Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 NQdwj>_a
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 X|of87
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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 PQHztS"
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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 i).%GMv*r
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分页支持类: 46?z*~*G
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java代码: 529;_|
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package com.javaeye.common.util; >.?yz
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import java.util.List; /J`}o}
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publicclass PaginationSupport { 1$*8F
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publicfinalstaticint PAGESIZE = 30; /X}1%p
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privateint pageSize = PAGESIZE; x\yM|WGL
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privateList items; ;}B=g/C
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privateint totalCount; ZU\$x<,
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privateint[] indexes = newint[0]; Ws2q/[\oz
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privateint startIndex = 0; c &c
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public PaginationSupport(List items, int re/-Yu$'
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totalCount){ X@~/.H5
setPageSize(PAGESIZE); pSx5ume95"
setTotalCount(totalCount); lxn/97rA
setItems(items); 1hbQ30
setStartIndex(0);
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} 1j2U,_-
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public PaginationSupport(List items, int iM .yen_vp
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totalCount, int startIndex){ !}=eXDn;A_
setPageSize(PAGESIZE); ekx(i
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setTotalCount(totalCount); [if(B\&
setItems(items); `xM*cJTZ
setStartIndex(startIndex); G4
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} w,1N ;R&
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public PaginationSupport(List items, int ^gVQ6=z%
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totalCount, int pageSize, int startIndex){ wBt7S!>G
setPageSize(pageSize); !
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setTotalCount(totalCount); <Sot{_"li
setItems(items); )CXlPbhY?
setStartIndex(startIndex); 0Gu77&
} A
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publicList getItems(){ lBP?7`U
return items; TQ\#Z~CbK{
} %DuPM66r
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publicvoid setItems(List items){ dV$[O`F*b
this.items = items; V lZ+x)E
} B7Ket8<J
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publicint getPageSize(){ EWJB/iED
return pageSize;
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} J{/hc}
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publicvoid setPageSize(int pageSize){ PTHxvml
this.pageSize = pageSize; cc${[yj)
} \d:Q%S
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publicint getTotalCount(){ 6$"IeBRO
return totalCount; 1F.._5_"]
} s:{[Y7\?
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publicvoid setTotalCount(int totalCount){ W2`3 p
if(totalCount > 0){ 'e:4
this.totalCount = totalCount; ]MCH]/
int count = totalCount / U<Oc&S{]*
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pageSize; J_F\cM
if(totalCount % pageSize > 0) E+y_te^+b
count++; p;4FZ$
indexes = newint[count]; j*>]HNo&
for(int i = 0; i < count; i++){ "OwM'
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indexes = pageSize * :U\*4l
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} D*UxPm"pw
}else{ 2Ys=/mh
this.totalCount = 0; G;gsDn1t
} @zGF9O<3,@
} 2-m@-
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publicint[] getIndexes(){ l&\y]ZV={
return indexes; h]@'M1D%
} .XpuD,^;@
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publicvoid setIndexes(int[] indexes){ uou
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this.indexes = indexes; U]pE{^\w
} _"*vj-{-y
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publicint getStartIndex(){ ?uCL[
return startIndex; fFEB#l!oUb
} [cDkmRV
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publicvoid setStartIndex(int startIndex){ +M.BMS2A<l
if(totalCount <= 0) 86LE
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this.startIndex = 0; e R[B0;c
elseif(startIndex >= totalCount) lOA
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this.startIndex = indexes Y4YZM
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[indexes.length - 1]; x7B;\D#`i/
elseif(startIndex < 0) JCxQENsVqB
this.startIndex = 0; WBKf)A^S
else{ S9DXd]6q_
this.startIndex = indexes ;/NC[:'$D
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[startIndex / pageSize]; /nv*OKS|
} )Q9Qo)D T
} [1GwcXr
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publicint getNextIndex(){ C D6N8n]
int nextIndex = getStartIndex() + z,ryY'ua/I
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pageSize; F<h+d917
if(nextIndex >= totalCount) (k+*0.T&?
return getStartIndex(); 1q=Q/L4P
else _{): w~zi
return nextIndex; "+2Cs
} ,e|"p[z~T
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publicint getPreviousIndex(){ z\FBN=54z
int previousIndex = getStartIndex() - 4'3;{k$z
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pageSize; %4`
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if(previousIndex < 0) AP z"k?D0
return0; tvno3"
else v?8i;[
return previousIndex; PcbhylKd
} /\Cf*cJ
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} .dYv.[?hL
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抽象业务类 G8'{nPA~
java代码: t<c7%i#Od
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/** @}PXBU
* Created on 2005-7-12 M_+W5Gz<
*/ ^?]-Q*w3Qs
package com.javaeye.common.business; a/s5Oit2'X
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import java.io.Serializable; $XcH.z
import java.util.List; AJ}m2EH
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import org.hibernate.Criteria; iM7^
import org.hibernate.HibernateException; UM0Ws|qx&
import org.hibernate.Session; 0N)DHD?U
import org.hibernate.criterion.DetachedCriteria; T_s09Wl
import org.hibernate.criterion.Projections; L9^M?.a
import &2%|?f|
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org.springframework.orm.hibernate3.HibernateCallback; [QMN0#(h
import @x*xgf
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org.springframework.orm.hibernate3.support.HibernateDaoS Y6Y"fb%K
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upport; n>,GmCo
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import com.javaeye.common.util.PaginationSupport; _'G'>X>}WU
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public abstract class AbstractManager extends ]7TOA$Q
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HibernateDaoSupport { ;:oXe*d
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privateboolean cacheQueries = false; og8hc~:ro
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privateString queryCacheRegion; &2.DZ),L
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publicvoid setCacheQueries(boolean K2Ro0
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cacheQueries){
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this.cacheQueries = cacheQueries; y5*zyd
} &Qv HjjQ?u
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publicvoid setQueryCacheRegion(String aeNbZpFQ
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queryCacheRegion){ 8G$BQ
this.queryCacheRegion = B R
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queryCacheRegion; ZXo;E
} ~s-gnp
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publicvoid save(finalObject entity){ s8's(*]
getHibernateTemplate().save(entity); )2l @%?9
} yFeFI@Hp 3
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publicvoid persist(finalObject entity){ wC%qS y'
getHibernateTemplate().save(entity); y'b*Dk{
} R|$b\3
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publicvoid update(finalObject entity){ %rhZH^2
getHibernateTemplate().update(entity); p-\->_9)y`
} D/"velV
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publicvoid delete(finalObject entity){ J,?F+Qji&=
getHibernateTemplate().delete(entity); U8N X%*oW
} )HI\T];
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publicObject load(finalClass entity, 2<!IYEyT
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finalSerializable id){ {9{X\|
return getHibernateTemplate().load L#'XN H"
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(entity, id); g5pFr=NV
} :JX2GRL4
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publicObject get(finalClass entity, d^M*%a z
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finalSerializable id){ 479X5Cl
return getHibernateTemplate().get N2HD=[*cr
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(entity, id); PCL
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} 9,JM$ Y
{
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publicList findAll(finalClass entity){ G!B:>P|\l
return getHibernateTemplate().find("from m44a HBwId
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" + entity.getName()); ZCZ@ZN
} ^Lc\{,m
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publicList findByNamedQuery(finalString >W >Ei(f
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namedQuery){ +XO\#$o>W
return getHibernateTemplate })70S8k
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().findByNamedQuery(namedQuery); c'3N;sZ*B
} 45wtl/^9
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publicList findByNamedQuery(finalString query, ;ltk}hJ]
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finalObject parameter){ vOz1& |;D
return getHibernateTemplate Z|x|8 !D
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().findByNamedQuery(query, parameter); /RqWrpzx@
} }Md;=_TP
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publicList findByNamedQuery(finalString query, R)*DkL!
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finalObject[] parameters){ 9)W &yi
return getHibernateTemplate -3)jUzD
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().findByNamedQuery(query, parameters); j-R*!i
} pw4^E|X
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publicList find(finalString query){ M.s'~S7y
return getHibernateTemplate().find 1d FuoX
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(query); ,G}i:7
} [(3s5)O
*@PM,tS;
publicList find(finalString query, finalObject $F#
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parameter){ 8Vj'&UY
return getHibernateTemplate().find 7p2xst
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(query, parameter); 7_ayn#;y
} >O24#!9XW
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public PaginationSupport findPageByCriteria P$k*!j_W
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(final DetachedCriteria detachedCriteria){ }]mxKz
return findPageByCriteria mrnPZf i
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); e*lL.
} M:}u|
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public PaginationSupport findPageByCriteria f4Y)GO<R]
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(final DetachedCriteria detachedCriteria, finalint qT(6T P
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startIndex){ r
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return findPageByCriteria 1VM2CgR a
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(detachedCriteria, PaginationSupport.PAGESIZE, kq5X<'MM9N
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startIndex); W +ER'lX
} jmkOu5@
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public PaginationSupport findPageByCriteria KB](W
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(final DetachedCriteria detachedCriteria, finalint 7LVG0A2>7
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pageSize, 9K`_P] l2z
finalint startIndex){ ?BfE*I$\h
return(PaginationSupport) (VjU ,'h
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getHibernateTemplate().execute(new HibernateCallback(){ X@DW1<wEt
publicObject doInHibernate 2,q*[Kh1
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(Session session)throws HibernateException { 0(eaVi-%D
Criteria criteria = vsj4?0=
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detachedCriteria.getExecutableCriteria(session); b@;Wh-{d
int totalCount = [TFJb+N&
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((Integer) criteria.setProjection(Projections.rowCount Q&I`uS=F
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()).uniqueResult()).intValue(); .M^[/!
criteria.setProjection tWIJ,_8l
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(null); =zyA~}M2
List items = <R /\nY Xz
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criteria.setFirstResult(startIndex).setMaxResults /gZyl|kdy
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(pageSize).list(); '&![h7B
PaginationSupport ps = ~pQN#C)CO>
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new PaginationSupport(items, totalCount, pageSize, 'V]&X.=zC
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startIndex); ^E.L8
return ps; !o /=,ZIx
} 1Hr}n6s
}, true); 22CET9iCe
} +GI906K
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public List findAllByCriteria(final v.jxG{~.
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DetachedCriteria detachedCriteria){ K@O^\
return(List) getHibernateTemplate 'f-r 6'_ZX
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().execute(new HibernateCallback(){ ~Ba=nn8Cq
publicObject doInHibernate W}CM;~*L
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(Session session)throws HibernateException { x)~i`$
Criteria criteria = {p84fR1P
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detachedCriteria.getExecutableCriteria(session); 9RJF
return criteria.list(); h)HEexyRg
} g|>LT_
}, true); sCFxn
} H&)}Z6C"
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public int getCountByCriteria(final Cd}^&z
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DetachedCriteria detachedCriteria){ AI.(}W4]
Integer count = (Integer) n:%4SZn
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getHibernateTemplate().execute(new HibernateCallback(){ by/H:5}7
publicObject doInHibernate GXtK3YAr
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(Session session)throws HibernateException { vQljxRtW
Criteria criteria = x=oV!x
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detachedCriteria.getExecutableCriteria(session); gw]%:
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return N,Eap KG
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criteria.setProjection(Projections.rowCount +i&<`ov
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()).uniqueResult(); t*gZcw5 r
} .S/5kLul
}, true); !bE-&c
return count.intValue(); 6Wu*zY_+
} e73=*~kfR
} ^m |@pp
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用户在web层构造查询条件detachedCriteria,和可选的 51jgx,-|$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8s1nE_3
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PaginationSupport的实例ps。 hmu>s'
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ps.getItems()得到已分页好的结果集 [.gk{> #
ps.getIndexes()得到分页索引的数组 vd%g'fTy9
ps.getTotalCount()得到总结果数 4)S99|1
ps.getStartIndex()当前分页索引 zjpZ] $
ps.getNextIndex()下一页索引 : ky`)F`
ps.getPreviousIndex()上一页索引 0MW W(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4q}+8F`0F
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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 :@(('X(".
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一下代码重构了。 hd3
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我把原本我的做法也提供出来供大家讨论吧: V8^la'_j
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首先,为了实现分页查询,我封装了一个Page类: >JpBX+]5m
java代码: im<bo Mv
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/*Created on 2005-4-14*/ a:BW*Hy{\
package org.flyware.util.page; )1s5vNVa
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/** DrJ?bG;[
* @author Joa d:%b
* K./qu^+k
*/ ;TAj;Tf]H
publicclass Page { |N)Ik8
*~#I5s\s!
/** imply if the page has previous page */ 2u3Kyn
privateboolean hasPrePage; K10G+'H^
h `Lr5)B'
/** imply if the page has next page */ S!(3-{nC
privateboolean hasNextPage; n'~==2
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/** the number of every page */ 1m*)MZ)
privateint everyPage; EA"hie7
W$4$%r8
/** the total page number */ \V? .^/
privateint totalPage; mY"7/dw<v
8 A>OQR
/** the number of current page */ #l=yD]tPU
privateint currentPage; 1djZ5`+
6{h\CU}"
/** the begin index of the records by the current GG%b"d-
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query */ 2W,9HSu8
privateint beginIndex; vV,TT%J8D
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/** The default constructor */ IW~R{ ]6
public Page(){ i|eX X)$
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} +kL7"
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/** construct the page by everyPage 6jq*lnA%
* @param everyPage aU!}j'5Q
* */ ^ZwZze:2
public Page(int everyPage){ ^'`b\$km-0
this.everyPage = everyPage; )|~K&qn`
} x~e._k=
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/** The whole constructor */ *u},(4Qf
public Page(boolean hasPrePage, boolean hasNextPage, \Zj%eW!m
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int everyPage, int totalPage, hb`9Vn\-E
int currentPage, int beginIndex){ \|PiQy*_?
this.hasPrePage = hasPrePage; z?byNd8
this.hasNextPage = hasNextPage; irt9%w4"
this.everyPage = everyPage; & NYaKu,}
this.totalPage = totalPage; JW>k8QjyN
this.currentPage = currentPage; CIW4E
this.beginIndex = beginIndex; iLy^U*yK
} s= Fp[>qA
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/** `B%%2p&
* @return S;~eI8gQ"
* Returns the beginIndex. |Z:yd}d
*/ > Pw5!i\
publicint getBeginIndex(){ YVIE v
return beginIndex; \e86'&
} (0{Dn5MH
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/** K[T0);hZR
* @param beginIndex VVJ0?G
(?
* The beginIndex to set. "~4V(
*/ 5rsz2;#p
publicvoid setBeginIndex(int beginIndex){ ufXWK3~\
this.beginIndex = beginIndex; "Bd-h|J
} 9g6$"',H
[ V.67_~
/** L=lSW7R
* @return 9z(SOzZn
* Returns the currentPage. }B0[S_mw
*/ <"3q5ic/Z
publicint getCurrentPage(){ .j4y0dh33
return currentPage; 72nZ`u
} ChiIQWFE
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i'R
/** - Jaee,P
* @param currentPage "6U0
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* The currentPage to set. d"|_NG` vr
*/ PQaTS*0SXJ
publicvoid setCurrentPage(int currentPage){ dz^HN`AlzC
this.currentPage = currentPage; Gu$/rb?
} cH_qHXi[G
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/** |f_'(-v`E
* @return PzJ(Q
* Returns the everyPage. qiz(k:\o
*/ K|%Am4
publicint getEveryPage(){ ^G!cv
return everyPage; $0V+<
} Uu7]`U l
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/** t|U5]$5
* @param everyPage tA1?8`bQ
* The everyPage to set. bB<S4@jF8z
*/ 6,q0F*q
publicvoid setEveryPage(int everyPage){ \&F4Wl>`
this.everyPage = everyPage; [RBSUOF
} "(=g7,I4
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/** CR [>5/:M
* @return DuC#tDP
* Returns the hasNextPage. sc*R:"
*/ rWr'+v?
publicboolean getHasNextPage(){ `l45T~`]$
return hasNextPage; -r*|N.5c
} [8'?G5/n
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/** q^xG%YdPz+
* @param hasNextPage "M/c0`>C!i
* The hasNextPage to set. ';R]`vWFe
*/ QGN+f)
publicvoid setHasNextPage(boolean hasNextPage){ =-^A;AO(
this.hasNextPage = hasNextPage; x-i,v"8
} S(.J
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/** P5my]4|x
* @return #M!u';bZ
* Returns the hasPrePage. %oiF} >
*/ oG)T>L[&
publicboolean getHasPrePage(){ %U{6 `m
return hasPrePage; +2MF#{ tS
} Bw;isMx7
l~$)>?ZD
/** ;bwBd:Y
* @param hasPrePage nc1~5eo
* The hasPrePage to set. h;q&B9
*/ %ddH4Q/p
publicvoid setHasPrePage(boolean hasPrePage){ n[>hJ6
this.hasPrePage = hasPrePage; zU1D@
} > %KEMlKZ
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/** [pU(z'caS
* @return Returns the totalPage. -W!M:8
* 4}C
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*/ L9) gN.#
publicint getTotalPage(){ y],opG6
return totalPage; "6C
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} {N]WVp*R
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/** 8(`e\)%l0
* @param totalPage |kZ!-?9Z
* The totalPage to set. 8s22VL
*/ '=nmdqP
publicvoid setTotalPage(int totalPage){ <,$*(dX)(
this.totalPage = totalPage; C9+rrc@4
} (-yif&
"]jN'N(.
} G+#bO5
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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 E 14DZ
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个PageUtil,负责对Page对象进行构造: Mq~E'g4#
java代码: TeuZVy8a
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/*Created on 2005-4-14*/ AyQ5jkIE^{
package org.flyware.util.page; vRtERFL
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import org.apache.commons.logging.Log; M gP|'H3\
import org.apache.commons.logging.LogFactory; B^9C}QB
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/** hqeknTGsIn
* @author Joa +6>2= ,?Z
* r1F5'?NZ(0
*/ G\tN(%.f
publicclass PageUtil { Pz*BuL<
>!Gq[i0
privatestaticfinal Log logger = LogFactory.getLog [;hkT
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(PageUtil.class); V=fu[#<@Ig
b)a5LFt|
/** Q.9,W=<6
* Use the origin page to create a new page BHp>(7,
* @param page ] K&ca
* @param totalRecords H.M:
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* @return xY)eU;*
*/ !.%*Tp#k#
publicstatic Page createPage(Page page, int K"[jrvZ=
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totalRecords){ #IGcQY
return createPage(page.getEveryPage(), M
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page.getCurrentPage(), totalRecords); ThP~k9-
} 8Y%
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/** Qxy~%;X
* the basic page utils not including exception DEu0Z
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handler CD`6R.
* @param everyPage c\[&IlM
* @param currentPage l9/}fMi
* @param totalRecords cq]0|\Vz
* @return page OLF6["0Rn
*/ #k<l5x`
publicstatic Page createPage(int everyPage, int 6Jy%4]wK
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currentPage, int totalRecords){ e+#Oj
everyPage = getEveryPage(everyPage); jCj8XM{c>
currentPage = getCurrentPage(currentPage); _[8JSw7
int beginIndex = getBeginIndex(everyPage, >9XG+f66E
C%z9Q
currentPage); A##Q>|>)
int totalPage = getTotalPage(everyPage, Dd0yQgCu
b"@-9ke5I
totalRecords); nzxHd7NIZ
boolean hasNextPage = hasNextPage(currentPage, !p ~.Y+
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totalPage); kLs{B
boolean hasPrePage = hasPrePage(currentPage); %iPIgma
sMAH;'`!Eu
returnnew Page(hasPrePage, hasNextPage, &Odrq#o?R
everyPage, totalPage, _@?I)4n|
currentPage, ZH=Bm^
zI"&g]TV5
beginIndex); (j:[<U
} P\[K)N/ 1
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privatestaticint getEveryPage(int everyPage){ rx]Q,;"
return everyPage == 0 ? 10 : everyPage; ku57<kb
} W|;`R{<I%
oT:wGBW
privatestaticint getCurrentPage(int currentPage){ SANbg&$
return currentPage == 0 ? 1 : currentPage; MS2/<LD3d
} wBI:}N@.
IN;!s#cl:
privatestaticint getBeginIndex(int everyPage, int UC`sq-n
?3LV$S)U
currentPage){ uFuH/(}K[
return(currentPage - 1) * everyPage; |VE.khq#
} j^Qk\(^#IV
\4G9fR4
privatestaticint getTotalPage(int everyPage, int zB7^L^Y
u ?F},VL;
totalRecords){ "a _S7K
int totalPage = 0; Zq:
}SU
W }Ll)7(|T
if(totalRecords % everyPage == 0) [N*S5^>1
totalPage = totalRecords / everyPage; OvC@E]/+
else @VND}{j
totalPage = totalRecords / everyPage + 1 ; 1*#hIuoj'
mWoN\Rwj
return totalPage; )abH//Pps.
} &a >UVs?=
'&|%^9O/"
privatestaticboolean hasPrePage(int currentPage){ &B+_#V=X@
return currentPage == 1 ? false : true; *c.w:DkfB
} /gaC
/a$Zzs&xs
privatestaticboolean hasNextPage(int currentPage, 1)xj 'n
/ml+b8@
int totalPage){ K)Ya%%6[U#
return currentPage == totalPage || totalPage == HA$7Q~{N-t
RU.MJ
kYQ5
0 ? false : true; 2
=>3B
} 4;jAdWj3
+U1fa9NSn
e'v_eD T^
} /lHs]) ,
<g&GIFE,
Nb0T3\3W
RY,L'GtO
FD8
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 PJKxh%J
tOj5b7'ui
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 m,4'@jg0
uW(Ngcpr
做法如下: C3<_0eI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ][\ uH|
Nhjz~S<o
的信息,和一个结果集List: 'oBv(H
java代码: tnXW7ej ^
!*wd
d8
:K \IS `
/*Created on 2005-6-13*/ \u/=?b
package com.adt.bo; N>j*{]OY+{
I$TD[W
import java.util.List; s,laJf
Q."rE"}<
import org.flyware.util.page.Page; FGo)]U
>^f]Lgp
/** /PBK:B
* @author Joa a5]]AkvA
*/ !$-QWKD4
publicclass Result {
poZ&S
pL.~z
private Page page; 5tVg++I
"LZv\c~v,%
private List content; 3\B~`=*q/
LKud'
/** JS >"j d#
* The default constructor ~W gO{@Mw
*/ r_V^sX
public Result(){ Ys5Iqj=mp
super(); 1x0)mt3
} ;UQ&yj%x
'
b,zE[Q
/** T !pHT'J
* The constructor using fields M%eTNsbNm
* lzz68cT
* @param page =*WfS^O
* @param content fb!>@@9Z
*/ 8L))@SA+uJ
public Result(Page page, List content){ w (,x{Bg\
this.page = page; NCx)zJ\S
this.content = content; ^X*l&R_=R
} p!(]`N
cPl$N5/5
/** cc3+Wx_
* @return Returns the content. wD<W'K
*/ f./j%R@
publicList getContent(){ m?)F@4]
return content; ns[h_g!j;
} _lOyT$DN
T,4REbm^
/** P9# }aw+
* @return Returns the page. <
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*/ J\ ?
public Page getPage(){ ][T>052v
return page; q[.,i{2R}
} CakB`q(8
<*4r6UFR
/** gn${@y?
* @param content 'p,54<e
* The content to set. `9VRT`e
*/ wIQt
f|ZI>
public void setContent(List content){ )9rJ]D^B
this.content = content; DM !B@
} Y#Pg*C8>8
W'C~{}c=
/** ^<e(3S:
* @param page ~,84E [VV
* The page to set. 2MKB(;k
*/ 9C1\?)"D^e
publicvoid setPage(Page page){ l9$"zEC
this.page = page; !2g*=oY
} Y{dj~}mM+
} )!D,;,aQ
~w$ ^`e!]
U#n1N7P|$F
@yn1#E,
]A:G>K
2. 编写业务逻辑接口,并实现它(UserManager, 5SHZRF(. 2
5q.)K
f+
UserManagerImpl) E"Y[k8-:2/
java代码: Ivc/g,
zO)3MC7l*
)L7h:%h#
/*Created on 2005-7-15*/ h!]=)7x;
package com.adt.service; jL#`CD
Bjsg!^X7
import net.sf.hibernate.HibernateException; \w@ "`!%
,S=ur%
import org.flyware.util.page.Page; Md1ePp]
a"X9cU[
import com.adt.bo.Result; #;>v,Jo
]KRw[}z
/** 2xpI|+a%
* @author Joa YZ^;xV
*/ HY7#z2L
publicinterface UserManager { b(:U]>J
WQYw@M~4Q!
public Result listUser(Page page)throws e[L%M:e9U
#uH%J<U
HibernateException; (wZ/I(4
S8)6@ECC
} T
[2l32
yK:b$S
b*"%E,?
:pgpE0
&qae+p?
java代码: [#C(^J*@c
.L}k-8
5'[b:YC
/*Created on 2005-7-15*/ #qdfr3
package com.adt.service.impl; /gq
VXDY+`
c\(CbC
import java.util.List; &X
OFc.u
j.7BoV
import net.sf.hibernate.HibernateException; VPXUy=W
X< p KAO\
import org.flyware.util.page.Page; Y`!Zk$8
import org.flyware.util.page.PageUtil; Xg1QF^
aO$I|!tl
import com.adt.bo.Result; '@,M
'H{
import com.adt.dao.UserDAO; 4:Id8rzz
import com.adt.exception.ObjectNotFoundException; E4N{;'
import com.adt.service.UserManager; h_K!ch}
JWvL
/** c^EU&q{4
* @author Joa F>s5<pKAX
*/ Fhk`qh'i
publicclass UserManagerImpl implements UserManager { #hF(`oX}4K
oD&axNk
private UserDAO userDAO; <]h?_)
&O.lIj#FR
/** k^*S3#"
* @param userDAO The userDAO to set. 3/0E9'
*/ (od9adSehV
publicvoid setUserDAO(UserDAO userDAO){ 4S3uzy%
this.userDAO = userDAO; )V?:qCuY>
} N)^`
15w
K+@R [
/* (non-Javadoc) Q6rvTV'vv
* @see com.adt.service.UserManager#listUser R*r;`x
)lrmP(C*.a
(org.flyware.util.page.Page) wOs t).
*/ |WDMyKf6J
public Result listUser(Page page)throws D
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x /E<@?*:
HibernateException, ObjectNotFoundException { Av_JcH
int totalRecords = userDAO.getUserCount(); 9B?-&t
if(totalRecords == 0) 4Bz:n
throw new ObjectNotFoundException _%:$sAj
M#;"7Qg
("userNotExist"); `D={l29H
page = PageUtil.createPage(page, totalRecords); b,uudtlH
List users = userDAO.getUserByPage(page); EN;s
8sC!
returnnew Result(page, users); G#nZ%qQ:I
} ~X!Z+Vg
Wg!JQRHtT
} {Etvu
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cZlDdr%
EE$\8Gx']!
)uu1AbT+e
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 9vI<\
Xa
T1=T
询,接下来编写UserDAO的代码: ZfP$6%;_
3. UserDAO 和 UserDAOImpl: SZ(]su:
java代码: (]N- HN]v
qPF`=#
U;#9^<^
/*Created on 2005-7-15*/ T1#r>3c\
package com.adt.dao; :kQydCuK
Bvsxn5z+:
import java.util.List; < wi9
m6Mko2
import org.flyware.util.page.Page; t4v@d
@jY=b<
import net.sf.hibernate.HibernateException; h'ik19
v8f1o$R
/** 2xK v;
* @author Joa V;29ieE!
*/ 3>QkO.b
publicinterface UserDAO extends BaseDAO { w?:tce
@A'@%Zv-
publicList getUserByName(String name)throws 'M!M$<j
O_\%8*;
HibernateException; !QSj*)V#
^xm%~
publicint getUserCount()throws HibernateException; Mqv[7.|
cp$GP*{@
publicList getUserByPage(Page page)throws "Tz'j}< 9C
Fj4>)!^kM
HibernateException; *WaqNMD[%
WT63ve
} a(uZ}yS$
V@rqC[on
->L> `<7(
LR#BP}\b'
]p!)8[<
java代码: QTC!vKM
HT
."J
Q@KCODi
/*Created on 2005-7-15*/ 55Y a(E
package com.adt.dao.impl; 7z q@T]
Kv9Z.DY
import java.util.List; fPPC`d&Q3
ir|c<~_=
import org.flyware.util.page.Page; Kk`LuS?
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import net.sf.hibernate.HibernateException; ZeLed[J^xJ
import net.sf.hibernate.Query; 4-m6e$p;
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import com.adt.dao.UserDAO; zf;sdQ;4
'^)}"sZ@G
/** U0U y
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* @author Joa 8W Etm}
*/ 10_#Z~aU
public class UserDAOImpl extends BaseDAOHibernateImpl 7-gT:
s }Ql9
implements UserDAO { =;Dj[<mJ45
ly:2XvV3~
/* (non-Javadoc)
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* @see com.adt.dao.UserDAO#getUserByName e|N~tUVrrN
R$X~d8o>%
(java.lang.String) O,JS*jXl
*/ GZ^Qt*5 {
publicList getUserByName(String name)throws T@A Qe[U'v
*:"@
HibernateException { cj9C6Y!
String querySentence = "FROM user in class m!5Edo-;<
Zm0' p!
com.adt.po.User WHERE user.name=:name"; 5] LfJh+"n
Query query = getSession().createQuery z]7 /Gc,j
E>+>!On)b
(querySentence); yzT4D>1,
query.setParameter("name", name); |az2vD6P
return query.list(); "}V_.I*+
} IC?(F]$%>
u*/+cT
/* (non-Javadoc) uP+VS>b
* @see com.adt.dao.UserDAO#getUserCount() +Qf}&D_
*/ H@1}_d
publicint getUserCount()throws HibernateException { |nE4tN#J<
int count = 0; /3&MUB*z&y
String querySentence = "SELECT count(*) FROM 0` .5gxm
L0oVXmlr
user in class com.adt.po.User"; [Q+k2J_h
Query query = getSession().createQuery L7hRFf-o
G[1\5dK*uR
(querySentence); (zh[1[a
count = ((Integer)query.iterate().next tva=DS
NBHpM}1xtU
()).intValue(); yzv"sd[8N
return count; f,4erTBH
} . P+Qu
MqJ5|C.q
/* (non-Javadoc) +IO>%
* @see com.adt.dao.UserDAO#getUserByPage H8B$#.
z:4_f:70
(org.flyware.util.page.Page) {
:1XN
*/ 'ZB^=T
publicList getUserByPage(Page page)throws n}I?.r@e
&gPP#D6A
HibernateException { &O^-,n
String querySentence = "FROM user in class [q Uv|l1
vxHFNGI
com.adt.po.User"; r!
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Query query = getSession().createQuery X
=%8*_
7f4O~4.[i
(querySentence); x x4GP2
query.setFirstResult(page.getBeginIndex()) N#2ldY *
.setMaxResults(page.getEveryPage()); =YTcWB
return query.list(); ^sB0$|DU
} 3H`{
A/r
vENf3;o0
} mf)+ 5On
ZXGi> E
QW$p{ zo
l<BV{Gl
!1fZ7a
至此,一个完整的分页程序完成。前台的只需要调用 U8AH,?]#
QeG9CS)E}j
userManager.listUser(page)即可得到一个Page对象和结果集对象 |?ssHW
HC/z3b;
的综合体,而传入的参数page对象则可以由前台传入,如果用 e"52'zAV-
~7 U~
webwork,甚至可以直接在配置文件中指定。 w7o`BR
naW!b&:
下面给出一个webwork调用示例: >W;NMcN~
java代码: Id##367R
P/dnH
"X8jpg
/*Created on 2005-6-17*/ c~?Zmdn:
package com.adt.action.user; r`.N?
[IQ|c?DxpL
import java.util.List; q+y\pdhdO
&'x~<rx
import org.apache.commons.logging.Log; 0=#>w_B
import org.apache.commons.logging.LogFactory; mr^3Y8$s
import org.flyware.util.page.Page; 2Jio_Hk
]Ob|!L(
import com.adt.bo.Result; 18!y7
_cFT
import com.adt.service.UserService; ##*]2Dy
import com.opensymphony.xwork.Action; G %6P`:
[104;g <
/** a9z#l}IQ
* @author Joa m^G(qoZ]
*/ P0jr>j@^-
publicclass ListUser implementsAction{ b.@a,:"
{VE
h@yn
privatestaticfinal Log logger = LogFactory.getLog 'Vo8|?.WhX
S k~"-HL|
(ListUser.class); CMaph
-g]Rs!w'
private UserService userService; L"NHr~
m&Mupl
private Page page; Ch_rV+
8s@N NjV
privateList users; %)x9u$4W2
sfj+-se(K.
/* DzQBWY]
)
* (non-Javadoc) /N"3kK,N
* =d<RgwscJ
* @see com.opensymphony.xwork.Action#execute() q.VYPkEib
*/ (Z
SaAn),
publicString execute()throwsException{ pW(rNAJ!
Result result = userService.listUser(page); {K]5[bMT
page = result.getPage(); {O^u^a\m
users = result.getContent(); !qj[$x-ns
return SUCCESS; <4"-tYa
} La;G S
Aw |;C
/** FM >ae-L-
* @return Returns the page. [d6!
*/ |)29"_Kk5
public Page getPage(){ jC9us>b
return page; yZ|"qP1
} ^Tm`motzh
s|]g@czan
/** K>@yk9)vi
* @return Returns the users. 8AuBs;i
*/ ]
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publicList getUsers(){ c+9L6}D
return users; 6<._^hyq
} "6$V1B0KW
MC}t8L=
/** @1JwjtNk
* @param page hj [77EEz
* The page to set. d,V#5l-6
*/ ,Of^xER`
publicvoid setPage(Page page){ O1J&Lwpk,
this.page = page; q8v[u_(yD
} -3EQRqVg
b-&iJ &>'
/** ;uUFgDi
* @param users :8A+2ra&
* The users to set. Ey&H?OFiP
*/ {r,Uik-nL
publicvoid setUsers(List users){ wA=r]BT
this.users = users; G<;~nAo?f0
} $J`O-"M
h:YD$XE
/** \k.`xG?
* @param userService N+|NI?R?}
* The userService to set. GM%+yS}(P
*/ }02`ve*
publicvoid setUserService(UserService userService){ 1F^Q* t{
this.userService = userService; 9-KhJq%
} }}AIpYp,P
} ^Xk!wJ
I&;>(@K
P[nc8z[
~[g(@Xt
21uK&nVf^l
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Jz}nV1G(jz
#DTKz]i?
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 rs&]46i/p
q$Gs;gz^(
么只需要: B0fOAP1
java代码: MtLWpi u@[
XO <wK
Z*%;;&?
<?xml version="1.0"?> m1"m KM
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 8i#
Rh!UbEPjC
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 06&J!,p
:
:C~Ar]
1.0.dtd"> Kg[OUBv
'wND
<xwork> .DCHc,DxA
RgJ@J/p"
<package name="user" extends="webwork- Ys"wG B>
/{i~CGc;"
interceptors"> ?[D3-4
F "@% 7xy
<!-- The default interceptor stack name x84!/n^z
-aoYoJ '
--> 4T@:_G2b
<default-interceptor-ref [{znwK@
iNO>'7s7
name="myDefaultWebStack"/> 37#&:[w>
_C?j\Wy
<action name="listUser" LW %AZkAx
:QE5 7.
class="com.adt.action.user.ListUser"> {%V(Dd[B6
<param |VBt:dd<
Yh":>~k?SY
name="page.everyPage">10</param> {ZJO5*
<result 9BCW2@Kp
=kjKK
name="success">/user/user_list.jsp</result> j]Auun
</action> dGIdSQ~ _
Rn1oD3w
</package> .Ro/ioq
LD$5KaOW
</xwork> Z*,e<zNQ
Av X1*
N'Gq9A
XHr*Rs.[=
w+M/VsL
{!"UBALxc
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 *$tXm4
O[
3<0b_b
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 )DSeXS[
e
(`x_MTLL
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 6#=jF[
*Rgr4-eS
-9Q(3$}
Lkt4F
LU1I
`E
我写的一个用于分页的类,用了泛型了,hoho h<9s&
p
jUe@xis<T
java代码: o2/:e
s\*L5{kiSl
4>JSZ6i#n
package com.intokr.util; KkvcZs'4m
L4By5)
import java.util.List; o3J#hQrl
H;Wrcf2
/** O[@!1SKT0
* 用于分页的类<br> xQoZ[
* 可以用于传递查询的结果也可以用于传送查询的参数<br> u?osX;'w
* L\:|95Yq
* @version 0.01 VUb>{&F[
* @author cheng q6zVu(
*/ 7CIN!vrC|1
public class Paginator<E> { /x VHd
privateint count = 0; // 总记录数 @CprC]X
privateint p = 1; // 页编号 aukcO;oG<
privateint num = 20; // 每页的记录数 tpfgUZ{
privateList<E> results = null; // 结果 Z}W{ iD{
87 Z[0>
/** LGP"S5V
* 结果总数 ;kFD769DLw
*/ ClG%zE&i
publicint getCount(){ 2qMiX|Y
return count; wQ_4_W
} ~#_~DqbMZ5
:@A&HkF
publicvoid setCount(int count){ Y
},E3<
this.count = count; /K=OsMl2b8
} u4x-GObJM
L2}\Ah"[
/** /6x&%G:m#
* 本结果所在的页码,从1开始 8 Rx@_
* l|CM/(99-
* @return Returns the pageNo. _N DQ2O
*/ uP~,]ci7
publicint getP(){ ^T=9j.e'ja
return p; B8&q$QV
} q_M N
\PrJy6&
/** iw@rW5%'~
* if(p<=0) p=1 L9b.D<
* u3T-U_:jSV
* @param p mm/\\my
*/ rrD6x>
publicvoid setP(int p){ TdhfX {nk
if(p <= 0) TxrW69FV7
p = 1; I
_nQTWcm
this.p = p; "1O_h6C
} n,N->t$i
#bOv}1,s
/** M/3;-g
* 每页记录数量 m+QS -woHn
*/ #s)f3HU>
publicint getNum(){ o9kJ90{D=
return num; ,K5K?C$k
} H.5
6
m=l>8
/** uGU2
* if(num<1) num=1 0.MB;gm:
*/ <)qa{,GX\
publicvoid setNum(int num){ <=(K'eqC^
if(num < 1) 7 N}@zPAZ
num = 1; 7Cz~nin>7
this.num = num; 26V6Y2X
} T(!1\ TB
*zrT;jG
/** m&)/>'W
* 获得总页数 rH}|~
*/ LjKxznn o
publicint getPageNum(){ U[]yN.J
return(count - 1) / num + 1; x]^d'o:cDP
} /s?%ft#-9o
7@ym:6Y+]
/** \!ZA#7
* 获得本页的开始编号,为 (p-1)*num+1 /b+~BvTh
*/ "4b{YWv
publicint getStart(){ o&JoeKXor
return(p - 1) * num + 1; ,!=
sGUQ)
} 5Tsz|k
"x$@^
/** ,&[o:jTk
* @return Returns the results. I4Do$&9<D
*/ CD1Ma8I8
publicList<E> getResults(){ R|?n
return results; B`SX3,3
} <spG]Xa<
x[A|@\Z
public void setResults(List<E> results){ V&zeC/xSq
this.results = results; oodA&0{)d
} 6
AO(A
*
2;)IBvK
public String toString(){ /xn|d#4
StringBuilder buff = new StringBuilder 2> a&m>
,xwiJfG;
]
(); #X(2
buff.append("{"); 1P)K@j
buff.append("count:").append(count); pH~\~
buff.append(",p:").append(p); 4LSs WO<@
buff.append(",nump:").append(num); | W@ ~mrO
buff.append(",results:").append I:dUHN+@L5
tI^91I
(results); f6r!3y
buff.append("}"); a1,)1y~
return buff.toString(); w1Bkz\95
} rCJ$Pl9R
.ATpwFal
} 3.movkj
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C eEhe