Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 W
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 -Rhxib|<
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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 )p>BN|L
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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 :2?J#/o
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分页支持类: dZm>LVjG
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java代码: FS r`Y
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package com.javaeye.common.util; C_?L$3 U0
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import java.util.List; lNQ t
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publicclass PaginationSupport { 3uCC_Am
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publicfinalstaticint PAGESIZE = 30; fR}|CP
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privateint pageSize = PAGESIZE; ;"\e
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privateList items; WEUr;f
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privateint totalCount; ^ q @.yL
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privateint[] indexes = newint[0]; /] ce?PPC
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privateint startIndex = 0; {Q?AIp6u|
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public PaginationSupport(List items, int UXoaUW L
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totalCount){ }-k<>~FA
setPageSize(PAGESIZE); @0?Mwy!
setTotalCount(totalCount); Rk56H
setItems(items); f.rz2)o
setStartIndex(0); ;RW!l pGjP
} ;14[)t$
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public PaginationSupport(List items, int FZz\zp
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totalCount, int startIndex){ _L(6F
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setPageSize(PAGESIZE); -*k%'Gr
setTotalCount(totalCount); #Oz<<G<
setItems(items); g/W<;o<v(I
setStartIndex(startIndex); cUaLv1:HI
} R~CQ=KQ.
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public PaginationSupport(List items, int Gk*Mx6|N
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totalCount, int pageSize, int startIndex){ x
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setPageSize(pageSize); eP|:b &
setTotalCount(totalCount); FD*`$.e3\
setItems(items); >IC.Zt@
setStartIndex(startIndex); bT*MJ7VVm
} S&8gZ~B
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publicList getItems(){ xaX3<V@S
return items; [ECSJc&i
} @$gvV]dA
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publicvoid setItems(List items){ %F9%t
this.items = items; zFqH)/
} &4sUi K"
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publicint getPageSize(){ AQU4~g
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return pageSize; "2)<'4q5)
} QQ!%lbMK]
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publicvoid setPageSize(int pageSize){ cfMj^*I
this.pageSize = pageSize; uI@:\Rss
} FEw51a+V
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publicint getTotalCount(){ Ku*@4#<L6h
return totalCount; !]&a/$U
} OljUK,I]
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publicvoid setTotalCount(int totalCount){ bdk"7N
if(totalCount > 0){ vUR{!`14
this.totalCount = totalCount; Gn#5zx#l
int count = totalCount / 5Az=)q4Q
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pageSize; q-eC=!#}
if(totalCount % pageSize > 0) k/=J<?h0
count++; .%<oy"_
indexes = newint[count]; X{P_HCd
for(int i = 0; i < count; i++){ #+|{l*>
indexes = pageSize * !>Db
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i; DGj:qd(
} n'v[[bmu
}else{ [MdVgJ9'
this.totalCount = 0; HvN!_}[
} O9oYuC :q
} 28C/^4
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publicint[] getIndexes(){ X,:^})]
return indexes; Mi,yg=V
} D5Wo e&g,
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publicvoid setIndexes(int[] indexes){ ;U<;R
this.indexes = indexes; Q}d6+ C
} $Lv,e\]
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publicint getStartIndex(){ >K1)XP
return startIndex; RmY5/IYR|:
} _,"T;i
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publicvoid setStartIndex(int startIndex){ <w`
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if(totalCount <= 0) Dz:A.x@$*
this.startIndex = 0; 21bvSK
elseif(startIndex >= totalCount) aB0L]i
this.startIndex = indexes f)l:^/WP+
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[indexes.length - 1]; Q4Zuz)r*
elseif(startIndex < 0) "6 |j
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this.startIndex = 0; d
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else{ *%7 [{Loz
this.startIndex = indexes tisSj ?+
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[startIndex / pageSize]; XxcY
} m.pB]yq&
} jB!p,fqcb
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publicint getNextIndex(){ ~ P"@^cq
int nextIndex = getStartIndex() + 6O
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pageSize; ;e415T
if(nextIndex >= totalCount) 9+nB;vA
return getStartIndex(); Ci4`,
else m~'!
return nextIndex; Yrs7F.Y"
} aY}:9qBice
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publicint getPreviousIndex(){ @X+m,u
int previousIndex = getStartIndex() - %OB:lAeJ
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pageSize; d00#;R
if(previousIndex < 0) uf]SPG#/D
return0; <k!M+}a 9V
else #<s6L"Z-
return previousIndex; 3_|<CE6
} W@`2+}
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} >h1 3i@`r
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抽象业务类 !TvNT}4 Z
java代码: FM;NA{
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/** (-Cxv`7
* Created on 2005-7-12 nNz1gV:0X
*/
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package com.javaeye.common.business; {L~j;p_G&
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import java.io.Serializable; 7rQwn2XD{
import java.util.List; Swz{5 J2C
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import org.hibernate.Criteria; |a4cER.'2^
import org.hibernate.HibernateException; a?jUm.
import org.hibernate.Session; |0ATH`{
import org.hibernate.criterion.DetachedCriteria; 6D|[3rXr
import org.hibernate.criterion.Projections; pMB!I9q
import L#O1>
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org.springframework.orm.hibernate3.HibernateCallback; LvtHWt
import U{i xok
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org.springframework.orm.hibernate3.support.HibernateDaoS E! d?@Xr@
q\s"B.(G"
upport; 2 j.6
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import com.javaeye.common.util.PaginationSupport; X-LCIT|1
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public abstract class AbstractManager extends |y9(qcKn$
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HibernateDaoSupport { zU7co.G
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privateboolean cacheQueries = false; _D~l2M
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privateString queryCacheRegion; "Vh3hnS~
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publicvoid setCacheQueries(boolean $mxm?7ZVR
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cacheQueries){ }`KK
this.cacheQueries = cacheQueries; 5~D(jHY;
} ebno:)
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publicvoid setQueryCacheRegion(String ;)~}/nR<a
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queryCacheRegion){ 8tfM,.]_i
this.queryCacheRegion = &O
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queryCacheRegion; n(I,pF
} $7h]A$$Fv
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publicvoid save(finalObject entity){ Q^\m@7O
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getHibernateTemplate().save(entity); _%g L
} :o~]FVf
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publicvoid persist(finalObject entity){ E{;F4wT_@
getHibernateTemplate().save(entity); Z8C~o)n9
} e"oTlB
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publicvoid update(finalObject entity){ %xt;&HE
getHibernateTemplate().update(entity); Q,nJz*AJ
} UQZl:DYa
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publicvoid delete(finalObject entity){ "@z X{^:
getHibernateTemplate().delete(entity); ^H"o=K8=
} &F-
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publicObject load(finalClass entity, y1{TVpN
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finalSerializable id){ KH$|wv
return getHibernateTemplate().load IG+g7kDCY
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(entity, id); k5M5bH',
} IOA2/WQu
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publicObject get(finalClass entity, |kY}G3/
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finalSerializable id){ 7|5X> yt
return getHibernateTemplate().get Ii9[[I
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(entity, id); <%o9*)F
} dGyrzuPJ
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publicList findAll(finalClass entity){ arIEd VfNa
return getHibernateTemplate().find("from Um}f7^fp^l
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" + entity.getName()); 3Ccy %;
} 7}:+Yx
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publicList findByNamedQuery(finalString Brtsig,4
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namedQuery){ NnH]c+
return getHibernateTemplate NSa6\.W)
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().findByNamedQuery(namedQuery); T;G<62`.h
} {xAd>fGG+y
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publicList findByNamedQuery(finalString query, y\omJx=,
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finalObject parameter){ oXjoQ
return getHibernateTemplate 9X?RJ."J
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().findByNamedQuery(query, parameter); @XJ#oxM^
} ?K+q~DzNSD
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publicList findByNamedQuery(finalString query, ;j.-6#n
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finalObject[] parameters){ cYp/? \
return getHibernateTemplate zauDwV=
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().findByNamedQuery(query, parameters); fy]c=:EmD
} UX+vU@Co[
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publicList find(finalString query){ `OfD^Q=
return getHibernateTemplate().find SJ91(K
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(query); ua"2nVxK_K
} /GVjesN
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publicList find(finalString query, finalObject LSo*JO6
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parameter){ nK32or3
return getHibernateTemplate().find )X;051Q
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(query, parameter); J5(0J7C
} 06O_!"GD}
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public PaginationSupport findPageByCriteria \-pqqSy
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(final DetachedCriteria detachedCriteria){ (i L*1f
return findPageByCriteria 8v z h5,U
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); J/fnSy
} @I}VD\pF
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public PaginationSupport findPageByCriteria .%y'q!?
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(final DetachedCriteria detachedCriteria, finalint 41R6V>e@9J
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startIndex){ HCsd$M;Hbv
return findPageByCriteria 5x%Blkx
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(detachedCriteria, PaginationSupport.PAGESIZE, K-~g IlbQ`
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startIndex); 7nNNc[d*=
} e
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public PaginationSupport findPageByCriteria F)KR8(
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(final DetachedCriteria detachedCriteria, finalint (BFwE@1"
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pageSize, tu Y+n2
finalint startIndex){ }% f7O
return(PaginationSupport) VP>*J`'H
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getHibernateTemplate().execute(new HibernateCallback(){ a_+?#m
publicObject doInHibernate ]+46r!r|
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(Session session)throws HibernateException { 9@ YKx0
Criteria criteria = zBlv?JwG
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detachedCriteria.getExecutableCriteria(session); 6F!B*lr
int totalCount = (M"rpG>L
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((Integer) criteria.setProjection(Projections.rowCount 2mnAL#
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()).uniqueResult()).intValue(); e*qGrg (E
criteria.setProjection E(j#R"
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(null); t))MZw&@
List items = ;:j1FOj
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criteria.setFirstResult(startIndex).setMaxResults hO&b\#@~
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(pageSize).list(); GLyPgZ`|
PaginationSupport ps = :^WF%X
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new PaginationSupport(items, totalCount, pageSize, 71\53Qr#U
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startIndex); njf\fw_
return ps; C<AW)|r_
} ;RJ
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}, true); ?*yyne
} n
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public List findAllByCriteria(final V0v,s^\H
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DetachedCriteria detachedCriteria){ BH1h2OEe#
return(List) getHibernateTemplate w^ut,`yWR
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().execute(new HibernateCallback(){ ?T2>juf]5~
publicObject doInHibernate dgF%&*Il]O
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(Session session)throws HibernateException { E I zy
Criteria criteria = UPU$SZAIx
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detachedCriteria.getExecutableCriteria(session); ]vlBYAW'
return criteria.list(); jZzTnmm&?
} 1'\QD`M9^
}, true); X0u,QSt'O
} q50F!yHC-
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public int getCountByCriteria(final z'"7zLQ
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DetachedCriteria detachedCriteria){ 4lB??`UN
Integer count = (Integer) /W$i8g
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getHibernateTemplate().execute(new HibernateCallback(){ -p&u=
publicObject doInHibernate <mE`<-$
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(Session session)throws HibernateException { Zt!A!Afu
Criteria criteria = Os@b8V 8,A
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detachedCriteria.getExecutableCriteria(session); nf/?7~3?[
return b/'c
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criteria.setProjection(Projections.rowCount X+aQ 7^"s
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()).uniqueResult(); C~B ]@xxK)
} ^;RK-)
}, true); [|OII!"
return count.intValue(); P[WkW#
} Gv&G2^
} w!7ApEH1
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用户在web层构造查询条件detachedCriteria,和可选的 0cq@lT6
.how@>:P+
startIndex,调用业务bean的相应findByCriteria方法,返回一个 93HVx#
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PaginationSupport的实例ps。 i=aR~
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ps.getItems()得到已分页好的结果集 &/? Ct!_
ps.getIndexes()得到分页索引的数组 l~rj7f;
ps.getTotalCount()得到总结果数 }_]AQN$'G
ps.getStartIndex()当前分页索引 e{5?+6KH
ps.getNextIndex()下一页索引 Or5?Gt
ps.getPreviousIndex()上一页索引 [j+:2@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =0=#M(w
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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 iYStl
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: z%YNZ^d
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首先,为了实现分页查询,我封装了一个Page类: ,x8;| o5
java代码: I9S;t_Z<
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/*Created on 2005-4-14*/ JXK\mah
package org.flyware.util.page; #{8IFA
i)o;,~ee
/** EL?(D
* @author Joa 'QCIKCn<
* Tn}`VW~
*/ 6h;(b2p{
publicclass Page { 8)X9abC
c* {6T}VZr
/** imply if the page has previous page */ r(>S
privateboolean hasPrePage; %bDxvaftT
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/** imply if the page has next page */ (F4e}hr&
privateboolean hasNextPage; xnY?<?J"!
$Z@*!B^
/** the number of every page */ ?G,4N<]Nu
privateint everyPage; >!=@TK(~
c@t?R$c
/** the total page number */ ^c\O,*:
privateint totalPage; $+*nb4
|Kd#pYt%O
/** the number of current page */ f$o^Xu
privateint currentPage; Sa= tiOv
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/** the begin index of the records by the current rwF$aR>9
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query */ c{=Sy;i@
privateint beginIndex; $o[-xNn1
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&h334N|4{
/** The default constructor */ KZppQ0
public Page(){ ?"x4u#x
(9]Uuvfp6"
} "\b>JV5
RQ,#TbAe
/** construct the page by everyPage :;+!ID_
* @param everyPage *G58t`]r
* */ f7=MgFi
public Page(int everyPage){ o<Zlm)"%1
this.everyPage = everyPage; |
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} 3V k8'
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/** The whole constructor */ hd)Jq'MCS
public Page(boolean hasPrePage, boolean hasNextPage, L/8oqO|
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int everyPage, int totalPage, TA[%eMvA
int currentPage, int beginIndex){ WX&IQ@
this.hasPrePage = hasPrePage; T~[:oil
this.hasNextPage = hasNextPage; hFIh<m=C?Y
this.everyPage = everyPage; cbJgeif
this.totalPage = totalPage; `|'w]rj:"+
this.currentPage = currentPage; `nPdZ.
this.beginIndex = beginIndex; C`.YOkpj
} nrl?<4_
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/** N*Aw-\Bk
* @return N<)CG,/w[M
* Returns the beginIndex. 4=yzf
*/ .|,LBc!
publicint getBeginIndex(){ >tM4|w|
return beginIndex; @;/Pl>$|'G
} ?H=YJK$k
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/** P#O"{+`
* @param beginIndex A!lZyG!3
* The beginIndex to set. K.
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*/ t#NPbLZ
publicvoid setBeginIndex(int beginIndex){ WyO*8b_
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this.beginIndex = beginIndex; (!}N&!t
} G+
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/** xs"i_se
* @return h"`\'(,X
* Returns the currentPage. J6Ilg@}\
*/
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publicint getCurrentPage(){ 2/?Zp=|j\
return currentPage; C[^VM$
} lJK]S=cd
#HcQ*BiF3
/** ,P~e)<.
* @param currentPage J}V4.R5d
* The currentPage to set. aq?bI:>8
*/ scV%p&{a
publicvoid setCurrentPage(int currentPage){ AwJg/VBo)
this.currentPage = currentPage; xQFRM aQE
} 5 {! fa
r^ ,_m,s'<
/** b<u\THy#
* @return eb_.@.a
* Returns the everyPage. Thggas,
*/ /uw@o9`~2-
publicint getEveryPage(){ j7P49{
return everyPage; ~^F]t$rz
} yX
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/** a
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* @param everyPage } 9@rhW
* The everyPage to set. ^%\a,~
*/ kepuh%KY[
publicvoid setEveryPage(int everyPage){ ().C
this.everyPage = everyPage; #/qcp|m
} iA[T'+.Y
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/** Y9abRrK
* @return +R~]5Rxd
* Returns the hasNextPage. e@hPb$7
*/ :DH@zR
publicboolean getHasNextPage(){ `gl?y;xC
return hasNextPage; yCjc5d|tT
} e#}t
am
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/** d!I%AlV
* @param hasNextPage `q}D#0
* The hasNextPage to set. LW=qX%o{
*/ SqAz((
publicvoid setHasNextPage(boolean hasNextPage){ nDkG}JkB!
this.hasNextPage = hasNextPage; (Q{JI~P
} 5 H._Q
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/** I gJu/{:y^
* @return o#FctM'Z
* Returns the hasPrePage. |]kiH^Ap
*/ W8<QgpV*
publicboolean getHasPrePage(){ ,.Gp_BI
return hasPrePage; ir^d7CV,
} SrA6}kS
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/** |1wZ`wGZ:L
* @param hasPrePage ],c0nz^%BR
* The hasPrePage to set. Kj0)/Fjl+
*/ % 3#g-
publicvoid setHasPrePage(boolean hasPrePage){ v=^^Mr"Z^
this.hasPrePage = hasPrePage; VmQ^F|
{
} rbf5~sw&8+
mpYBMSLM
/** L'y0$
* @return Returns the totalPage. " lD -*e4
* zZ}.2He8
*/ Wi$?k{C
publicint getTotalPage(){ )F9IzR-&m
return totalPage; Qe~C}j%
} #|\|G3Si
%
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/** {Lju7'5L
* @param totalPage 3\2&?VAjR
* The totalPage to set. >(:3H+
*/ z{R
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publicvoid setTotalPage(int totalPage){ ejg!1*H@n
this.totalPage = totalPage; J#d,?
} .UxkTads
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} e\z,^
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wgSFL6Ei
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 T#E{d
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个PageUtil,负责对Page对象进行构造: mcwd2)
java代码: qRT5|\l
# l1*# Z
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/*Created on 2005-4-14*/ qLBQ!>lR
package org.flyware.util.page; 8Ogg(uS70'
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import org.apache.commons.logging.Log; kU:Q&[/jzH
import org.apache.commons.logging.LogFactory; jhT/}"v
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/** #~Kno@
* @author Joa j\#)'>"
* Jn(|.eT|
*/ O-AC$C[d
publicclass PageUtil { aeMj4|{\
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privatestaticfinal Log logger = LogFactory.getLog Njo.-k
L `2{H%J`
(PageUtil.class); dsEvpa$?
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/** 9Eh*r@>
* Use the origin page to create a new page r 8N<<^
* @param page |$8N*7UD
* @param totalRecords "+Ks#
* @return M!G/5:VZ
*/ *"|f!t
publicstatic Page createPage(Page page, int Z'AjeZyyE
"<oR.f=0
totalRecords){ }lk9|U#6*`
return createPage(page.getEveryPage(), TPJuS)TU9
uxW |&q
page.getCurrentPage(), totalRecords); $y)tcVc
} %PVu>^
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/** rl"yE=
* the basic page utils not including exception 2Z(?pJyDM
$SLyI$<gP
handler E]Cm#B
* @param everyPage m=`V
* @param currentPage PtjAu
* @param totalRecords ubl
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* @return page j%!xb><
*/ IFSIQ
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publicstatic Page createPage(int everyPage, int 7vqE@;:dt
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currentPage, int totalRecords){ Dmtsu2o
everyPage = getEveryPage(everyPage); %)}_OXWf:
currentPage = getCurrentPage(currentPage); ZA4sEVHW
int beginIndex = getBeginIndex(everyPage, ^]LWcJ?"^!
S{cK~sZj
currentPage); 'pAq;2AA
int totalPage = getTotalPage(everyPage, Ud-c+, xX
B)DtJf
totalRecords); ]:6IW:
boolean hasNextPage = hasNextPage(currentPage, Kt#X'!9/<
,=6;dT
totalPage); neWx-O
boolean hasPrePage = hasPrePage(currentPage); Dk~
JH9#
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returnnew Page(hasPrePage, hasNextPage, )q7!CG'oY
everyPage, totalPage, f+Bv8 g
currentPage, N[=R$1\Z
uCFpH5>
beginIndex); 'kCr1t
} *xKY>E+
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privatestaticint getEveryPage(int everyPage){ (Sj?BZjC
return everyPage == 0 ? 10 : everyPage; Jpe\
} XQ k,xQ
0Q/BTT%X
privatestaticint getCurrentPage(int currentPage){ |>p?Cm
return currentPage == 0 ? 1 : currentPage; &W y9%
} ~EhM"go
_`]YWvh
privatestaticint getBeginIndex(int everyPage, int z!9w Lo^r
_K>YB>W}7
currentPage){ pu+jw<7
return(currentPage - 1) * everyPage; _AVP1
} 9r,7>#IF
/`B:F5r
privatestaticint getTotalPage(int everyPage, int GA)t!Xg^
l:VcV
totalRecords){ 7NfA)$
int totalPage = 0; 8DJoQl9
Z:%~Al:
if(totalRecords % everyPage == 0) czp}-{4X
totalPage = totalRecords / everyPage; (ft$ R?
else w>gB&59r
totalPage = totalRecords / everyPage + 1 ; )KD*G;<O]L
q vGkTE
return totalPage; QPpC_pZh
} L(qQ,1VY
(E?X@d iu
privatestaticboolean hasPrePage(int currentPage){ ^NiS7 )FX
return currentPage == 1 ? false : true; gflu!C6
} PPSSar
s8 0$
privatestaticboolean hasNextPage(int currentPage, YeCS`IXm
?Q%X,!~\:
int totalPage){ >hmBV7nR
return currentPage == totalPage || totalPage == T4x%dg
z#elwL6
0 ? false : true; -}9a%
} =5m~rJ<{
+&h<:/ V
j LG
Q^v"
} VsM~$
)
z8\z`#g!
U0X? ~ 1
fC$(l@O?
^9*kZV<K
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。 $@(+"
$
%d#h<e|,.
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 Dq G m
CDU$Gi
做法如下: B78e*nNS#2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 j!<(`
rsgTd\b
的信息,和一个结果集List: zLda+
java代码: aBonq]W
nkn4VA?"
!m<v@SmL\
/*Created on 2005-6-13*/ Oq3]ZUVa
package com.adt.bo; R
*uwp'@
7)#8p@Q
import java.util.List; +1o4l i
U+FI^Xrt#
import org.flyware.util.page.Page; BL^\"Xh$|
e;G}T%W
/** g ONybz6]
* @author Joa >j$y@"+
*/ O4.`N?Xq
publicclass Result { \]=''C=J
kt;uB
X3
private Page page; 9O2??N7f
8.m9 =+)8
private List content; 6I!B>V#U+
+l) [A{
/** n/Fx2QC{
* The default constructor @&xWd{8'
*/ Hru~Y}V
public Result(){ V|W[>/
super(); ziTE*rNJ
} x=%wPVJ
r&_bk
Y%
/** f~?4
* The constructor using fields 0 F-db
* xjK@Q1MJ
* @param page P4{!/&/
* @param content .TpM3b#r
*/ '74*-yd
public Result(Page page, List content){ p%ZOLoc)Y
this.page = page; Lh
rU fy
this.content = content; GMW,+
} :F`-<x/
h=
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/** R.P|gk
* @return Returns the content. *pj^d><
*/ `*-rz<G
publicList getContent(){ >1S39n5z.
return content; U]}f]GK
} >#[,OU} N
N SkIzaNY
/** uG,*m'x']
* @return Returns the page. |kK_B
:K
*/ 26B+qXEt
public Page getPage(){ 94Q?)0W$
return page; q)Qg'l^f
} *wp>a?sG\
_Y _v&
/** q>f|1Pf
* @param content fq4[/%6,O
* The content to set. h;DLD8L
*/ w
tSX(LNY
public void setContent(List content){ n=qu?xu
this.content = content; |!hN!j*)
}
+
C'<*
Lm1
-
/** !cNw8"SIU
* @param page 1)v]<Ga~%1
* The page to set. B
x-"<^<
*/ W!B\VB
publicvoid setPage(Page page){ w
21g&
this.page = page; CX3yIe~u
} :J;&Z{
} kG>m(n
wrm
ReT?
/ei(Q'pc[
6x iCTs0@
@ebSM#F?
2. 编写业务逻辑接口,并实现它(UserManager, qW
2'?B3<
/7LAd_P6
UserManagerImpl) e]zd6{g[m
java代码: ~ya@ YP]';
EK2mJCC|
Aq;WQyZ2
/*Created on 2005-7-15*/ lcfX(~/m^
package com.adt.service; sg%Ptp
t~_bquGk
import net.sf.hibernate.HibernateException; 9^g?/8
J. $U_k
import org.flyware.util.page.Page; 2F#DJN#
1
.Nfl@]
import com.adt.bo.Result; >SHP,><H/
\V%l.P4>e
/** pKkBAr,
* @author Joa
[yx8?5
*/ pE381Cw
publicinterface UserManager { GZzBATx
sh)[|?7z
public Result listUser(Page page)throws k] iyx
^,{ r[}
HibernateException; 3A!Qu$r9
TrR=3_;.7
} cm17hPe`}n
dM)x|b3z
;5&=I|xqe
S+7u,%n/
/Y0oA3am
java代码: @TvDxY1)6Z
i%n9RuULh
|31/*J!@z*
/*Created on 2005-7-15*/ W0k7(v)
package com.adt.service.impl; m8<.TCIQ
%`\=qSf*
import java.util.List; Wa<SYJ
Lk2;\ D>
import net.sf.hibernate.HibernateException; QC<O=<$Q[
C Xh>'K
import org.flyware.util.page.Page; w`X0^<Fv
import org.flyware.util.page.PageUtil; -9;XNp
bBY7^k
import com.adt.bo.Result; Aa}Nr5{O|
import com.adt.dao.UserDAO; k]=lo'bF4
import com.adt.exception.ObjectNotFoundException; =^mBj?(V7
import com.adt.service.UserManager; :!L>_ f
j^m x ,
/** N?v}\ PU
* @author Joa MnTqWC90
*/
;(
[^+_/
publicclass UserManagerImpl implements UserManager { a[ yyEgm2
y`a]##1j$M
private UserDAO userDAO; mGh8/Xt
mWTV)z57
/** dmPAPCm%y
* @param userDAO The userDAO to set. s|D[_N!|
*/ \pVNJy$`<
publicvoid setUserDAO(UserDAO userDAO){ f0 "_ {\
this.userDAO = userDAO; K;*B$2Z#k
}
[7Liken
go?}M]c%7
/* (non-Javadoc) NeR1}W
* @see com.adt.service.UserManager#listUser "L+NN|
J[al4e^
(org.flyware.util.page.Page) #L+ZHs~
*/ "{x+ \Z\
public Result listUser(Page page)throws @*=eqO
(05a9
HibernateException, ObjectNotFoundException { mbXW$E-&R2
int totalRecords = userDAO.getUserCount(); ?U3~rro!
if(totalRecords == 0)
]iry'eljy
throw new ObjectNotFoundException e]@
B61lc
>!PCEw<i
("userNotExist"); p%-;hL!
page = PageUtil.createPage(page, totalRecords); .o)
List users = userDAO.getUserByPage(page); Sz-TarTF
returnnew Result(page, users); jqQG n"!
} oT i$@q
FJ2~SKWT
} ^?S lM
thSXri?kl
V|)nUsU
Y2W{?<99
u-R;rf5%k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1AQ3<
~\u~>mtchu
询,接下来编写UserDAO的代码: " nLWvV1
3. UserDAO 和 UserDAOImpl: SI/3Dz[
java代码: E=]$nE]b
Dop,_94G
WDF6.i ?
/*Created on 2005-7-15*/ ]F
srk
package com.adt.dao; Q*8efzgs|
Ws:+P~8
import java.util.List; z6Zd/mt~x
P\&n0C~
import org.flyware.util.page.Page; >:|jds#
7~H"m/;U&
import net.sf.hibernate.HibernateException; ne# %Gr
+HEL ^
/** ,'byJlw_pv
* @author Joa zcOG[-
*/ q OV$4[r
publicinterface UserDAO extends BaseDAO { nG7E j#1
<x1,4a~
publicList getUserByName(String name)throws #YK=e&da
Rts.jm>[
HibernateException; p~z\&&0U0
naM=oSB(
publicint getUserCount()throws HibernateException; D<lV WP
:oytJhxU
publicList getUserByPage(Page page)throws =xr2-K)e
)JOo|pr-K
HibernateException; C,$7fW{?
xG|lmYt76
} wp<f{^ et
y<m}dW6[\
/J!~0~F
{4r } jH
TE-(Zil\
java代码: ;RS^^vDm
s:JQV
G& @_,y|
/*Created on 2005-7-15*/ +oiuulA
package com.adt.dao.impl; R]N"P:wf@
Lv@'v4.({
import java.util.List; {;3a^K
4YA1~7R
import org.flyware.util.page.Page; !-tVt
D
!=]cASPGD
import net.sf.hibernate.HibernateException; CJt(c,!z
import net.sf.hibernate.Query; 6JD~G\$
^]9.$$GU\A
import com.adt.dao.UserDAO; JPq' C$
"LM[WcDX
/** ,yTT,)@<
* @author Joa v(l:N@L
*/ "cGjHy\j`
public class UserDAOImpl extends BaseDAOHibernateImpl p5#UH
v dPb-z4
implements UserDAO { $|K-wN[
j=Z;M1
/* (non-Javadoc) J'*`K>wV
* @see com.adt.dao.UserDAO#getUserByName v4r%'bA
ms#|Yl1/|
(java.lang.String) i*e'eZ;)
*/ a>#]d
publicList getUserByName(String name)throws _^p\
u
"T.Qb/97@
HibernateException { @UW*o&pGqL
String querySentence = "FROM user in class (#rhD}
U?j[
8z
com.adt.po.User WHERE user.name=:name"; c
Sktm&SP
Query query = getSession().createQuery 5
&s<&h
*_eY +\j
(querySentence); [ N0"mE<
query.setParameter("name", name); (4IH%Ez){
return query.list(); A5,(P$@k
} s[}cj+0
;&
zBNj
/* (non-Javadoc) ?;DzWCL~9
* @see com.adt.dao.UserDAO#getUserCount() hz rS_v
*/ l:j>d^V*&x
publicint getUserCount()throws HibernateException { 14yzGhA
int count = 0; {$'oKJy*
String querySentence = "SELECT count(*) FROM dyt.(2
)pw53,7>aN
user in class com.adt.po.User"; ,Ofou8C6
Query query = getSession().createQuery !$#8Z".{v{
P.kf|,8L
(querySentence); `FAZAC\
count = ((Integer)query.iterate().next &W
N
R{
iM~qSRb#mJ
()).intValue(); #yOn /
return count; f&?
8fB8{
} S~V?Qe@&Z
Im@Yx^gc
/* (non-Javadoc) a4eE/1
* @see com.adt.dao.UserDAO#getUserByPage )
-@Dh6F
#g]eDU-[
(org.flyware.util.page.Page) hv )d
*/ wcW}Sv[r
publicList getUserByPage(Page page)throws ]
jycg@=B
vzZ"TSP
HibernateException { tTPjCl
String querySentence = "FROM user in class <4%PT2R
<Gz* 2i
com.adt.po.User"; +{cCKRm
Query query = getSession().createQuery V(OD^GU
s;xErH@RA
(querySentence); ^o Q^/v~
query.setFirstResult(page.getBeginIndex()) RT"JAJTi/
.setMaxResults(page.getEveryPage()); $#FA/+<&$
return query.list(); Cd7l+~*Y
} 1_z~<d
@?;
aV G4Df
} Y{2L[5_1
%
r0AhWv
Hf9F:yH
zJG=9C?
5>&C.+A 9
至此,一个完整的分页程序完成。前台的只需要调用 }c'T]h\S
zX&wfE8T
userManager.listUser(page)即可得到一个Page对象和结果集对象 8:jakOeT
1p(9hVA
的综合体,而传入的参数page对象则可以由前台传入,如果用 n@9R|biO
z`Xc] cPi
webwork,甚至可以直接在配置文件中指定。 _OJ19 Ry
0-8'.C1v
下面给出一个webwork调用示例: TFtD>q X
java代码: R^Y_i
|4F'Zu}g>
|/;X-+f8
/*Created on 2005-6-17*/ "PC9[i
package com.adt.action.user; k9iB-=X?4s
}Pj;9ivz
import java.util.List; &Tk@2<5=
@!%HEs!# #
import org.apache.commons.logging.Log; 7z3YzQ=Kg
import org.apache.commons.logging.LogFactory; C^ Oy.s
import org.flyware.util.page.Page; N@R?<a
90!67Ap`x
import com.adt.bo.Result; -{eI6#z|\A
import com.adt.service.UserService; lNB<_SO
import com.opensymphony.xwork.Action; .<.#g+
7DIFJJE'
/** `yrJ }f
* @author Joa ^zR*s |1Q
*/ S0tPnwco[~
publicclass ListUser implementsAction{ B q7Qbj
g UA_&_
privatestaticfinal Log logger = LogFactory.getLog [u7i)fn5?
AI2@VvB
(ListUser.class); Kl w9
-Ps kUl'
private UserService userService; Cm#[$T@C
=Y-mc#{8
private Page page; 1IWP~G
=yLJGNK[
privateList users; Ypw:Vp
jCL 1Bj
/* )"f*Mp
* (non-Javadoc) wQN/MYF[
* /t_AiM,(
* @see com.opensymphony.xwork.Action#execute() pFwhvw
*/ w>6cc#>q
publicString execute()throwsException{ q 1+{MPJ
Result result = userService.listUser(page); [,ZHn$\
page = result.getPage(); G*rlU
users = result.getContent(); 7kh(WtUz
return SUCCESS; 'klYGp
} br4 %(w(d
T7j,%ay9
/** H]VoXJ\*
* @return Returns the page. 0Y9fK? (
*/ +cC$4t0$^A
public Page getPage(){ P6u%-#
return page; rjL4t^rT
} |M(0CYO
6}GcMhU<r
/** utBKl'`
* @return Returns the users. @;h$!w<
*/ fb D
publicList getUsers(){ `8G {-_
return users; 9Vtn62+
} 6Wc'5t3
~a`
vk@8
/** 4>t=r\"4
* @param page HHg[6aw
* The page to set. ?7R&=B1g
*/ eTZ2f
publicvoid setPage(Page page){ {Zrf>ST
this.page = page; Gw?$.@L'I6
} e6uVUzP4
FlepM*
/** S~Yu;
* @param users 6:qh%ZR
* The users to set. U$ 22 r b
*/ tqicyNL
publicvoid setUsers(List users){ 7q'T,'[
this.users = users; 0M 5m8
} FmC
[u
\Ea(f**2B
/** T/TMi&:?.
* @param userService _A,mY6*
* The userService to set. {qL}:ha?
*/ ^6FU]
publicvoid setUserService(UserService userService){ l$3YJ.n|s~
this.userService = userService; *e
*V%w~75
} _q3|Ddm2LN
} SB=%(]S
*#Hw6N0#
zoHFTD4 g
t B Kra
U$^ $7g 3
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, =SLCG.
@t<KS&
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 uZ8^" W
f/{*v4!
么只需要: A,]%*kg2
java代码: 6tv-PgZ
ioJr2wq6
rxQ&N[r2
<?xml version="1.0"?> (?lKedA>2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork zb& 3{,
|7%#z~rT
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <-F[q'!C1
^>m"j6`h,
1.0.dtd"> QV9z81[
jRNDi_u?Wb
<xwork> )jHH-=JM
eD?f|bif
<package name="user" extends="webwork- &AhkP=Yw
zHk7!|%Y
interceptors"> TI}Y U
B):hm
<!-- The default interceptor stack name {`=k$1
D);w)`
--> J3,m{%EtNM
<default-interceptor-ref ]Ofs,U^
Pj{Y
name="myDefaultWebStack"/> 22FHD4
/L*JHNu"_
<action name="listUser" .l +yK-BZ
BSHtoD@e7
class="com.adt.action.user.ListUser"> [LDY;k~5+
<param nV3I6
L{Kl!
name="page.everyPage">10</param> x f<wM]&
<result C9L_`[9DO
!i5~>p|4@
name="success">/user/user_list.jsp</result> MyaJhA6c
</action> V3c7F4\
OS sYmF
</package> DZqY=Sze
O8)N`#1>+
</xwork> <Xl/U^B
qUKSo9
Q Zv}\C-c
/[+%<5s
^j]_MiA4
9s&Tv&%VN
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Q%n$IQr4gM
,WtJ&S7?
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。 tzrvIVD
V2LvE.Kj
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 }0idFotck
}) Zcw1g
zLybf:#
*I9O+/,
dq^vK
我写的一个用于分页的类,用了泛型了,hoho +a0` ,Jc
M3Oqto<8"
java代码: X}B]0z>
x4-_K%
~Aw.=Yi=
package com.intokr.util; OZ,Xu&N
6os{q`/Q])
import java.util.List; ($'5xPb
]-cSTtO
/** DIF-%X5
* 用于分页的类<br> +0g L!r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> tR(nD UHV5
* ~Xz?H=}U+
* @version 0.01 9nSfFGu
* @author cheng -_ <z_IL\%
*/ qylI/,y{
public class Paginator<E> { ip!-~HNwJ
privateint count = 0; // 总记录数 +F+M[ef<ws
privateint p = 1; // 页编号 ,-[z?dvO
privateint num = 20; // 每页的记录数 hGJANA
privateList<E> results = null; // 结果 %
Ou'+A
;Q,,i
/** VG|FjD
* 结果总数 @7K(_Wd
*/ pT/z`o$#V
publicint getCount(){ B}0!b7!
return count; :*Y2na)qQ
} sW@_' Lw
`G`yA%
publicvoid setCount(int count){ 1P?|.W_^1
this.count = count; iTVZo?lVo
} T{)_vQ
S? #6{rx
/** tE,&
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* 本结果所在的页码,从1开始 F}?4h Dt
* n
j2=}6
* @return Returns the pageNo. -ARks_\
*/ i!)\m0Wm
publicint getP(){ oI-,6G}
return p; ($-m}UF\/
} 2P ^x'I
iFnD`l6)
/** BhhFij4
* if(p<=0) p=1 xZA.<Yd^r
* 1Eb2X}XC
* @param p :l&Yq!5
*/ SG]Sx4fg,Y
publicvoid setP(int p){ k$ b)
if(p <= 0)
6ZfL-E{
p = 1; Kr;;aT0P
this.p = p;
hLj7i?
} +QNsI2t;r
r1:CHIwK
/** j4I ~
* 每页记录数量 3OFI>x,h
*/ bEln.)
publicint getNum(){ o59b#9
return num; 54=*vokX_
} }(7TiCwd
\440gH`
/** h"nhDART<
* if(num<1) num=1 R3%%;` c=
*/ aYn5AP'PH
publicvoid setNum(int num){ k-^le|n9
if(num < 1) AEkjy h\
num = 1; Da8
|eN}
this.num = num; 4w)>}
} G.`},c;A-
b!bg sd
/** UE/JV_/S;
* 获得总页数 `aTw!QBfG
*/ PQp/&D4K
publicint getPageNum(){ 0TZB}c#qT
return(count - 1) / num + 1; sUU[QP-
} .N( X.C
Q[?R{w6
/** "By$!R-&
* 获得本页的开始编号,为 (p-1)*num+1 > l]Ble
*/ KWojMPs
publicint getStart(){ RLZfXXMn
return(p - 1) * num + 1; |<'6rJ[i>
} [>t;P,
U.X`z3q
/** `][vaLd`Q
* @return Returns the results. h,n}=g+?
*/ .+kg1=s
publicList<E> getResults(){ ` FOCX;
return results; 4XAs^>N+
} V0BT./ B\<
D|ra ;d
public void setResults(List<E> results){ (cyvE}g
this.results = results; 6l[v3l"t
} U!NuiKaQ26
zXD/hM
public String toString(){ h8X[*Wme
StringBuilder buff = new StringBuilder XwFTAaZ
bv VkN
(); b$yIM
buff.append("{"); -DK6(<:0
buff.append("count:").append(count); %P D}VF/Y
buff.append(",p:").append(p); e ^oGiL~
buff.append(",nump:").append(num); 9!FU,4 X
buff.append(",results:").append KJ:z\N8eo
yjsj+K
pL
(results); un4fnoc
buff.append("}"); {Wi*B(
return buff.toString(); 7'"qW"<
} ptrwZ8'
4wkv#vi7!-
} k1oJ<$Q
DP0@x+`k
_GFh+eS}