page.getCurrentPage(), totalRecords); 9^)ochY3
} (Sv 7^}j
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/** R84g<
* the basic page utils not including exception 2-. g>'W
}mk9-7
handler ,m9Nd "6\
* @param everyPage A:0
* @param currentPage L*Xn!d%
* @param totalRecords m},nKsO
* @return page v6;XxBR6
*/ e#)}.
publicstatic Page createPage(int everyPage, int dGrOw)
hQ#'_%:
currentPage, int totalRecords){ {.DI[@.g
everyPage = getEveryPage(everyPage); 45W:b/n\
currentPage = getCurrentPage(currentPage); 7f~DD8 R
int beginIndex = getBeginIndex(everyPage, Vt*Duh+4
t? yMuK
currentPage); l3)(aay!
int totalPage = getTotalPage(everyPage, z@{|Y;s
ko>SnE|w#
totalRecords); 2p8JqZMQb
boolean hasNextPage = hasNextPage(currentPage, G]=U=9ZI
]nEN3RJ
totalPage); l92#F*
boolean hasPrePage = hasPrePage(currentPage); 'w^1re=R
p%G4Js.
returnnew Page(hasPrePage, hasNextPage, ;XZ5r|V}
everyPage, totalPage, TJ
;4QL
currentPage, k;#$Oxa>t=
v$owG-_><
beginIndex); :DR
G=-M
} rX{QgyY&
EAqTXB@XU
privatestaticint getEveryPage(int everyPage){ vFV->/u
return everyPage == 0 ? 10 : everyPage; !c\s)&U7B
} PQlG!
n)8bkcZCp+
privatestaticint getCurrentPage(int currentPage){ -P!vCf^{
t
return currentPage == 0 ? 1 : currentPage; 1W"9u
} Cx}
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privatestaticint getBeginIndex(int everyPage, int WIQt5=-
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currentPage){ H7H'0C
return(currentPage - 1) * everyPage; bv)E>%Yy
} p}}}~ lC/
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privatestaticint getTotalPage(int everyPage, int *;1 G+Q#
\# lh b
totalRecords){ hUxpz:U*
int totalPage = 0; cSnm \f
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if(totalRecords % everyPage == 0) =uYSZR
totalPage = totalRecords / everyPage; GmcxN<
else ZL+{?1&-
totalPage = totalRecords / everyPage + 1 ; Wu2#r\
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return totalPage; m Wsegq4
} 1x V~EX
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privatestaticboolean hasPrePage(int currentPage){ :2
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return currentPage == 1 ? false : true; [64K?l0&
} rM2?"
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privatestaticboolean hasNextPage(int currentPage, vpMNulXb,
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int totalPage){ yaa+j8s]
return currentPage == totalPage || totalPage == =9LC"eI&|
\V7Hi\)
0 ? false : true; 3`5?Zgp
} 3BKW
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} U-Fr[1I6p
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3r%I *
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 b,#cc>76\
ahhVl=9/ao
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ygd'Nh!@
#D
.H2'_}
做法如下: <T+Pw7X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 $lU~3I)
u)t1t69T\g
的信息,和一个结果集List: #ie{!Mh
java代码: R
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^r(2
r
LZX-am`%
/*Created on 2005-6-13*/ V}'|a<8kVv
package com.adt.bo; ?:lOn(0&
Y GO ;wIS
import java.util.List; YzhZ%:8
0Dc$nL?TqX
import org.flyware.util.page.Page; )qzJu*cQ
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/** 8Nd +
* @author Joa 7>9/bB+TL
*/ $*G]6s
publicclass Result { <$Q&n{
R D=!No?
private Page page; :c!7rh7O
kD >|e<}\
private List content; fdck/|`t
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/** YxGIv8O]
* The default constructor !MTm4Ls
*/ oQjh?vm
public Result(){ v )%EG
super(); RVXRF_I
} C3G?dZKv2
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/** ZT"?W $
* The constructor using fields dU:s^^f&R
* TJ?}5h5
* @param page 2^[fUzL?
* @param content dn:g_!]p
*/ @ns2$(wkm@
public Result(Page page, List content){ /fBZRdB
this.page = page; wI#rAx7f-
this.content = content; (x>5
} 9/~m837x
^Ac0#oX]M
/** pZlBpGQf
* @return Returns the content. %vxd($Ti"
*/ 1Q#hanh_`
publicList getContent(){ _&19OD%
return content; m&Ms[X
} sOzjViv
)n5]+VTZ5
/** PcM:0(,G
* @return Returns the page. >^+Q`"SN
*/ >| .jG_s
public Page getPage(){ h'MX{Wm.
return page; }1:jM_H)k
} feQ_dA q
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/** rYJt;/RtR}
* @param content jcXb@FE6
* The content to set. L7X._XBO[
*/ TcauCL
public void setContent(List content){ UF D_
this.content = content; A!Xn^U*p
} y;;^o6Gnw
w{I60|C]*
/** Q]{DhDz?+
* @param page 7yeZ+lD
* The page to set. PM[6U#
*/ e7]IEBbX2O
publicvoid setPage(Page page){ S8.nM}x
this.page = page; qW?^_
} nFw&vR/q
} $`{}4,5M
G
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rH8?GR0<
_q3SR[k+`
2. 编写业务逻辑接口,并实现它(UserManager, ir \ d8.
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UserManagerImpl) I".d>]16|
java代码: 0t/ S_Q
kki]6_/n
CU lANd"
/*Created on 2005-7-15*/ T/-PSfbkj
package com.adt.service; .zBSjh_=H
n." j0kc7=
import net.sf.hibernate.HibernateException; S9U9;>g
}gag?yQ.^
import org.flyware.util.page.Page;
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import com.adt.bo.Result; XfViLBY(
>
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/** ZSKk*<=
* @author Joa &|/C*2A
*/ "O9uz$
publicinterface UserManager { gl2~6"dc
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public Result listUser(Page page)throws zT!JHG
H{p+gj^J
HibernateException; 8QFY:.h&
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} >]ZojdOl)
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0Zk A.p
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< g6
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java代码: KXicy_@DC`
B<8Z?:3YS
[#lPT'l
/*Created on 2005-7-15*/ Qnr' KbK
package com.adt.service.impl; 8$?a?7,>|
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import java.util.List; ${6 ;]ye
{ F.Ihw
import net.sf.hibernate.HibernateException; .'__ [|-{;
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import org.flyware.util.page.Page; >jN)9}3>-#
import org.flyware.util.page.PageUtil; Vwm\a]s
dXrv
import com.adt.bo.Result; M;\K+,
import com.adt.dao.UserDAO; qI8{JcFx:
import com.adt.exception.ObjectNotFoundException; xCoQ>.4p
import com.adt.service.UserManager; 9FcCq*D
9.vHnMcq
/** BO/2kL8*
* @author Joa R4@C>\c%m
*/ R^%7|
publicclass UserManagerImpl implements UserManager { NBUM* Z
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private UserDAO userDAO; z~z.J]
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/** ;9B:E"K?@1
* @param userDAO The userDAO to set. }6^(
*/ B0Xn9Tvk
publicvoid setUserDAO(UserDAO userDAO){ Q'$aFl'NR
this.userDAO = userDAO; zzq/%jki
} ?w3f;v
z'fGHiX7.0
/* (non-Javadoc) XK(<N<Z@|e
* @see com.adt.service.UserManager#listUser b4oZ@gVR;
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(org.flyware.util.page.Page) X1tAV>k5'L
*/ U{i9h6b"18
public Result listUser(Page page)throws {U-VInu
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HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); |`:Uww+3
if(totalRecords == 0) \$riwL
throw new ObjectNotFoundException O3Ks|%1
a&PoUwG
("userNotExist"); (Ozb +W?
page = PageUtil.createPage(page, totalRecords); L7a+ #mGE
List users = userDAO.getUserByPage(page); H'Z[3e
returnnew Result(page, users); jr~76
} !C#q
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} 8M(N
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gt}/C4|
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1)%9h>F7
s{<rc>
询,接下来编写UserDAO的代码: MEq
()}7P
3. UserDAO 和 UserDAOImpl: 0D$+WX
java代码: 6j_
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LT2mwJl
64b9.5Bn
/*Created on 2005-7-15*/ J^0co1Y0
package com.adt.dao; d-xKm2sH
vV"TTzs!
import java.util.List; r&Za*TD^
}IEYH&4!
import org.flyware.util.page.Page; [4t_ 83
f[h=>O
import net.sf.hibernate.HibernateException; =We}&80x
3#0nus|=S
/** Gh42qar`
* @author Joa s)xfTr_$
*/ cZ^$!0
publicinterface UserDAO extends BaseDAO { +w GE
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publicList getUserByName(String name)throws ]O&TU X@)
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HibernateException; So0YvhZ+
r{6 ,;
publicint getUserCount()throws HibernateException; T5W r;a
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publicList getUserByPage(Page page)throws K6!`b(
v#
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HibernateException; -D{~7&
1`B5pcuI
} z\fD}`^8
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m!E36ce}
java代码: #r:J,D6*
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v8-F;>H
/*Created on 2005-7-15*/ %o+bO}/9
package com.adt.dao.impl; _Ndy;MQ
w#XE!8`
import java.util.List; $0iz;!w
NjsP"
import org.flyware.util.page.Page; |K/#2y~
P|_?{1eO2
import net.sf.hibernate.HibernateException; ;?h#',(p
import net.sf.hibernate.Query; U{eC^yjt"o
bKG:_mWe w
import com.adt.dao.UserDAO; ~g>15b3
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/** hMhD(X
* @author Joa YM+}Mmu
*/ YN"102CK
public class UserDAOImpl extends BaseDAOHibernateImpl 2/?pI/W
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implements UserDAO { G}D?+MWY
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/* (non-Javadoc) Mr/^V,rA
* @see com.adt.dao.UserDAO#getUserByName >G/>:wwSP.
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(java.lang.String) mj5A*%"W
*/ D1#E&4
publicList getUserByName(String name)throws ((;9%F:/$
--",}%-
HibernateException {
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String querySentence = "FROM user in class v+G}n\F
a[ Txd=b
com.adt.po.User WHERE user.name=:name"; dA\>z[n=
Query query = getSession().createQuery :qgdn,Me
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(querySentence); pPG!{:YT
query.setParameter("name", name); fBw+Y4nCO7
return query.list(); _[XEL+.
} YVu8/D@ o
y%ER51+
/* (non-Javadoc) (IJf2
* @see com.adt.dao.UserDAO#getUserCount() f&^Ea-c
*/ Y k~ i.p
publicint getUserCount()throws HibernateException { _2f}WY3S
int count = 0; 8a.
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String querySentence = "SELECT count(*) FROM T7cT4PAW
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user in class com.adt.po.User"; S)JZb_
Query query = getSession().createQuery 4B (*{
>`,v?<>+
(querySentence); t#Yyo$9
count = ((Integer)query.iterate().next &sx/qS#,VL
{
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()).intValue(); CAcnH
return count; n (cSfT
} \2eYw.I=
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/* (non-Javadoc) 8 _`Lx_R
* @see com.adt.dao.UserDAO#getUserByPage ?:n{GK
tGM)"u-
(org.flyware.util.page.Page) Vy-S9=
*/ P]dDTh~e~
publicList getUserByPage(Page page)throws iP'}eQn]c
{fIH9+v
HibernateException { UPN2p&gM
String querySentence = "FROM user in class ;}|.crMF
aoF>{Z4&B
com.adt.po.User"; L)B?p!cdLT
Query query = getSession().createQuery o L6[i'H|
u$<FKp;I
(querySentence); @@ZcW<Y"
query.setFirstResult(page.getBeginIndex()) :MJBbrV
,
.setMaxResults(page.getEveryPage()); / HaS.
return query.list(); <JZ=K5
} L=HL1Qe$G]
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} A=h`Z^8\B
(7Y :3
TvI}yaCu/x
@&EE/j^
iCv &<C@
至此,一个完整的分页程序完成。前台的只需要调用 ^T^U:Zdq
{p6",d."N&
userManager.listUser(page)即可得到一个Page对象和结果集对象 |S>nfL{TQe
3t%uUkXl
的综合体,而传入的参数page对象则可以由前台传入,如果用 o2Pj|u*X
*jA%.F
webwork,甚至可以直接在配置文件中指定。 Hyee#fB
1egryp
下面给出一个webwork调用示例: I X\&