Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 o[T+/Ej&
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 8&)v%TX
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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 O,%,dtD[a
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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 =d<RgwscJ
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分页支持类: AQlB_@ b
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java代码: hPDKxYD]f
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package com.javaeye.common.util; xi=ApwNj
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import java.util.List; TZAd{EZa
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publicclass PaginationSupport { $/++afim
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publicfinalstaticint PAGESIZE = 30; DH-M|~.sf^
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privateint pageSize = PAGESIZE; ,vJt!}}
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privateList items; tcuwGs>_
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privateint totalCount; h'):/}JPl
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privateint[] indexes = newint[0]; _\}'5nmw\
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privateint startIndex = 0; ,Of^xER`
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public PaginationSupport(List items, int *?rWS"B
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totalCount){ YAr6cl
setPageSize(PAGESIZE); 8Xotly
setTotalCount(totalCount); QF#w$%7
setItems(items); wA=r]BT
setStartIndex(0); <(L@@.87R
} 4wl1hp>,
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public PaginationSupport(List items, int ;]>kp^C#
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totalCount, int startIndex){ p,Ff,FfH
setPageSize(PAGESIZE); 5Q?Jm~H9
setTotalCount(totalCount); $KiCs]I+
setItems(items); Oj5UG*
setStartIndex(startIndex); jT{T#_
} sgX!4wG&Z
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public PaginationSupport(List items, int LL^KZ-
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totalCount, int pageSize, int startIndex){ 8M,*w6P
setPageSize(pageSize); 4G c
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setTotalCount(totalCount); #z*,CU#S9d
setItems(items); H_DCdUgC'
setStartIndex(startIndex); K p3}A$uV
} tIsWPt]Y
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publicList getItems(){ CLR1CGnn7
return items; O
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} m[9.'@ye
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publicvoid setItems(List items){ >XD?zF)6
this.items = items; {3~VLdy
} ?\}Gi(VVE
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publicint getPageSize(){ _R4}\3}!
return pageSize; 9%!h/m>rW
} [GLH8R
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publicvoid setPageSize(int pageSize){ "yn~axk7
this.pageSize = pageSize; ;H_/o+
} Dyov}y
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publicint getTotalCount(){ ^X=Q{nB
return totalCount; y+k_&ss
} !#tVQ2O
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publicvoid setTotalCount(int totalCount){ $*yYmF
if(totalCount > 0){ /WrB>w
this.totalCount = totalCount; f98,2I(>`+
int count = totalCount / |3*9+4]a
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pageSize; sVLvnX,
if(totalCount % pageSize > 0) 9BCW2@Kp
count++; =kjKK
indexes = newint[count]; >rSjP1-F
for(int i = 0; i < count; i++){ (o^tmH*
indexes = pageSize * "HMEoZ
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i; 1|bXIY.J*
} ( ;FxKm<P@
}else{ DJP6Z
this.totalCount = 0; 2;}leZ@U
} ^|Ap_!t$;
} m5\T,
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publicint[] getIndexes(){ 0Y.z
return indexes; [BWq9uE
} 54
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publicvoid setIndexes(int[] indexes){ +>ju,;4WK
this.indexes = indexes; fqNh\~kja
} [GwAm>k
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publicint getStartIndex(){ A~zn;
return startIndex; t*{L[c9.Uq
} ,+=9Rp`md
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publicvoid setStartIndex(int startIndex){ %b6$N_M{H1
if(totalCount <= 0) _:x]'w%
this.startIndex = 0; 9^gYy&+>6]
elseif(startIndex >= totalCount) E
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this.startIndex = indexes BZq#OAp
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[indexes.length - 1]; ({f}Z-%
elseif(startIndex < 0)
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this.startIndex = 0; 9:j?Jvw$
else{ Ox3=1M0
this.startIndex = indexes k(gbUlCc
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[startIndex / pageSize]; }LHYcNw^z
} ^&zCPUH
} =|t-0'RsN
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publicint getNextIndex(){ MK&,2>m,A
int nextIndex = getStartIndex() + u[>"_!T
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pageSize; lZFu|(
if(nextIndex >= totalCount) Ln"wjO,
return getStartIndex(); ;kFD769DLw
else =|3BkmO
return nextIndex; "J VIkC
} m%'nk"p9
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publicint getPreviousIndex(){ q+g,?;Yx
int previousIndex = getStartIndex() - b--=GY))F
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pageSize; 0w?da~
if(previousIndex < 0) M4^G3c<
return0; ;Xy=;Z.]i
else dzBP<Xyh
return previousIndex; &b`W<PAc?4
} D4,>g )B
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} PkI+z_
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抽象业务类 as!a!1
java代码: (y 7X1Qc)
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/** W.?/p~
* Created on 2005-7-12 4k-Ak6s
*/ $\Y&2&1s
package com.javaeye.common.business; pITF%J@_]
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import java.io.Serializable; Pv/v=s>X
import java.util.List; *dw.Ug
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import org.hibernate.Criteria; C[G+SA1&W
import org.hibernate.HibernateException; |Rz.Pt6
import org.hibernate.Session; DegbjqZ#
import org.hibernate.criterion.DetachedCriteria; /De~K+w7o
import org.hibernate.criterion.Projections; GaG>0x
import 8>,w8(Nt
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org.springframework.orm.hibernate3.HibernateCallback; 3>-h-
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import #$-E5R;x
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org.springframework.orm.hibernate3.support.HibernateDaoS >#x[qX
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upport; 1QG q;6\
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import com.javaeye.common.util.PaginationSupport; y'`/^>.
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public abstract class AbstractManager extends 8zD>t~N2C
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HibernateDaoSupport { l^9gFp~I
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privateboolean cacheQueries = false; uW(-?
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privateString queryCacheRegion; v62_VT2v
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publicvoid setCacheQueries(boolean /oHCV0!0
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cacheQueries){ O*~z@"\
this.cacheQueries = cacheQueries; ;na%*G`
} < ,*\t
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publicvoid setQueryCacheRegion(String Z|uvrFa
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queryCacheRegion){ {uaDpRt
this.queryCacheRegion = GDL/5m#
() _RLA
queryCacheRegion; dA~:L`A|X
} iVI&
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publicvoid save(finalObject entity){ 05q760I+
getHibernateTemplate().save(entity); );7
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} [~s+,OO9)
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publicvoid persist(finalObject entity){ B2ln8NF#Q
getHibernateTemplate().save(entity); 0% rDDB
} Q+T#J9Y
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publicvoid update(finalObject entity){ Ak9{P`
getHibernateTemplate().update(entity); iY,C0=n5Y
} pT]hPuC
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publicvoid delete(finalObject entity){ E+@Q
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getHibernateTemplate().delete(entity); {Ya$Q#l
} Uz^N6q
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publicObject load(finalClass entity, cERIj0~
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finalSerializable id){ ?ZlXh51
return getHibernateTemplate().load h9H z6
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(entity, id); 5qtk#FB
} j%Au0k
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publicObject get(finalClass entity, ;`78h?`
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finalSerializable id){ 2d[q5p
return getHibernateTemplate().get @.eN+o9|
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(entity, id); Trv}YT.
} AOR?2u
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publicList findAll(finalClass entity){ Y\]ZIvTSb
return getHibernateTemplate().find("from )}@D\(/@
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" + entity.getName()); cAW}a
} Vke<; k-
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publicList findByNamedQuery(finalString dw"Es;^
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namedQuery){ `q*[fd1u.
return getHibernateTemplate =OHX5:Z
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().findByNamedQuery(namedQuery); _nMd
} 9Y:I)^ek
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publicList findByNamedQuery(finalString query, ZbYC3_7w
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finalObject parameter){ 9p W~Gz
return getHibernateTemplate 6R n?pe^
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().findByNamedQuery(query, parameter); H0af u)$,
} ~XTC:6ts
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publicList findByNamedQuery(finalString query, /mex{+p>tO
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finalObject[] parameters){ @|b-X? `
return getHibernateTemplate eP-|3$
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().findByNamedQuery(query, parameters); `}Zqmfs
} 5qz,FKx5
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publicList find(finalString query){ <1|[=$w
return getHibernateTemplate().find Tx;a2:6\[
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(query); ..)J6L5l
} $l]:2!R
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publicList find(finalString query, finalObject _i05'_
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parameter){ f$C{Z9_SX
return getHibernateTemplate().find EqW~K@
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(query, parameter); Ul}RT xJ
} k[r^@|
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public PaginationSupport findPageByCriteria keAoJeG,J
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(final DetachedCriteria detachedCriteria){ +fKOX#%
return findPageByCriteria U,=f};
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5#DMizv6
} bJ^h{]
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public PaginationSupport findPageByCriteria !D??Y^6bI
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(final DetachedCriteria detachedCriteria, finalint ukiWNF/
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startIndex){ F)^0R%{C
return findPageByCriteria :21d
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(detachedCriteria, PaginationSupport.PAGESIZE, ) D@j6r
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startIndex); ]fM|cN8(zM
} sW]_Ky.]
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public PaginationSupport findPageByCriteria :PO./IBX
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(final DetachedCriteria detachedCriteria, finalint 6("_}9ZOc
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pageSize, /|?$C7%a\D
finalint startIndex){ h&0zR#t
return(PaginationSupport) cC/h7odY
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getHibernateTemplate().execute(new HibernateCallback(){ &,&+p0CSI!
publicObject doInHibernate hXTfmFy{n
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(Session session)throws HibernateException { M"3"6U/ e
Criteria criteria = =[(34#
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detachedCriteria.getExecutableCriteria(session); j,0`k
int totalCount = )~U1sW&t
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((Integer) criteria.setProjection(Projections.rowCount Uy?jVPL
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()).uniqueResult()).intValue(); yK*vn]}
criteria.setProjection x92^0cMf
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(null); f'*-<sSr
List items = !&:=sA
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criteria.setFirstResult(startIndex).setMaxResults *vb"mB
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(pageSize).list(); ,Z{\YAh1
PaginationSupport ps = 8b/$Qp4d
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new PaginationSupport(items, totalCount, pageSize, [IYVrT&C'
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startIndex); :33@y%>L
return ps; @Xo*TJB
} PT/Nz+
}, true); CFbNv9GZj
} c-+NWC
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public List findAllByCriteria(final =D1
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DetachedCriteria detachedCriteria){ v=llg ^
return(List) getHibernateTemplate @v)Z>xv
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().execute(new HibernateCallback(){ [^hW>O=@TN
publicObject doInHibernate y7HFmGM
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(Session session)throws HibernateException { ~gI%lORqN
Criteria criteria = NEq_!!/sF
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detachedCriteria.getExecutableCriteria(session); dtTn]}J
return criteria.list(); 3TwjC:Yhv2
} VF?H0}YSHb
}, true); '/>Mr!H#
}
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public int getCountByCriteria(final CS[]T9|_
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DetachedCriteria detachedCriteria){ a/J<(sak~X
Integer count = (Integer) :c*"Dx'D
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getHibernateTemplate().execute(new HibernateCallback(){ rq%]CsRY5
publicObject doInHibernate zhn?;Fi
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(Session session)throws HibernateException { w#.3na
Criteria criteria = "Z@P&jl
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detachedCriteria.getExecutableCriteria(session);
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return Tz,-~ mc
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criteria.setProjection(Projections.rowCount ;<+efYmyc
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()).uniqueResult(); X$kLBG[o_
} ~~>m
}, true); p(F@lL-
return count.intValue(); b<W\#3~G
} ktyplo#F
} i~u4v3r=
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用户在web层构造查询条件detachedCriteria,和可选的 I\)`,w
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 A?YYR%o%'
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PaginationSupport的实例ps。 Jm4uj&}3
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ps.getItems()得到已分页好的结果集 I!/32* s1t
ps.getIndexes()得到分页索引的数组 zhJeTctRz
ps.getTotalCount()得到总结果数 PD&e6;rj;
ps.getStartIndex()当前分页索引 HoQb.Z
ps.getNextIndex()下一页索引 D6ZHvY8R
ps.getPreviousIndex()上一页索引 A]bb*a1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r5j$FwY
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 S1=P-Ao
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一下代码重构了。 ,6+joKe-
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我把原本我的做法也提供出来供大家讨论吧: DAw1S$dM
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首先,为了实现分页查询,我封装了一个Page类: I9kz)Q o
java代码: Dl>tF?=
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/*Created on 2005-4-14*/ hb3n-
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package org.flyware.util.page; k+_>`Gre}
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/** ? 2}%Rb39
* @author Joa S?v/diK ]J
* )G48,.
"
*/ <)d%c%f'`
publicclass Page { "~Fg-{jM%
INndTF
/** imply if the page has previous page */ #Y= A#Yz,{
privateboolean hasPrePage; S.MRL,
j~'.XD={
/** imply if the page has next page */ Hzz{wY
privateboolean hasNextPage; "ku[b\W
H&s`Xr
/** the number of every page */ 9~V'Wev
privateint everyPage; !*l /Pr^8
}Y-V!z5z!
/** the total page number */ s#7"ZN
privateint totalPage; #IH9S5B [
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/** the number of current page */ |lhnCShw
privateint currentPage; (MXy\b<
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/** the begin index of the records by the current xh;gAh5n
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query */ !oyo_h
privateint beginIndex; 0Y oKSo
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Mmz;
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/** The default constructor */ her>L3G-E
public Page(){ 3nA^s"#p
#ed|0
} sm18u-
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/** construct the page by everyPage u-~ec{oBu
* @param everyPage DVd8Ix <
* */ ";.j[p:gi
public Page(int everyPage){ Hec8pL
this.everyPage = everyPage; WSpF/Wwc
} %Za}q]?
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/** The whole constructor */ )B]"""J
public Page(boolean hasPrePage, boolean hasNextPage, wXQu%F3
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int everyPage, int totalPage, mX|M]^_,z
int currentPage, int beginIndex){ J *LPv9)
this.hasPrePage = hasPrePage; L\mF[Kd#+T
this.hasNextPage = hasNextPage; ?EUg B\
this.everyPage = everyPage; j+3\I>
this.totalPage = totalPage; EI=~*&t
this.currentPage = currentPage; ";U~wZW_
this.beginIndex = beginIndex; aH;AGbp
} ]Q FI>
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/** dg.1{6HM
* @return [xGwqa03
* Returns the beginIndex. gI7*zR4D
*/ o;c"-^>
publicint getBeginIndex(){ (pH)QG
return beginIndex; {n>.Y-=
} 8`S1E0s
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/** =b66H]h?
* @param beginIndex XrUI[ryE
* The beginIndex to set. .?:#<=1
*/ Q>L(=j2t
publicvoid setBeginIndex(int beginIndex){ [%^0L~:
this.beginIndex = beginIndex; QE/kR!r
}
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/** M*k,M=sX
* @return VMABj\yG
* Returns the currentPage. Uic
*/ aMu6{u6
publicint getCurrentPage(){ gjsks(x
return currentPage; e<+)IW:
} E3a^"V3p
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/** ,|O6<u9
* @param currentPage T}J)n5U}\
* The currentPage to set. BoT#b^l
*/ Yv=L'0K&
publicvoid setCurrentPage(int currentPage){ :UT\L2 q=
this.currentPage = currentPage; U
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} OfrzmL<K
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/** $<nD-4p
* @return O!>#q4&]
* Returns the everyPage. xVsI#`<a
*/ h% >ZN-K)
publicint getEveryPage(){ #Ey_.4S
return everyPage; ,fiV xn Q
} qJ5b;=
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/** uj)vh
* @param everyPage Iep_,o.Sk
* The everyPage to set. u~,hTY(%
*/ 0B[~j7EGO
publicvoid setEveryPage(int everyPage){ V.8Vy1 $
this.everyPage = everyPage; gs+nJ+b
} H|e7IsY%
4-HBXG9#/
/** j0"4X
* @return 3 }sy{Mx%9
* Returns the hasNextPage. fP
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*/ ]Ky`AG`2~
publicboolean getHasNextPage(){ N MkOx$
return hasNextPage; TP| ogF?
} x?rd9c
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/** =,6X_m
* @param hasNextPage },X.a@:
* The hasNextPage to set. ^d#
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*/ Uo9@Y{<B
publicvoid setHasNextPage(boolean hasNextPage){ @ o<OI
this.hasNextPage = hasNextPage; [g`4$_9S
} <8~c7kT'
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/** L{1[:a)']B
* @return $ r-rIW5\
* Returns the hasPrePage. djoP`r
*/ 'w1ll9O
publicboolean getHasPrePage(){ 'k}w|gNB
return hasPrePage; A|PZ<WAY
} %qqCpg4
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/** 8LF=l1=~
* @param hasPrePage %x;~o:
* The hasPrePage to set. zrA3bWs
*/ yD$d^/:
publicvoid setHasPrePage(boolean hasPrePage){ 'Sgz\=K
this.hasPrePage = hasPrePage; CXuMNa
} s(Wys^[g
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/** nm_taER
* @return Returns the totalPage. /?j
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* jT]R"U/Q
*/ ?N9Z;_&^.
publicint getTotalPage(){ XL44pE
m
return totalPage; `c^">L
} InRRcn(
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/** h'GOO(
* @param totalPage uwi.Sg11
* The totalPage to set. 4Q1R:Ra
*/ ,ExY.'%1
publicvoid setTotalPage(int totalPage){
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this.totalPage = totalPage; Jq"3xj
} !K2QD[x
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} GBBp1i
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 '
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个PageUtil,负责对Page对象进行构造: (+xT5 2
java代码: mBB"e"o
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/*Created on 2005-4-14*/ NU'2QSU8
package org.flyware.util.page; \R-'<kN.*
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import org.apache.commons.logging.Log; U|QP]6v
import org.apache.commons.logging.LogFactory; q-@&n6PEOZ
p Djt\R<f
/** y\CxdTs
* @author Joa -s)h
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* wSM(!:on5
*/ B+jh|@-
publicclass PageUtil { 8$ RiFD,
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privatestaticfinal Log logger = LogFactory.getLog $Fi1Bv)
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(PageUtil.class); +Y;hVcE9
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/** &Cm]*$?
* Use the origin page to create a new page Hj `\Fm*A
* @param page m;1/+qs0
* @param totalRecords 9s7TLT k
* @return N9*QQ0
*/ I\M
}Dxpp
publicstatic Page createPage(Page page, int ]Nssn\X7
;bHS^
totalRecords){ QX&Y6CC`]
return createPage(page.getEveryPage(), @KHY8y7
o!&+ _BKw
page.getCurrentPage(), totalRecords); Vo.~1^
} fo~*Bp()-E
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/** UUvCi+W
* the basic page utils not including exception bVa?yWb.
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handler 6]?W&r|0I
* @param everyPage K W
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* @param currentPage `}L{gssv
* @param totalRecords )J+A2>
* @return page ~J#Z7y]p!j
*/
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publicstatic Page createPage(int everyPage, int z
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currentPage, int totalRecords){ <$Sl%DoS
everyPage = getEveryPage(everyPage); O.\\)8xA
currentPage = getCurrentPage(currentPage); 4#:Eq=(W
int beginIndex = getBeginIndex(everyPage, 19[!9ci
MZWv#;.]
currentPage); 8^_e>q*W
int totalPage = getTotalPage(everyPage, p&4n"hC
<5#2^ (
totalRecords); nz#eJ
boolean hasNextPage = hasNextPage(currentPage, T-+ uQ3
qUn+1.[%
totalPage); .LnknjC
boolean hasPrePage = hasPrePage(currentPage); 5:5d=7WX
^
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returnnew Page(hasPrePage, hasNextPage, <Ter\o5%
everyPage, totalPage, ][#|5UK8L
currentPage, .RAyi>\e
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beginIndex); ]n"U])pJd
} ( *K)D$y
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privatestaticint getEveryPage(int everyPage){ M)Z!W3
return everyPage == 0 ? 10 : everyPage; x;/dSfv_
} 8TU(5:xJo
K:Z(jF!j
privatestaticint getCurrentPage(int currentPage){ Oz&*A/si+3
return currentPage == 0 ? 1 : currentPage; >pJ#b=
} jffNA^e
0jPUDkH*
privatestaticint getBeginIndex(int everyPage, int ^ZRZ0:rZ
GZn=Hgv8
currentPage){ K_:2sDCaN
return(currentPage - 1) * everyPage; 5j0 Ib>\
} Fq
oh!F
}s6Veosl
privatestaticint getTotalPage(int everyPage, int |YV> #l
e"{"g[b/7
totalRecords){ {^:NII]
int totalPage = 0; EQw7(r|v:
Di}M\!-[
if(totalRecords % everyPage == 0) F?cwIE\J
totalPage = totalRecords / everyPage; =*zde0T?l
else Q7d@+C
totalPage = totalRecords / everyPage + 1 ; &"27U
_V0%JE'
return totalPage; D:z_FNN
} R?tjobk!
+ 660/ e8N
privatestaticboolean hasPrePage(int currentPage){ UlNV%34"
return currentPage == 1 ? false : true; mI:^lp
} M`@AS L:u
Qgv g*KX
privatestaticboolean hasNextPage(int currentPage, D/;[x{;E
YTTij|(
int totalPage){ G-R83Orl
return currentPage == totalPage || totalPage == 8|L@-F
pjoyMHWK
0 ? false : true; loE;q}^
} esQ`6i
K@*4=0
.c @Y?..+
} G K3T w
kg7bZ
'.>y'=
gN73)uJ0
D`'Cnt/
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。 Br42Qo2"T>
VN\VTSZh?\
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 rl$"~/ oz
@$;8k }
做法如下: =VT\$
5A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Qnt9x,1m_
#Q-#7|0&
的信息,和一个结果集List: 7sWe32
java代码: |-S+ x]9
'O.f}m SS
Iu5 9W>
/*Created on 2005-6-13*/ 8t)gfSG
package com.adt.bo; 1w7XM0SHcn
%B1)m A;
import java.util.List; "M\rO!f:
_O11SiP]
import org.flyware.util.page.Page; d<HO~+9
jAv3qMQA
/** HvKdV`bz
* @author Joa
4~ L1~Gk
*/ ^w"hA;
publicclass Result { Hvy$DX|p
B9KBq$e
private Page page; o2hZ=+w>
7'Hh^0<
private List content; #b:YY^{g_
gu~R4@3
/** u2`j\
Vu
* The default constructor x*=m'IM[
*/ @uN+]e+3
public Result(){ >H5t,FfQL
super(); ocMTTVo
} v0=v1G*rvJ
c#1kg@q@
/** ~RwoktO
* The constructor using fields suW|hh1/Ya
* )C{20_
* @param page 7#oq|5
* @param content V[]Pya|s+
*/ 8O60pB;4
public Result(Page page, List content){ 8bs' Ek{'o
this.page = page; kumo%TXB&
this.content = content; RP[`\
} &5bIM>)v
ubVZEsoW?
/** r[7*1'.p
* @return Returns the content. w6Mv%ZO_
*/ *a{WJbau]
publicList getContent(){ /!p}H'jl
return content; f;,*P,K
} 0blbf@XA
>T0`( #Lm
/** #(+V&<K
* @return Returns the page. z_{_wAuY
*/ /"~UGn]R
public Page getPage(){ t pxk8Ys
return page; ]EQ*!
} o:4#AkS
'`W6U]7>
/** dShGIH?
* @param content a gL@A
* The content to set. \ZE=WvnhZ
*/ $ZB`4!JxG
public void setContent(List content){ W* v3B.
this.content = content; -'*<;]P+.
} 01RW|rN
"K+EZ%~<
/** \&Bdi6xAy
* @param page *1_Ef).
* The page to set. ,zK E$
*/ g\IwV+iDf
publicvoid setPage(Page page){ rp[3?-fk
this.page = page; ^7;s4q
} $2}%3{<j
} EUV8H}d5
x1E;dbOZ
0XqxW\8_l
44YKS>Cq
#ZnNJ\6
2. 编写业务逻辑接口,并实现它(UserManager, |*-<G3@
<viC~=k;
UserManagerImpl) H(M{hfa|
java代码: m"'`$ /_
+~y>22Zfg
#<u;.'R
/*Created on 2005-7-15*/ Ra
H1aS(
package com.adt.service; 88?O4)c
)24M?R@r
import net.sf.hibernate.HibernateException; jPZpJ:
;mwnAO
import org.flyware.util.page.Page; puMbB9)
iY&I?o!Ch
import com.adt.bo.Result; E8p,l>6(f
Mk+G(4p
/** Unb3
Gv#O
* @author Joa rQ U6*f
*/ %9S0!h\
publicinterface UserManager { 5)h fI7{d
=]"I0G-s!
public Result listUser(Page page)throws |z:4T%ES
WNQ<XBqAw
HibernateException; kl9~obX
1
_./s[{ek
} {I?)ODx7qC
HXZ,"S
O.xtY@'"
u-mD"
kBoQjOV`
java代码: %*Uc,V
h@(+(fVHrp
?~yJ7~3TS<
/*Created on 2005-7-15*/ 5wl;fL~e
package com.adt.service.impl; #5'&
|<
``6-
import java.util.List; Nv6"c<(L=
<dr2 bz
import net.sf.hibernate.HibernateException; D&~%w!
@';.$
import org.flyware.util.page.Page; Aq3\Q>klH)
import org.flyware.util.page.PageUtil; &Vgpv#&Cfx
g0B%3v
import com.adt.bo.Result; G|8>Q3D
import com.adt.dao.UserDAO; QgQ$>
import com.adt.exception.ObjectNotFoundException; }@tgc?CD
import com.adt.service.UserManager; =]/<Kd}A.
kY{$[+-jR
/** >s0![c oz
* @author Joa i27)c)\BM
*/ b`^Q ':^A
publicclass UserManagerImpl implements UserManager { :g^
mg-8
TOS'|xQ
private UserDAO userDAO; dh&>E
[+xsX*+
/** HiH<'m"\.
* @param userDAO The userDAO to set. PB8g4-?p6
*/ n+YUG
publicvoid setUserDAO(UserDAO userDAO){ ecQ,DOX|b
this.userDAO = userDAO; 10OkrNQ
}
uKvdL
"
X;l/D},.
/* (non-Javadoc) kLU-4W5t
* @see com.adt.service.UserManager#listUser V'MY+#
yBIX<P)vE'
(org.flyware.util.page.Page) yTZo4c"
*/ cF8 X
public Result listUser(Page page)throws Q[K)Yd
[ ;sTl~gC
HibernateException, ObjectNotFoundException { < *;GJ{
int totalRecords = userDAO.getUserCount(); jvL!pEC!
if(totalRecords == 0) 9n;6zVV%`
throw new ObjectNotFoundException 5$cjCjY
w-LENdw
("userNotExist");
:2,NKdD
page = PageUtil.createPage(page, totalRecords); h0g?=hJq
List users = userDAO.getUserByPage(page); /S1/ ZI
returnnew Result(page, users); 5s`r&2 w
} )7o?}"I
h,]VWG
}
[)~1Lu
v}d)uPl};
G'PZ=+!XO/
NVsaV;u
~T-uk
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ar}-~~h 5
>8=lX`9f{
询,接下来编写UserDAO的代码: 0.w7S6v|&
3. UserDAO 和 UserDAOImpl: UOl*wvy
java代码: n_9Ex&?e
72yJv=G
QHf&Z*Xtl
/*Created on 2005-7-15*/ LyWY\K a
package com.adt.dao; *pv<ZF0>
q^Oj/ws
import java.util.List; dIYf}7 P
9!W$S[ABRB
import org.flyware.util.page.Page; xy"'8uRi
$/;K<*O$
import net.sf.hibernate.HibernateException;
xz.Jmv
m|c[C\)By
/** vgD+Y
* @author Joa GQ7uxdqWBQ
*/ ~?HK,`0h>
publicinterface UserDAO extends BaseDAO { U&Vu%+B
qIsf!1I?
publicList getUserByName(String name)throws 6L$KMYHE
4"(rZWv
HibernateException; Ddpcov
,qv\Y]
publicint getUserCount()throws HibernateException; L~Peerby
s-PS]l@
publicList getUserByPage(Page page)throws kmc"`Ogotw
"#E<Leh'
HibernateException; /W BmR R
~~-VScG&
} h@G~'\8t
LSJ.pBl\X
tO:JB&vO2
vszm9Qf
HdB>CVuh
java代码: sVw:d_ E
!3Pmjip
Z/ jmi
/*Created on 2005-7-15*/ ?{^_z_,
package com.adt.dao.impl; -mG`* 0
2HN*j~>i~
import java.util.List; Bps%>P~.
a{hc{
import org.flyware.util.page.Page; Hxgc9Fis
Q+9:]Bt
import net.sf.hibernate.HibernateException; |.0~'
import net.sf.hibernate.Query; ~nfOV*
86Q3d%;-yo
import com.adt.dao.UserDAO; 2J&~b 8 :
>WDHRC
/** kex V~Q
* @author Joa e7xBi!I)~
*/ 3,{eH6,O7M
public class UserDAOImpl extends BaseDAOHibernateImpl ,S=[#
rD SYR\cg
implements UserDAO { 9|Jv>Ur=)2
&TQ~!ZMOR"
/* (non-Javadoc) il@>b
* @see com.adt.dao.UserDAO#getUserByName 8TeOh1\
,mp<<%{u
(java.lang.String) /[FDiJH2
*/ Qa )+Tv
publicList getUserByName(String name)throws k!0O[U
g}D)MlXRq
HibernateException { nco.j:
String querySentence = "FROM user in class L4m Vk
4i)5=H
com.adt.po.User WHERE user.name=:name"; /ta}12Z
Query query = getSession().createQuery A%W]XEa<
bkDVW
(querySentence); :QGo
-,6-
query.setParameter("name", name); {&IB[Y6
return query.list(); ;98b SR/
} JpC=ACF
TsK!36cg
/* (non-Javadoc) X_o#!
* @see com.adt.dao.UserDAO#getUserCount() iv *$!\Cd
*/ @NRN#~S,_]
publicint getUserCount()throws HibernateException { $5JeN{B
int count = 0; W{"sB:E
String querySentence = "SELECT count(*) FROM ?I[8rzBWU
$ItmYj.m
user in class com.adt.po.User"; D0FX"BY7
Query query = getSession().createQuery Bc"MOSV0
W4^zKnH
(querySentence); [:cD
count = ((Integer)query.iterate().next ;kk[x8$
& mO n]
()).intValue(); rAu%bF
return count; -!1=S: S
} <.n,:ir
D :U6r^c
/* (non-Javadoc) rC^5Z
* @see com.adt.dao.UserDAO#getUserByPage :kR>wX
c#{lXS^
(org.flyware.util.page.Page) =6Ok4Z
*/ H}F
UgA;
publicList getUserByPage(Page page)throws SZ9Oz-?
>^jBE''
HibernateException { $45|^.b
String querySentence = "FROM user in class l'EO@D/M
]i.N'O<p
com.adt.po.User"; QX<n^W
Query query = getSession().createQuery @-dGZ5
0>BxS9?w
(querySentence); qhxMO[f
query.setFirstResult(page.getBeginIndex()) hi!A9T3%}M
.setMaxResults(page.getEveryPage()); >fXtu:C-!J
return query.list(); qKfUm:7Q_
} :6nD "5(
qhGz2<}_j
} _HHvL=
#kM|!U=
Xs052c|s
kJ5z['4?
^^"zjl*^
至此,一个完整的分页程序完成。前台的只需要调用 ~-A"j\gi"
UF!qp
userManager.listUser(page)即可得到一个Page对象和结果集对象 d*d:-f~q
LRu,_2"
的综合体,而传入的参数page对象则可以由前台传入,如果用 r89AX{:
/&Oo)OB;
webwork,甚至可以直接在配置文件中指定。 l|WFS
i|1*bZ6'
下面给出一个webwork调用示例: %Z_O\zRqy)
java代码: U_*,XLU
n>, :*5"G
'M~`IN`
/*Created on 2005-6-17*/ "Wg,]$IvU
package com.adt.action.user; TxPFl7,r
&RZO\ZT
import java.util.List; ) 1AAL0F\B
F9j@KC(yg
import org.apache.commons.logging.Log; -H6[{WVW!
import org.apache.commons.logging.LogFactory; m~
ah!QM
import org.flyware.util.page.Page; bHG<B
v-z%3x.f
import com.adt.bo.Result; Ih:Q}V#6
import com.adt.service.UserService; wH o}wp
import com.opensymphony.xwork.Action; 1;( h0j
JW[6
^Rw
/** D-BT`@~l
* @author Joa RdPk1?}K
*/ i4|R0>b
publicclass ListUser implementsAction{ EU[eG^/0@
dB_0B.
privatestaticfinal Log logger = LogFactory.getLog J]TqH`MA
_l7_!Il_
(ListUser.class); ({j8|{)+
rgVRF44X{
private UserService userService; P$U"y/
H\QkU`b
private Page page; W\zZ&*8$
J~5V7B
privateList users; MMFg{8
G*N[t w
/* `Qo37B2
* (non-Javadoc) t\ oud{Cv
* I%J>~=]n_
* @see com.opensymphony.xwork.Action#execute() z+yq%O
*/ kZG .Id
publicString execute()throwsException{ ?) y}HF
Result result = userService.listUser(page); a|z-EKV
page = result.getPage(); v]( Y n)#
users = result.getContent(); eI$V2
return SUCCESS; Z>`\$1CI
} N~=I))i
y-3'qq'E
/** *Mhirz%iD
* @return Returns the page. ~".@mubt1$
*/ I.3~ctzu
public Page getPage(){ V,rc&97
return page; -E?:W`!
} [bHm-X]
~g=&wT11
/** SQ,-45@W
* @return Returns the users. 06]3+s{{
*/ E'aOHSAg
publicList getUsers(){ X\Bl?
F
return users; .hmeP
MK
} aPelt`
f8lyH'z0
@
/** !s-A`}
s+
* @param page tG$O[f@U6
* The page to set. [gBf1,bK
*/ 2%WeB/)9
publicvoid setPage(Page page){ &"%Ws{Qn]
this.page = page; 7=Muq]j2
} -E|"?
QWOPCoUet
/** <5E'`T
* @param users z)C}}NH*!@
* The users to set. #4m5I="
*/ VF2,(f-*
publicvoid setUsers(List users){ IRQtA
Z V$
this.users = users; i) e6U(H
}
~frsgHW
68z#9}
/** Sqn>L`Lz
* @param userService ?IAu,s*u
* The userService to set. "yw{A%J
*/
<)TIj6
publicvoid setUserService(UserService userService){ qkhre3
this.userService = userService; s8,YQ5-
} }oZ8esZU2
} AF#:*<Ev
ysOf=~1
[nxYfER7
*Vl#]81~
clU ?bF~e1
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, my A;Y
y7UU'k`
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 8j>V?'Szk
S} UYkns*
么只需要: 1!^BcrG.
java代码:
#tKks:eL
:'bZ:J>f
/}@F
q
<?xml version="1.0"?> zY\u"
'4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork PFp!T [)
IQ<G.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9!jF$
I+
|uyc
1.0.dtd"> d\#yWY
AVjRhe
<xwork> 9R$$(zB 1;
m~Pk]~j
<package name="user" extends="webwork- ~:JAWs$\V
bji#ID2]%
interceptors"> {oY"CZ2
>Y4^<!\v
<!-- The default interceptor stack name E}4{{{r
lknj/i5L
--> %BC%fVdP
<default-interceptor-ref E?+~S M1~
K{_~W yRF
name="myDefaultWebStack"/> S=P}Jpq?Y;
WILa8"M
<action name="listUser" h
i!K-_Uy
*66EkCj
class="com.adt.action.user.ListUser"> a.<XJ\
<param {BlTLAKm
s7yKxg+`{
name="page.everyPage">10</param> (KC08
<result fwt+$`n
?jMM@O`Nu
name="success">/user/user_list.jsp</result> !7\dr )
</action> 9QP=
h:bx0:O"
</package> s;P _LaIp)
}BS
EK<W
</xwork> (+v':KH3_
7a9">:~
D>jtz2y=D
Ch?yk^cY
iyCH)MA
x=rMjz-`_
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 EB&hgz&_
Ijiw`\;
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。 1^o})9
N_:!uR
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Lfx a^0
e6'0g=Y#
e;=R8i
l1zPL3"u_^
*H/)S 5
我写的一个用于分页的类,用了泛型了,hoho a`yCPnB(
4;~xRg;u&*
java代码: ww
%c+O/
DOtz
H$?MPA-c
package com.intokr.util; W:<2" &7
g&/lyQ+G
import java.util.List; "n3n-Y#'
#vK99S2
/** EIzTbW{p
* 用于分页的类<br> e?(4lD)d
* 可以用于传递查询的结果也可以用于传送查询的参数<br> O~8jz
* Wp
=
]YO
* @version 0.01 dj084q7
* @author cheng 3U?gw!M>
*/ W!el[@
public class Paginator<E> { G:+D1J]
privateint count = 0; // 总记录数 zz3{+1w]
privateint p = 1; // 页编号 B[sI7D>Y
privateint num = 20; // 每页的记录数 @&HLm^j2O
privateList<E> results = null; // 结果 85"Szc-#
H '5zl^8I
/** -"yma_
* 结果总数 /tkV/
*/ b6e2a/x
publicint getCount(){ HHyN\
return count; vKoQ!7g
} -;Mh|!yg
MIr[_
publicvoid setCount(int count){
1^hG}#6_
this.count = count; s;<]gaonB_
} rr1,Ijh{D
F'<XB~&o
/** 7zQGuGo(
* 本结果所在的页码,从1开始 l66 QgPA
* 4t*VI<=<[
* @return Returns the pageNo. w'i+WEU>l
*/ BThrv$D}
publicint getP(){ F$v ^S+Ch
return p; cPL6(&7
} l}S96B
s Fk{Tv@Yz
/** J'#o6Ud
* if(p<=0) p=1 SPTx-b[
* =`}|hI
* @param p <vg|8-,#m
*/ NSRY(#3
publicvoid setP(int p){
+;@R&Y
if(p <= 0) ak}ke
p = 1; 2MXg)GBcU>
this.p = p; R,!aX"]|
} _B4N2t$
L eUp!
/** q2Gm8>F1y.
* 每页记录数量 0n{+_
*/ H5FWk
publicint getNum(){ S2I{?y&K
return num; >r:z`^p
} 4[r:DM|8
IQ#Kod;)
/** #)DDQ?D
* if(num<1) num=1 t]t(/x#
*/ <ihJp^kgQ
publicvoid setNum(int num){ BW`Tw^j
if(num < 1) p)7U%NMc(*
num = 1; Fvv/#V^R
this.num = num; O St~P^1
} #R=6$
g>?,,y6/w
/** &fxyY(
* 获得总页数 on\ahk, y]
*/ jA3Ir;a
publicint getPageNum(){ <UwA5X`0e.
return(count - 1) / num + 1; *q1sM#;5
} KH$o X\v
dr=KoAIxy
/** .GDY
J9vi
* 获得本页的开始编号,为 (p-1)*num+1 DQ6pe)E|
*/ lt l(SIi
publicint getStart(){ +P*,i$MV
return(p - 1) * num + 1; y9GaxW*&