Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N,NEg4 q[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %
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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 (|<.7K N
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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 Tn8GLn
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分页支持类: ' fm}&0
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java代码: F45UO%/P
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package com.javaeye.common.util; +'!vm6
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import java.util.List; UN*XLHio
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publicclass PaginationSupport { Mw+8p}E
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publicfinalstaticint PAGESIZE = 30; d4zqLD$A
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privateint pageSize = PAGESIZE; T&`H )o
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privateList items; Lcyj,R
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privateint totalCount; |YAnd=$
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privateint[] indexes = newint[0]; 77ID
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privateint startIndex = 0; GM<r{6Qy
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public PaginationSupport(List items, int _=eeZ4f
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totalCount){ UE9r1g`z
setPageSize(PAGESIZE); |F 18j9
setTotalCount(totalCount); 3;J)&(j0
setItems(items); {~ngI<
setStartIndex(0); A;A>Q`JJF
} to
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public PaginationSupport(List items, int }~RH!Q1
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totalCount, int startIndex){ :!f1|h
setPageSize(PAGESIZE); OW12m{
setTotalCount(totalCount); A,T3%TE
setItems(items); Sgt@G=_o
setStartIndex(startIndex); .{1MM8 Q
} ?*Kewj
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public PaginationSupport(List items, int &\0`\#R
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totalCount, int pageSize, int startIndex){ P:")Qb2
setPageSize(pageSize); {AY`\G
setTotalCount(totalCount); e>kw>%3bl9
setItems(items); E30VKh |
setStartIndex(startIndex); J!:ss
} g[P8
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publicList getItems(){ &r;4$7
return items; Pxj?W'|
} 8L?35[]e
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publicvoid setItems(List items){ )up!W4h6o
this.items = items; Z=Oo%lM6B
} eFPDW;
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publicint getPageSize(){ `q
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return pageSize; <o_H]c->
} IdlW[h3`[
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publicvoid setPageSize(int pageSize){ v|XEC[F
this.pageSize = pageSize; #isBE}sT{
} g=;c*{
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publicint getTotalCount(){ S)[`Bm
return totalCount; H!ZPP8]j>
} or u.a
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publicvoid setTotalCount(int totalCount){ @^vVou_
if(totalCount > 0){ X}yEMe{T
this.totalCount = totalCount; XY5I5H_U
int count = totalCount / nJYcC"f
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pageSize; 7 3k3(rZ
if(totalCount % pageSize > 0) Nd&u*&S
count++; kg$<^:uX
indexes = newint[count]; ~h;c3#wuc
for(int i = 0; i < count; i++){ DiAPs_@
indexes = pageSize * %cD7}o:u
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} ~PUz/^^
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}else{ w $7*za2
this.totalCount = 0; 33\{S$p
} \HDRr*KO
}
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publicint[] getIndexes(){ <3QE3;4
return indexes; G1Cn[F;e
} }0T1* .Cz
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publicvoid setIndexes(int[] indexes){ =@m|g )
this.indexes = indexes; .h^."+TJ
} +EcN[-~
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publicint getStartIndex(){ ?0+D1w
return startIndex; 9[|Ql
} Pe/cwKCI
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publicvoid setStartIndex(int startIndex){ #5T+P8
if(totalCount <= 0) +"a .,-f!
this.startIndex = 0; <!&&Qd-d6H
elseif(startIndex >= totalCount) DL2gui3
this.startIndex = indexes
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[indexes.length - 1]; S@zsPzw
elseif(startIndex < 0) "7RQrz
this.startIndex = 0; '?_;s9)
else{ e.i5j^5u
this.startIndex = indexes UR?[ba_h
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[startIndex / pageSize]; 8@qYzSx[
}
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} dKw*L|5
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publicint getNextIndex(){ 4)iSz>
int nextIndex = getStartIndex() + S
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{
pageSize; =_8
if(nextIndex >= totalCount) KLs%{'[7:
return getStartIndex(); VZJs@qx:Z
else }}Eko7'^
return nextIndex; J(S.iTD
} CJ&0<Z}{m
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publicint getPreviousIndex(){ gmWRw{nS+
int previousIndex = getStartIndex() - W z3y+I/&
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pageSize; vI#\Qe
if(previousIndex < 0) #OH-LWZh
return0; D2~e@J(K
else H__9%p#
return previousIndex; K3TMT Y<p
} M=e]v9
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} C2,,+* v
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抽象业务类 vj^vzFb K
java代码: ;&P%A<[`
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/** R\MM2_I
* Created on 2005-7-12 _;{n+i[
*/ (D{Fln\
package com.javaeye.common.business; k#E D#']N
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import java.io.Serializable; 8\`]T%h
import java.util.List; 4)-LlYS_d<
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import org.hibernate.Criteria; >"B95$x5
import org.hibernate.HibernateException; (J][(=s;a
import org.hibernate.Session; wnP#.[,V
import org.hibernate.criterion.DetachedCriteria; zhU)bb[A
import org.hibernate.criterion.Projections; c{6!}0Q4
import bJ]g2C7`36
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org.springframework.orm.hibernate3.HibernateCallback; )wo'i]#2:
import =g2;sM/
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org.springframework.orm.hibernate3.support.HibernateDaoS "Nn/vid;
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upport; .#6Dad=S*
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import com.javaeye.common.util.PaginationSupport; fEWS3`Yy
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public abstract class AbstractManager extends sbrU;X_S
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HibernateDaoSupport { y1(smZU
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privateboolean cacheQueries = false; )Rn}4)9!iT
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privateString queryCacheRegion; Ja|! fT
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publicvoid setCacheQueries(boolean *]p]mzc
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cacheQueries){ T#Qn\8
this.cacheQueries = cacheQueries; #]oVVf_
} YL=?N k/
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publicvoid setQueryCacheRegion(String A}FEM[2
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queryCacheRegion){ B5IS-d
this.queryCacheRegion = B8'" ^a^&-
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queryCacheRegion; cV_nYcLkz
} C#`eN{%.YT
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publicvoid save(finalObject entity){ ync2X{9D
getHibernateTemplate().save(entity); zJOjc/\
} G7DEavtr
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publicvoid persist(finalObject entity){ n@mWBUM
getHibernateTemplate().save(entity); }>=k!l{
} 3205gI,
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publicvoid update(finalObject entity){ p}hOkx4R\
getHibernateTemplate().update(entity); 7KnZ
} cj`g)cX|
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publicvoid delete(finalObject entity){ ec[S?-
getHibernateTemplate().delete(entity); aIpDf|~
} KcglpKV`
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publicObject load(finalClass entity, Xa.Qt.C
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finalSerializable id){ 8xs[{?|:
return getHibernateTemplate().load E9;cd$}K
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(entity, id); R)"Ds}1G
} v9(->X'
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publicObject get(finalClass entity, Pdmfn8I]%
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finalSerializable id){ (n05MwKu\
return getHibernateTemplate().get D+]#qS1q
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(entity, id); YQvN;W
} y~w2^VN=
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publicList findAll(finalClass entity){ bX:Y5o49
return getHibernateTemplate().find("from lOt3^`
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" + entity.getName()); o"->RC
} !s06uh
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publicList findByNamedQuery(finalString >t&Frw/Bl
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namedQuery){ QU_O9 BN
return getHibernateTemplate oJ\UF S
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().findByNamedQuery(namedQuery); .$y}}/{j?[
} ]y>)es1
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publicList findByNamedQuery(finalString query, + pZ, RW.D
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finalObject parameter){ s9>f5u?dK
return getHibernateTemplate Q0i.gEwe
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().findByNamedQuery(query, parameter); H'Bor\;[>
} r t@Jw]az
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publicList findByNamedQuery(finalString query, l&S2.sC
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finalObject[] parameters){ v*SSc5gFG
return getHibernateTemplate AA"?2dF
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().findByNamedQuery(query, parameters); LF vKF .
} >j5)
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publicList find(finalString query){ I
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return getHibernateTemplate().find 4n @}X-)
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(query); fNNkc[YTZI
} ^I=c]D]);
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publicList find(finalString query, finalObject D::$YR
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parameter){ XW
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return getHibernateTemplate().find '^)Ve:K-.
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(query, parameter); D7H,49#1Q
} @d]I3?`
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public PaginationSupport findPageByCriteria / PDe<p
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(final DetachedCriteria detachedCriteria){ kwU~kcM
return findPageByCriteria rxH*h`Xx@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); p%toD{$
} 8d|omqe~P
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public PaginationSupport findPageByCriteria jX}}^XwX
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(final DetachedCriteria detachedCriteria, finalint ++n"`
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startIndex){ 83~
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return findPageByCriteria DG,CL8bv
V #["Z}
(detachedCriteria, PaginationSupport.PAGESIZE, \]ouQR.t@\
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startIndex); Dnn$-W|NC
} gpW3zDJ
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public PaginationSupport findPageByCriteria Pw
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(final DetachedCriteria detachedCriteria, finalint ngJi;9X8*t
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pageSize, _Mq0QQ42
finalint startIndex){ 2c`m8EaJ
return(PaginationSupport) vH/z|<
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getHibernateTemplate().execute(new HibernateCallback(){ )';Rb$<Qn
publicObject doInHibernate [lZo'o
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(Session session)throws HibernateException { Q;{[U!\:
Criteria criteria = gZ%wmY
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detachedCriteria.getExecutableCriteria(session); iJ.P&T9
int totalCount = `X[L62D
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((Integer) criteria.setProjection(Projections.rowCount n!=%MgF'*p
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()).uniqueResult()).intValue(); ReE-I/n8f
criteria.setProjection zK`fX
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(null); XOgl>1O
List items = V^fSrW]
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criteria.setFirstResult(startIndex).setMaxResults ?z3c$}
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(pageSize).list(); a)J3=Z-
PaginationSupport ps = 9l).L L
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new PaginationSupport(items, totalCount, pageSize, 7L~LpB
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startIndex); > w:+nG/r
return ps; fDyFkhc
} bl@0+NiM
}, true); #U45H.Rz
} @V{s'V
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public List findAllByCriteria(final ]"bkB+I
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DetachedCriteria detachedCriteria){ `L p3snS
return(List) getHibernateTemplate XQL"D)fw
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().execute(new HibernateCallback(){ Sh'>5z2
publicObject doInHibernate rmpx8CY"
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(Session session)throws HibernateException { @y:mj \J9
Criteria criteria = %-ih$ZY
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detachedCriteria.getExecutableCriteria(session); cx%[hM09
return criteria.list(); |O0=Q,<m
} *?jU$&Qpj*
}, true); s/ [15
} _22;hnG<iy
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public int getCountByCriteria(final Y"qKe,
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DetachedCriteria detachedCriteria){ H |8vW
Integer count = (Integer) MgJiJ0y
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getHibernateTemplate().execute(new HibernateCallback(){ @Dc?fyY*o<
publicObject doInHibernate \2cbZQx
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(Session session)throws HibernateException { r,}U-S.w
Criteria criteria = xK4b(KJj
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detachedCriteria.getExecutableCriteria(session); T&Dt;CSF
return W\09hZ6
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criteria.setProjection(Projections.rowCount s+Qm/ h2
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()).uniqueResult(); 9L3#aE]C
} i8R.Wl$l
}, true); 8joJe>9VJ
return count.intValue(); zTi%j$o
} ;)Rvk&J5
} |k5uVhN
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用户在web层构造查询条件detachedCriteria,和可选的 cgKK(-$ny
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 cU}j
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PaginationSupport的实例ps。 [s?H3yQ.
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ps.getItems()得到已分页好的结果集 C6Qnn@waYb
ps.getIndexes()得到分页索引的数组 \ZdV|23
ps.getTotalCount()得到总结果数 LF+#PnK
ps.getStartIndex()当前分页索引 n99>oh
ps.getNextIndex()下一页索引 bni :B?#
ps.getPreviousIndex()上一页索引 u@d`$]/>F
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 "B`yk/GM]
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ) *:<3g!
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一下代码重构了。 *yAC8\v
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我把原本我的做法也提供出来供大家讨论吧: /'U/rjb_h{
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首先,为了实现分页查询,我封装了一个Page类: >@^z?nb
java代码: c_b^t09
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/*Created on 2005-4-14*/ 1G/bqIMg63
package org.flyware.util.page; Ve>*KHDSt
_%Q\G,a;
/** =L~,HS(l,
* @author Joa @]lKQZ^2&
* .E:QZH' M
*/ C:/ca)
publicclass Page { Zab5"JR
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/** imply if the page has previous page */ *LJN2;
privateboolean hasPrePage; BBw]>*
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/** imply if the page has next page */ k)\Yl`4au
privateboolean hasNextPage; ~ar8e
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/** the number of every page */ pK O\tkMJ
privateint everyPage; vGWX= O
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/** the total page number */ V.J[Uwf
privateint totalPage; d#7 z
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/** the number of current page */ ?}^e,.M0?s
privateint currentPage; Q1V 4bmM
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/** the begin index of the records by the current :,<e
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query */ -)@DH;[tb
privateint beginIndex; G`E%uyjG$j
*g&[?y`UC
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/** The default constructor */ ?b, eZ+t
public Page(){ %w7J0p
cT^,[3i:c
} eG26m_S=
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/** construct the page by everyPage J'tc5Ip!}V
* @param everyPage c>d+q9M
* */ `.nkC_d
public Page(int everyPage){ j eMh
this.everyPage = everyPage; #:L|-_=a
} '7[{ISBXU
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/** The whole constructor */ Fc>W]1
public Page(boolean hasPrePage, boolean hasNextPage, :av6*&+
c_a*{L|c
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int everyPage, int totalPage, `/ix[:}m^
int currentPage, int beginIndex){ P7d" E
this.hasPrePage = hasPrePage; J!%Yy\G
this.hasNextPage = hasNextPage; Q/4g)( ~J
this.everyPage = everyPage; q.i@Lvu#
this.totalPage = totalPage; Q)yhpwrX
this.currentPage = currentPage; mJ0nyjX^
this.beginIndex = beginIndex; ?1}1uJMj-
} OtJYr1:y_
pgT{#[=>
/** &!JX
* @return {6'5K
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* Returns the beginIndex. YcE:KRy
*/ X4*{CM
publicint getBeginIndex(){ mzTF2K
return beginIndex; [>&Nhn0iY
} '#[U7(lIQ
%b'ic
/** ohusL9D
* @param beginIndex 2H fP$.
* The beginIndex to set. wG2lCv`d
*/ ON _uu]=
publicvoid setBeginIndex(int beginIndex){ YTxUKE:
this.beginIndex = beginIndex; Rj9ME,u
} 0wXfu"E{
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/** a9Lf_/w{ &
* @return `7}6
* Returns the currentPage. ?rXh
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*/ My'M~#kO,
publicint getCurrentPage(){ & PrV+Lv
return currentPage; =K{$?%"
} K,%H*1YKK
#wbaRx@rc
/** p#'BV'0bl
* @param currentPage s0v?*GRX
* The currentPage to set. V^nYG$si
*/ ~;#J&V@D
publicvoid setCurrentPage(int currentPage){ &$jg *Kr
this.currentPage = currentPage; C ,z7f"
} EaFd1
}Y[Z`w
/** '(Uyju=
* @return c`mJrS:
* Returns the everyPage. b_cnVlN[
*/ Y'S xehx
publicint getEveryPage(){ ?mS798=f
return everyPage; 4JFi|oK0H
} &M=12>ah]
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/** o %A4wEye
* @param everyPage lYT}Nc4"="
* The everyPage to set. CjORL'3
*/ 75wQH*
publicvoid setEveryPage(int everyPage){ `rW{zQYM
this.everyPage = everyPage; :+ @-F>Q
} h1G]w/.ws
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/** i;*c|ma1>
* @return zC!]bWsD
* Returns the hasNextPage. l@4hBq
*/ |M`B
publicboolean getHasNextPage(){ j{>E.F2.
return hasNextPage; k!t5>kPSQ
} Fp+^`;j
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/** inZMq(_@$
* @param hasNextPage <|k!wfHL
* The hasNextPage to set. D}vgXzD
*/ KM< +9`
publicvoid setHasNextPage(boolean hasNextPage){ YTQ|Hg6jO
this.hasNextPage = hasNextPage; D; H</5#Q
} ?cCh?>h
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/** mJ<rzX
* @return RW48>4f/+
* Returns the hasPrePage. gWqmK/.U.0
*/ )Ac8'{Tq/
publicboolean getHasPrePage(){ j#Ly!%dp
return hasPrePage; VXZd RsV8T
} HnUM:-6
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/** +`u]LOAyP=
* @param hasPrePage >#*]/t
* The hasPrePage to set. X<K[`
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*/ ;5ugnVXu
publicvoid setHasPrePage(boolean hasPrePage){ RPPxiYU^
this.hasPrePage = hasPrePage; 2,/("lV@0
} IE: x&q`3
G%;XJsFGp
/** wJ1qJ!s@
* @return Returns the totalPage. lg&"=VXx51
* %;^[WT`,
*/ g$ZgR)q
publicint getTotalPage(){ MA.1t
return totalPage; 4otB1{
} a3 6n}R4Q
k^z)Vu|f.
/** d"Y9go"Z
* @param totalPage c~ l$_A
* The totalPage to set. fW!~*Q
*/ .
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publicvoid setTotalPage(int totalPage){ ss T o?WL|
this.totalPage = totalPage; EyI
9$@4
} P9:7_Vc
!w]!\H
} y1cAw
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ,[,+ _A
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个PageUtil,负责对Page对象进行构造: g~h`wv'
java代码: "'94E,W
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/*Created on 2005-4-14*/ ymY,*Rb
package org.flyware.util.page; JMuUj_^}7
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import org.apache.commons.logging.Log; Au#(guvm
import org.apache.commons.logging.LogFactory; 0?BT*
/8q7pwV
/** 3F5r3T6j}
* @author Joa
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* z[0L?~$
*/ 7XT2d=)"
publicclass PageUtil { 8UwL%"?YB
`O.*qs5
privatestaticfinal Log logger = LogFactory.getLog uh\I'
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(PageUtil.class); -kq=W_
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/** ,COSpq]6
* Use the origin page to create a new page (:,N?bg
* @param page OQ
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* @param totalRecords 1{_tV^3@
* @return fxI>FhU_
*/ ]]d9\fw
publicstatic Page createPage(Page page, int D}HW7Hnu^
KNC!T@O|{#
totalRecords){ ;x@9@6_
return createPage(page.getEveryPage(), 9x ?" %b
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page.getCurrentPage(), totalRecords); RSG4A>%!mI
} g (ZeGNV8
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/** t#&^ -;
* the basic page utils not including exception "%D+_Yb'X
c;Hf +n
handler mc?5,oz;pz
* @param everyPage F&lWO!4
* @param currentPage q!7z4Cn
* @param totalRecords 6?+bi\6
* @return page P}~6yX
*/ qdCa]n!d
publicstatic Page createPage(int everyPage, int .oO_x>
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currentPage, int totalRecords){ r,2x?Qi
everyPage = getEveryPage(everyPage); ]r$S{<
currentPage = getCurrentPage(currentPage); 09_3`K.*
int beginIndex = getBeginIndex(everyPage, 9TO
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currentPage); !Lb9KDk
int totalPage = getTotalPage(everyPage, Kk!D|NKLC
t.j q]L
totalRecords); R7KHfXy'm
boolean hasNextPage = hasNextPage(currentPage,
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.P# c/SQp
totalPage); l4O}>#
boolean hasPrePage = hasPrePage(currentPage); I= x
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returnnew Page(hasPrePage, hasNextPage, %~4R)bsJ'
everyPage, totalPage, 7xVI,\qV
currentPage, bo$xonV @y
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beginIndex); Xleoh2&M
} @_FL,AC&m
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privatestaticint getEveryPage(int everyPage){ 4^w>An6
return everyPage == 0 ? 10 : everyPage; RB\>$D
} bG^E]a/D
CmJI"
privatestaticint getCurrentPage(int currentPage){ mz+>rc
return currentPage == 0 ? 1 : currentPage; xaoaZ3Ko
} A>%fE 6FY
ti`z:8n7
privatestaticint getBeginIndex(int everyPage, int m589C+7
NrgN{6u;
currentPage){ }qmZ
return(currentPage - 1) * everyPage; qX0IHe
} I:]s/r7
XsQ<yeun
privatestaticint getTotalPage(int everyPage, int cI?dvfU?
=5oFutg`
totalRecords){ }dAb}0XK.
int totalPage = 0; 1#(,Bq4
2OAh7 '8<
if(totalRecords % everyPage == 0) "%A/bv\u
totalPage = totalRecords / everyPage; [LL"86D
else zO9$fU
totalPage = totalRecords / everyPage + 1 ; M_T$\z;,
7w@.)@5
return totalPage; [uc;M6o}?
} j
&,vju
5;>M&qmN
privatestaticboolean hasPrePage(int currentPage){ kzLj1Ix2
return currentPage == 1 ? false : true; kkyn>Wxv
} .m;1V6
WQv~<]1JF
privatestaticboolean hasNextPage(int currentPage, qOZc}J0
_S,2j_R9
int totalPage){ Mq[;:
return currentPage == totalPage || totalPage == 6 [a CjW
?j?{}Z
0 ? false : true; %a8'6^k
} C(}9
b\UQ6V
S?OK@UEJ
} s]5wzbF O
@K4} cP
@s/;y VVq
x\3 ` W
qoB
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。 ]B3 0d
MO9}Itg
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 xPQO}wKa
z\_q`43U7
做法如下: $SG^, !!&A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 qq[2h~6P]
}!Qo
wG
的信息,和一个结果集List: .3{S6#
java代码: d+fmVM?p
-R~;E[
{%
O7s0M?4
/*Created on 2005-6-13*/ #T#&qo#
package com.adt.bo; z.e%AcX
1
YMaUyL
1
import java.util.List;
SN?jxQ
Tl8S|Rg
import org.flyware.util.page.Page; e1~C>
z|+L>O-8
/** o7/_a/
* @author Joa ]'~'V2Ey
*/ 1^!=J<`K;
publicclass Result { |]+m<Dpyr2
Arir=q^2
private Page page; 0Hff/~J
mRj-$:}L
private List content; rU<
H7U
x:xKlPGd
/** Ad@))o2
* The default constructor eff6=DP
*/ ^._)HM
public Result(){ ~UK)
p;|
super(); 6x*ImhQ.J
} HQt=.#GW
M(b'4
/** MukPY2[Am
* The constructor using fields aNn < NW
* nLto=tNUO
* @param page >9+@oGe(E
* @param content ~K:#a$!%,
*/ ]hF[f|V
public Result(Page page, List content){ a=p3oh?%-O
this.page = page; pUwx`"DrR
this.content = content; ppb]RN|)
} wA.YEI|CSj
S;+bQ.
/** *N\U{)b\
* @return Returns the content. zclt2?
*/ ;lW0p8
publicList getContent(){ 0u'2f`p*
return content; TQE 3/I L
} \{{B57/Isq
zoC/Hm
/** >AN`L`%2
* @return Returns the page. Ulj2Py}
*/ i&mu=J[
public Page getPage(){ Z=825[p
return page; 5SR29Z[
} ;]Y.2 J
ZS >}NN
/** k-e_lSYk&c
* @param content /Wg$.<!5}
* The content to set. g@MTKqs
*/ {n$9o
public void setContent(List content){ eW\7X%I
this.content = content; e_k1pox]l
} fcnbPO0M
+c}fDrr)
/** T>vH ZZiO
* @param page Nf-IDK
* The page to set. 9y.C])(2
*/ g3LAi#m
publicvoid setPage(Page page){ N=tyaS(YJ
this.page = page; -$dnUXFsj[
} L)8;96
} S@N&W&W#~
3|9)A+,#
= ;dupz\7
{s=QwZdR
aina6@S
2. 编写业务逻辑接口,并实现它(UserManager, &IXr*I
sKn>K/4JZ
UserManagerImpl) JY9Hqf
java代码: e#FaK^V
sw{EV0&>m
`5[VO
/*Created on 2005-7-15*/ <gf:QX!
package com.adt.service; ?v8RY,Q30
~}83\LI}
import net.sf.hibernate.HibernateException; #^!oP$>1
RX?Nv4-
import org.flyware.util.page.Page; *|_u~v:)|5
9e=F
import com.adt.bo.Result; fJc,KZy
Gp;[WY\
/** il5WLi;{
* @author Joa kl3#&>e
*/ dE/Vl/ :
publicinterface UserManager { 5_G7XBvD/w
Qs#v/r
public Result listUser(Page page)throws ^a<=@0|
WAqR70{KM
HibernateException; isWB)$q
RL.%o?<&?
} L
G{N
?P{C=Td2z
N5%~~JRO
Be8Gx
@8n0GCv
java代码: Tk.MtIs)V}
cO)GiWE
?o9l{4~g
/*Created on 2005-7-15*/ _f^q!tP&d
package com.adt.service.impl; WDE_"Mm
<mrLld#_:C
import java.util.List; 9DKmXL
g@B9i=
import net.sf.hibernate.HibernateException; &[R&@l Y
(5_o H
import org.flyware.util.page.Page; [OH>NpL
import org.flyware.util.page.PageUtil; {\C$Bz
/YUf('b
import com.adt.bo.Result; x9-K}s]%
import com.adt.dao.UserDAO; wnt^WW=a[
import com.adt.exception.ObjectNotFoundException; if#$wm%
import com.adt.service.UserManager; -7m;rD4J
KGP2,U6
/** ScZ$&n
* @author Joa N;r,B
*/ rd%3eR?V
publicclass UserManagerImpl implements UserManager { oJyC{G
X=${`n%LG
private UserDAO userDAO; c7wza/r>
`1M_rG1/+
/** uZ<Bfrc
* @param userDAO The userDAO to set. ~g1@-)zYxK
*/ O=c&
publicvoid setUserDAO(UserDAO userDAO){ Axj<e!{D
this.userDAO = userDAO; m_\CK5T_
} RD{jYr;
=k3QymA
/* (non-Javadoc) m='+->O*'l
* @see com.adt.service.UserManager#listUser MW'z*r|,
/R9>\}.yJ
(org.flyware.util.page.Page) PcDPRX!@
*/ 7F}I.,<W
public Result listUser(Page page)throws rrbCg(
` Bkba:
HibernateException, ObjectNotFoundException { {oBVb{<
int totalRecords = userDAO.getUserCount(); Z U
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if(totalRecords == 0) 6u8`,&U
throw new ObjectNotFoundException (z^2LaM `8
(:-DuUt
("userNotExist"); [m}x
page = PageUtil.createPage(page, totalRecords); .Ddl.9p5
List users = userDAO.getUserByPage(page); *zz/U
(9D
returnnew Result(page, users); A{&Etu(K
} b*P\a
\f /<#'
} &(Xp_3PO
\Cx3^
iX
->8n.!F}
kE6\G}zj
&S3szhe
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @H7dQ,%
`I6)e{5t
询,接下来编写UserDAO的代码: !X[lNtO
3. UserDAO 和 UserDAOImpl: IO v4Zx<)
java代码: p)TH^87
'y'>0'et
c{FvMV2em
/*Created on 2005-7-15*/ >A2&
Mjo
package com.adt.dao;
Ge(r6"%7
P d*}0a~
import java.util.List; B<:i[~`7t
b!7"drge:
import org.flyware.util.page.Page; 2uiiTg>
xu&
v(C9
import net.sf.hibernate.HibernateException; J8/>b{Y
H(?z?2b p
/** u@==Ut
* @author Joa !aLByMA
*/ \ZCc~muR
publicinterface UserDAO extends BaseDAO { )o9CFhFB
/SN.M6~
publicList getUserByName(String name)throws i$%;z~#wW
63:ZDQ
HibernateException; S&.DpsK
G
V0q?
publicint getUserCount()throws HibernateException; XUW~8P
n6|}^O7
publicList getUserByPage(Page page)throws r}*2~;:pW
9H.E15B
HibernateException; u7a4taM$d
9%\q*
} 9dKrE_zK:
BMFpkK9|
I"<~!krt%
!u4oo-
Fp@eb8Pl
java代码: $XT&8%|*7
^IQC:21
-qx Z3
/*Created on 2005-7-15*/ Kj-:'jzW
package com.adt.dao.impl; D5AKOM!`
nSd?P'PFg
import java.util.List; X)~JX}-L
ly,d =
import org.flyware.util.page.Page; F_V~UX1D
/xf%Rp4}
import net.sf.hibernate.HibernateException; _NqEhf:8
import net.sf.hibernate.Query; "%>/rh2Iq
(VBoZP=W
import com.adt.dao.UserDAO; Q
v{q:=k
HC!$Z`}Y
/** RJBNY;0
* @author Joa C(W?)6?
*/ w ="I*7c@
public class UserDAOImpl extends BaseDAOHibernateImpl n"_EDb
wXNFL9F8
implements UserDAO { k}jH
~!)_3o
/* (non-Javadoc) : 2?i9F0_
* @see com.adt.dao.UserDAO#getUserByName /6L\`\g
3n6_yK+D
(java.lang.String) *h-nI=
*/ )5yZSdA
publicList getUserByName(String name)throws tQ=U22&7
Gi;eDrgj~
HibernateException { }Qg9l|
String querySentence = "FROM user in class 4P2)fLmc
$:mCyP<y
com.adt.po.User WHERE user.name=:name"; }.`ycLW'
Query query = getSession().createQuery . 1?AU6\
WOgbz&S?J
(querySentence); v\\Z[,dK
query.setParameter("name", name);
]9A9q<lZ
return query.list(); ]^aece
t
} -V4@BKI8
O \lt!p3F
/* (non-Javadoc) q[dls_
* @see com.adt.dao.UserDAO#getUserCount() 5^P)='0*
*/ w6#hsRq[C
publicint getUserCount()throws HibernateException { hnG'L*HooE
int count = 0; Z;??j+`Eo
String querySentence = "SELECT count(*) FROM 9>%f99n
v*3ezf\
user in class com.adt.po.User"; Lxd*W2$3_
Query query = getSession().createQuery ULQ*cW&;?
2}509X(*
(querySentence); P8;|>OLZ)
count = ((Integer)query.iterate().next )+cP8$n6L
| LfH,6
()).intValue(); ,v)@&1Wh:
return count; .sjM$#V=
} z@<`]
M;3uG/E\
/* (non-Javadoc) O'$:wc#
* @see com.adt.dao.UserDAO#getUserByPage xmq~:fcU=
^*}L9Ot~
(org.flyware.util.page.Page) M^+~r,D1u
*/ u49/LtB\
publicList getUserByPage(Page page)throws roL~r`f`
H#wn3O
HibernateException { m0un=>{
String querySentence = "FROM user in class 6!b9 6bV
6,s@>8n
com.adt.po.User"; \zgRzO'N
Query query = getSession().createQuery =%$ _)=}J
52-^HV
(querySentence); r=qb[4HiV
query.setFirstResult(page.getBeginIndex()) yuKfhg7
.setMaxResults(page.getEveryPage()); R.>/%o
return query.list(); "C}nS=]8m
} QLIm+)T
oOQnV(I
} $Ce`(/
JUwP<C[
(lEWnf=2h
7{<t]wQq
"&L<u0KHG
至此,一个完整的分页程序完成。前台的只需要调用 yUEUIPL
Kw925@W
userManager.listUser(page)即可得到一个Page对象和结果集对象 \]y$[\F>
JLc\KVmF
的综合体,而传入的参数page对象则可以由前台传入,如果用 9{ciD
"!&V
(AR-8
webwork,甚至可以直接在配置文件中指定。 fN t
Zf(ucAhL
下面给出一个webwork调用示例: 8]2S'mxE
java代码: #M{}Grg
0g`WRe
n6ud;jN|
/*Created on 2005-6-17*/ ,n&Dg58K
package com.adt.action.user; G7zfyw}W
C"hc.A&4
import java.util.List; WY<ip<
OEZXV ;F
import org.apache.commons.logging.Log; T[ky7\
import org.apache.commons.logging.LogFactory; /mqEc9sq,
import org.flyware.util.page.Page; gEPCXf
uOm fpg O
import com.adt.bo.Result; c;(}Ih(#
import com.adt.service.UserService; ;k!Ej-(
import com.opensymphony.xwork.Action; qYbod+UX
^#gGA_H
/** \n+`~< i
* @author Joa B>9D@fmzs
*/ 4my8 p Fk
publicclass ListUser implementsAction{ FC vR
Ur5X~a\y
privatestaticfinal Log logger = LogFactory.getLog J,P7k$t2vv
(K0FWTmm
(ListUser.class); :/
"qNPJ
,uDB]
private UserService userService; 64>Zr
+Uj~zx@
private Page page; !f_Kq$.{
Q.vtU%T
privateList users; z2 nDD6N
F>!fu.Ws
/* >Q"eaJxE!l
* (non-Javadoc) @GjWeOj]
* p/SJt0
* @see com.opensymphony.xwork.Action#execute() Q,)G_lO
*/ aD%")eP%&
publicString execute()throwsException{ X0P<ifIv
Result result = userService.listUser(page); C]eb=rw$
page = result.getPage(); L;grH5K5
users = result.getContent(); Pf(z0o&
return SUCCESS; AL,|%yup
} 7j._3'M=Kc
K$f~Fft
/** Av+R~&h
* @return Returns the page. O%
9~1_
*/ 97<Y.
0
public Page getPage(){ w[]7{D];
return page; INcJXlv
} U_oMR$/Z
l_QpPo!a
/** UI hB
* @return Returns the users. ]TD]
*/ !k%Vw18
publicList getUsers(){ wK|&[ms
return users; x!LUhX '
} P +oCcYp
]NsbV
/** s)&"ga
* @param page +| Cvv]Tx1
* The page to set. 2Ni2Gkf@
*/ =}_c=z?UY
publicvoid setPage(Page page){ *i)GoQoB
this.page = page; 0(
/eSmet
} [,G]#<G?q
`Mp]iD{
/** 8 rnr>Ee@
* @param users "f5u2=7 }
* The users to set. zBqr15
*/ 3$WK%"%T
publicvoid setUsers(List users){ N=:yl/M
this.users = users; !"p,9
} #YhKAG@|
saYn\o"m
/** ]3 Mm"7`
* @param userService F~<$E*&h@
* The userService to set. Q/0;r{@Tq}
*/ ezHj?@
publicvoid setUserService(UserService userService){ Nb(se*Y#
this.userService = userService; IKAF%0[R|j
} cUS2*7h
} `(Ei-$
>U&
ilpg()
N[zI@>x
42Ql^ka
qlDLZ.
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, sm\/wlbE
*/?L_\7
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 x{RTI#a.
X9zTz2 Fy
么只需要: >8jDW "Ua
java代码: 5M*q{kX)
ZhM-F0;`
y\)bxmC
<?xml version="1.0"?> 9lOUE
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 'Y>!xm
u4fTC})4{C
1.0//EN" "http://www.opensymphony.com/xwork/xwork- vjbot^W9
6U# C
1.0.dtd"> zKgW9j<(
LF{ qI?LG
<xwork> *1%=?:$(r6
P),%S9jP;
<package name="user" extends="webwork- NL2n\%n
Zw"6-h4
interceptors"> x"U/M?l
213D{#2
<!-- The default interceptor stack name
s9O] tk
9-p d{Z~l
--> :sM|~gT
<default-interceptor-ref ("mW=Ln
h7(twct
name="myDefaultWebStack"/> r_
r+&4n
2c9@n9Vx3a
<action name="listUser" {zmo7~=
ed*=p
l3.
class="com.adt.action.user.ListUser"> =ngu*#?c4
<param (|O;Ci
0qJ 3@d
name="page.everyPage">10</param> 69q8t*%O
<result N9{ivq|fO
[o|]>(tk
name="success">/user/user_list.jsp</result> ^k u~m5v
</action> hFQC%N.'
2NE/ZqREg
</package> -cIc&5CS
yf_<o
</xwork> QZQ@C# PR;
}R}tIC-:
HQ2in_'
I~4`NV0
bFJmXx&
w)DO"Z7
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 V<ODt%
T|9Yo=UK%
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 y]cx}9~
VVCCPK^<
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 MQR2UK(
VAq(
t
F
\} Kh3
z XVQLz5
@/|sOF;8W
我写的一个用于分页的类,用了泛型了,hoho Z(U&0GH`
;x+4jpH]B
java代码: TpMfk7-
?e&CbVc4
ub.pJJlC
package com.intokr.util; yu}4L'e
,{zvGZ|
import java.util.List; `EWeJ(4Z@
)Tb{O
/** 4p %`Lv
* 用于分页的类<br> S7N54X2JwL
* 可以用于传递查询的结果也可以用于传送查询的参数<br> @JN%P}4)
* )t)tk=R9N
* @version 0.01 dqd Qt_
* @author cheng B%'Np7
*/ ,9W 0fm\t
public class Paginator<E> { vi lNl|
privateint count = 0; // 总记录数 ,wZ[Y
3
privateint p = 1; // 页编号 xB9^DURr\
privateint num = 20; // 每页的记录数 7g(rJGjtg
privateList<E> results = null; // 结果 Hi.JL
>@]E1Qfe
/** ;'p0"\SV
* 结果总数 73N%_8DH
*/ nc$?tC9V
publicint getCount(){ 1d-j_H`s
return count; %NxNZe
} <NS=<'U
h"ZF,g;a
publicvoid setCount(int count){ d@#=cvW
this.count = count; 5'oWd
e
} *%8,G'"r?
%tQIKjsVaY
/** NK"y@)%0
* 本结果所在的页码,从1开始 QRt(?96
* }14.u&4
* @return Returns the pageNo. ]G|@F
:
*/ >E)UmO{S
publicint getP(){ I<[(hPQUf
return p; qn4Dm ^
} hA/FK
Q^0K8>G^
/** c}rRNS$F
* if(p<=0) p=1 ;{HxY98Q
* mP:mzmUw
* @param p 5HOhk"
*/ ;5 IS58L
publicvoid setP(int p){ X>*zA?:
if(p <= 0) G. <9K9K
p = 1; C'zMOR6c
this.p = p; tx5@r;
} gs0,-)
BB>7%~3f
/** #yU4X\oO
* 每页记录数量 +Pa!pj/< z
*/ ?]paAP;4
publicint getNum(){ Kz^aW
return num; @?gH3Y_
} k^ZUOWmU|
F}.Af=<Q
/** G%'h'AV"
* if(num<1) num=1 ]=]'*Z%
*/ -,XS2[
publicvoid setNum(int num){ oD"fRBS+$
if(num < 1) PT\5P&2o@
num = 1; >8>.o[Q&
this.num = num; !4*@H
} ^z)lEO
li; P,kg$
/** )Hev-C"
* 获得总页数 IXzad
*/ ,QKG$F
publicint getPageNum(){ [3/P
EDkw
return(count - 1) / num + 1; YK}(VF?&
} Qt@~y'O
zb;2xTH+
/** ;q$<]X_S)}
* 获得本页的开始编号,为 (p-1)*num+1 MTLcLmdO
*/ v,>q]!
|a
publicint getStart(){ sav2 .w
return(p - 1) * num + 1; );,#H`'
} -$T5@
u2Rmp4]
/** (:[><-h.
* @return Returns the results. zIdQ^vm8Q
*/ *>\RGL;]8
publicList<E> getResults(){ Z;%qpsq
return results; yM#W,@
} ?BWWb
3QXGbu}:h!
public void setResults(List<E> results){ 9&2kuLp?P
this.results = results; c6?5?_ne
} Gjv'$O2_
\Dt0
}
?;k
public String toString(){ *b.>pY?2|
StringBuilder buff = new StringBuilder ,eZ'pxt
L(8Q%oX%o
(); h\.UUC&<
buff.append("{"); +x+H(of.
buff.append("count:").append(count); "bw4{pa+
buff.append(",p:").append(p); x80~j(uVf
buff.append(",nump:").append(num); "`&?<82
buff.append(",results:").append ZS}2(t
k+s<;{
(results); Mq*Sp
UR
buff.append("}"); } [75`pC~O
return buff.toString(); c)Y I3G$
} b!`:|!7r'
;dB=/U>3U
} -iJ[9O
xQmk2S`
y
u
|f h!-