Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x%;Q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 [|sKu#yW
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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 D4"](RXH
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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 3xW;qNj:!l
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分页支持类: JuGQS24
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java代码: 4LU'E%vlC
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package com.javaeye.common.util; 7eh|5e$@
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import java.util.List; F:/R'0
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publicclass PaginationSupport { t[6 g9 e$
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publicfinalstaticint PAGESIZE = 30; i\S } aCm
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privateint pageSize = PAGESIZE; Av*R(d=`
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privateList items; O_f|R1G5z
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privateint totalCount; EX>|+zYL
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privateint[] indexes = newint[0]; 1Tn!.E *
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privateint startIndex = 0; %r5&CUE5?
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public PaginationSupport(List items, int O0xL;@rBe
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totalCount){ "F+
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setPageSize(PAGESIZE); *seKph+'c
setTotalCount(totalCount); vi6EI
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setItems(items); $ 8w
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setStartIndex(0); v&(X&q
} |xH"Xvp:
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public PaginationSupport(List items, int xIF
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totalCount, int startIndex){ OgrUP
setPageSize(PAGESIZE); t4?g_$>
setTotalCount(totalCount); I
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setItems(items); 9B'l+nP
setStartIndex(startIndex); ,ewg3mYHC&
} ;,'!
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public PaginationSupport(List items, int 3h";
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totalCount, int pageSize, int startIndex){ U:MkA(S%c
setPageSize(pageSize); 44?5]C7
setTotalCount(totalCount); #rV=!j||
setItems(items); ckt^D/c2
setStartIndex(startIndex); %>i7A?L
} ue/6DwUv
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publicList getItems(){ m[oe$yH
return items; Rv q_Zsm
} ER5Q` H
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publicvoid setItems(List items){ X>%2\S
this.items = items; 2{p`"xX
} ~A8lvuw3
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publicint getPageSize(){ >o 3X)
return pageSize; "MC&!AMv
} AXPUJ?V
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publicvoid setPageSize(int pageSize){ q9WdJ!-^X
this.pageSize = pageSize; kc8GnKM&mc
} >Fx$Rty
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publicint getTotalCount(){ OM!ES%c,
return totalCount; f`A
} z8Dn<h
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publicvoid setTotalCount(int totalCount){ `yYgL@Zt
if(totalCount > 0){ 4N$svA
this.totalCount = totalCount; P60 3P
int count = totalCount / W]2;5`MM
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pageSize; ;S?1E:\av
if(totalCount % pageSize > 0) Q^MB%L;D
count++; XZ|"7a s
indexes = newint[count]; niy@'
for(int i = 0; i < count; i++){ #(aROTV5a
indexes = pageSize * i+&="Z@
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} bq(*r:`"
}else{ BLaXp0
this.totalCount = 0; cWRB=`=qz
} lh#GD"^(w&
} ?sS'T7r
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publicint[] getIndexes(){ -|)[s[T~m
return indexes; =JVRm
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} )D[xY0Y~
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publicvoid setIndexes(int[] indexes){ M;iaNL(
this.indexes = indexes; nr-mf]W&
} HqF8:z?v
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publicint getStartIndex(){ *(>$4$9n
return startIndex; \pzvoj7{
} w
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publicvoid setStartIndex(int startIndex){ GzB%vsv95
if(totalCount <= 0) teB{GR
this.startIndex = 0; X^.r@tT
elseif(startIndex >= totalCount) [ThzLk#m
this.startIndex = indexes 2(c#m*Q!b
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[indexes.length - 1]; D$mrnm4d
elseif(startIndex < 0) kW:!$MX!
this.startIndex = 0; yv:NH|,/y
else{ =[jBOx&
this.startIndex = indexes V3+%KkN
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[startIndex / pageSize]; *
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} cq=R
} nWl0R=
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publicint getNextIndex(){ (,TO|
int nextIndex = getStartIndex() + <n:?WP~U
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pageSize; /vV 0$vg
if(nextIndex >= totalCount) 'q-h
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return getStartIndex(); LtU+w*Gj
else .iS]aJJ
return nextIndex; T*ic?!
} @t^2/H
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publicint getPreviousIndex(){ POG5x
int previousIndex = getStartIndex() - 2~4C5@SxL
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pageSize; k^]~NP
if(previousIndex < 0) tp]|/cx4
return0; lt4UNJ3w
else #.='dSj
return previousIndex; \wCL)t.cX
} Mzd}9x$'J
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} pZjFpd|
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抽象业务类 TGLXvP&
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java代码: YH>n{o;-
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/** f,#xicSB*
* Created on 2005-7-12 ;1 fM L,8
*/ '$zFGq
}}
package com.javaeye.common.business; S!]}}fKEFm
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import java.io.Serializable; zyr6Tv61U
import java.util.List; 'nno)kQ"
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import org.hibernate.Criteria; D4|_?O3|m
import org.hibernate.HibernateException; "mf;k^sqS
import org.hibernate.Session; \);rOqh
import org.hibernate.criterion.DetachedCriteria; On^#x]
import org.hibernate.criterion.Projections; 1rEP)66N
import :]s] =q&]
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org.springframework.orm.hibernate3.HibernateCallback; p"@|2a
import nM`) `!/
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org.springframework.orm.hibernate3.support.HibernateDaoS D|o@(V
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upport; X3[!xMij
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import com.javaeye.common.util.PaginationSupport; 1 GdD
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public abstract class AbstractManager extends 5o/rV.I
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HibernateDaoSupport { l+6(|"md
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privateboolean cacheQueries = false; pQNFH)=nw
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privateString queryCacheRegion; 6{'6_4;Fv(
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publicvoid setCacheQueries(boolean ?=kswf
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cacheQueries){ `?x$J
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this.cacheQueries = cacheQueries; arZIe+KW
} } Kt?0
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publicvoid setQueryCacheRegion(String Bv8C_-lV/
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queryCacheRegion){ nY)Pxahm 7
this.queryCacheRegion = Ao T 7sy7
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queryCacheRegion; cqx1NWlY
} +`8)U 3u0
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publicvoid save(finalObject entity){ : qRT9n$
getHibernateTemplate().save(entity); &J$5+"/;X
} LltguNM$
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publicvoid persist(finalObject entity){ V%lGJ]ZEa
getHibernateTemplate().save(entity); P-[K*/bPw
} VU9P\|c@<
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publicvoid update(finalObject entity){ GDp p`'\
getHibernateTemplate().update(entity); .E#Sm?gK
} CDnz
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publicvoid delete(finalObject entity){ aa8Qslm
getHibernateTemplate().delete(entity); ,hLSRj{
} !"%sp6Wc
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publicObject load(finalClass entity, ;bZ*6-\!-
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finalSerializable id){ ?3TV:fx"X
return getHibernateTemplate().load x}'4^Cv
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(entity, id); Y>Hl0$:=
} vUe
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publicObject get(finalClass entity, D1 ~x
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finalSerializable id){ KTjlWxD
return getHibernateTemplate().get |qcFmy
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(entity, id);
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} cvE.r330|
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publicList findAll(finalClass entity){ 6\fMzm
return getHibernateTemplate().find("from aroVyUs3j
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" + entity.getName()); s%[GQQ-N
} =yX&p:-&
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publicList findByNamedQuery(finalString Y%:0|utQC
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namedQuery){ 4bev*[k
return getHibernateTemplate |W*@}D
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().findByNamedQuery(namedQuery); RefRoCD1
} r p
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publicList findByNamedQuery(finalString query, X";ZUp
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finalObject parameter){ Fiu!!M6
return getHibernateTemplate ~,*YmB=Z
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().findByNamedQuery(query, parameter);
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} W.`Xm(y
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publicList findByNamedQuery(finalString query, Va@6=U7c
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finalObject[] parameters){ /8>0;bX+
return getHibernateTemplate o4%Vt} K
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().findByNamedQuery(query, parameters); a WeBav}_
} }\f(qw
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publicList find(finalString query){ Q:kVCm/;
return getHibernateTemplate().find l{6` k<J(
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(query); aM{@1mBm
} w3=)S\
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publicList find(finalString query, finalObject f `y"
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parameter){ ZUXse1,
return getHibernateTemplate().find L$lo~7<]
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(query, parameter); t{Hh&HX
} @P_C%}(<
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public PaginationSupport findPageByCriteria eu}Fd@GO
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(final DetachedCriteria detachedCriteria){ x2C/L
return findPageByCriteria ik2-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); m<4s*q0\i
} HDF"]l;
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public PaginationSupport findPageByCriteria 8cK\myn.
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(final DetachedCriteria detachedCriteria, finalint >f\zCT%cf
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startIndex){ -`!_h[
return findPageByCriteria Vk-W8[W 7
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(detachedCriteria, PaginationSupport.PAGESIZE, Ap]4QqU
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startIndex); w"cM<Ewu
} :1aL9 fT
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public PaginationSupport findPageByCriteria v"u7~Dw#1
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(final DetachedCriteria detachedCriteria, finalint
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(8CCesy&
pageSize, T3PX gL)o
finalint startIndex){ uR#'lb`3
return(PaginationSupport) <S]KaDu^
})@tA<+
getHibernateTemplate().execute(new HibernateCallback(){ -a
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publicObject doInHibernate f.||PH
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(Session session)throws HibernateException { +0]'| t F>
Criteria criteria = tC&fAE:S
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detachedCriteria.getExecutableCriteria(session); .Y!;xB/
int totalCount = $^}[g9]1
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((Integer) criteria.setProjection(Projections.rowCount 'pan9PW
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()).uniqueResult()).intValue(); a3Y{lc#z}
criteria.setProjection ZA0i)(j*Mn
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(null); uie~' K\y
List items = Mx8Gu^FW.d
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criteria.setFirstResult(startIndex).setMaxResults %y iD~&
<EtUnj:qK8
(pageSize).list(); B&?fM~J
PaginationSupport ps = }2lO _i}L
*=Doe2(!C
new PaginationSupport(items, totalCount, pageSize, +UzXN$73
tM)Iir*U#
startIndex); {>@QJlE0
return ps; GuT6K}~|D
} pprejUR
}, true); T|ZF/&XP
} n@
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public List findAllByCriteria(final Jen%}\
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DetachedCriteria detachedCriteria){ QC{u|
return(List) getHibernateTemplate Q"%QQo}}
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().execute(new HibernateCallback(){ d<x1*a
publicObject doInHibernate Z`Ax pTl
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(Session session)throws HibernateException { OUzR@$
Criteria criteria = }taLk@T
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detachedCriteria.getExecutableCriteria(session); 1Dq<{;rWb
return criteria.list(); ,h^r:g
} +3;Ody"59
}, true); 9@ndi u[
} ~^&R#4J
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public int getCountByCriteria(final @RGDhwS47
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DetachedCriteria detachedCriteria){ q\Rq!7(
Integer count = (Integer) /kB|1gFj
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getHibernateTemplate().execute(new HibernateCallback(){ EyY],W1 Y
publicObject doInHibernate WULAty
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(Session session)throws HibernateException { '^iUx,,ZQ
Criteria criteria = {~N3D4n^
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detachedCriteria.getExecutableCriteria(session); *KJB>W%@uM
return 8[zb{PRu
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criteria.setProjection(Projections.rowCount sb^mLH] 3
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()).uniqueResult(); OQp, 3M{_
} +-BwQ{92[:
}, true); L0Y0&;y|R
return count.intValue(); Fi2xr<7"
} I [0!SIqY
} +C+<BzR~A.
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用户在web层构造查询条件detachedCriteria,和可选的 *k [J6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9b"MQ[B4#a
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PaginationSupport的实例ps。 _=EKXE)&}
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ps.getItems()得到已分页好的结果集 NHm]`R,
ps.getIndexes()得到分页索引的数组 Ez+Z[*C
ps.getTotalCount()得到总结果数 bsS:"/?>
ps.getStartIndex()当前分页索引 %m&@o~+
ps.getNextIndex()下一页索引 ZmEEj-*7s
ps.getPreviousIndex()上一页索引 t"vRc4mf
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错
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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 o-C#|t3hH
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一下代码重构了。 mGjN_
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我把原本我的做法也提供出来供大家讨论吧: 7zemr>sIh
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首先,为了实现分页查询,我封装了一个Page类: ?jx1R^
java代码: Jh&~ToF!
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/*Created on 2005-4-14*/ oczG|_
package org.flyware.util.page; tDg}Ys=4K>
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/** m908jI_So
* @author Joa kM8{Cw
* ' o_:^'c
*/ sEJC-$
publicclass Page { 7!WA)@6
q
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/** imply if the page has previous page */ [* ?Awf`
privateboolean hasPrePage; W2FD+ wt
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/** imply if the page has next page */ m,UGWR
privateboolean hasNextPage; VHJM*&5
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/** the number of every page */ G 0%6ch^%
privateint everyPage; VXLT^iX
l*\y
/** the total page number */ scLn=
privateint totalPage; Q/>{f0
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/** the number of current page */ Ms~{9?
privateint currentPage; /+Lfrt
Qham^
/** the begin index of the records by the current n!p<A.O7@
F
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query */ ?HF%(>M
privateint beginIndex; [W%$qZlP
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/** The default constructor */ ])xx<5Jt4
public Page(){ I!e} )Y
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} ]o cWt3|
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/** construct the page by everyPage Og,$ sH}`
* @param everyPage .pvi!NnL-
* */ Tyvtmx M
public Page(int everyPage){ DxUKUE
this.everyPage = everyPage; \,u_7y2 c
} Re P|UH
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/** The whole constructor */ #Q2Y&2`yGT
public Page(boolean hasPrePage, boolean hasNextPage, $STaQ28C
uc;8 K,[t
>}+/{(K"E|
int everyPage, int totalPage, zIh['^3.n
int currentPage, int beginIndex){ /YZr~|65
this.hasPrePage = hasPrePage; l
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this.hasNextPage = hasNextPage; ,%uo6%
this.everyPage = everyPage; zT!drq: x
this.totalPage = totalPage; ]H`1F1=
this.currentPage = currentPage; &*+'>UEe5
this.beginIndex = beginIndex; :A/d to
} z^'gx@YD*v
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/** .Y&)4+ckL
* @return <StN%2WQ1
* Returns the beginIndex. z6*X%6,8
*/ ,P;Pm68V
publicint getBeginIndex(){ r>o63Q:
return beginIndex; Mu+0<>
} \WxukYH
8fl`r~bqZ
/** <
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* @param beginIndex Xu%'Z".>:
* The beginIndex to set. <sBbT`
*/ jPUwSIP
publicvoid setBeginIndex(int beginIndex){ }H^+A77v
this.beginIndex = beginIndex; E=nIRG|g
} <J)]mh dm
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/** %nf6%@s
* @return 5>[u `
* Returns the currentPage. sB7#
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*/ 4y|BOVl
publicint getCurrentPage(){ Q+[n91ey**
return currentPage; ]n6#VTz*
} Fld=5B^}
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/** LRL,m_gt
* @param currentPage fp`;U_-&0
* The currentPage to set. {*G9|#[/@
*/ Ayxkv)%:@)
publicvoid setCurrentPage(int currentPage){ dYJ(!V&
this.currentPage = currentPage; b3=rG(0f
} H?yK~bGQ
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/** z&zP)>Pv
* @return :D~D U,e'
* Returns the everyPage. KcWN,!G
*/ rNXQf'*I
publicint getEveryPage(){ ua3~iQj-
return everyPage; Z^3rLCa
} t}r' k/[
; ZA~p
/** 'DP1,7
* @param everyPage _kef0K6
* The everyPage to set. ?:Uv[|S#>
*/ J,'M4O\S
publicvoid setEveryPage(int everyPage){ /:m->
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this.everyPage = everyPage; p|U?86t
} <? q?Mn
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/** -*1d!
* @return G#ZH.24Y
* Returns the hasNextPage. &*M!lxDN
*/ {'7B6
publicboolean getHasNextPage(){ I9|mG'
return hasNextPage; f\|w'
} o_izl\
i1 }:8Unxf
/** t%d Z-Ym
* @param hasNextPage LBw1g<&
* The hasNextPage to set. cN/6SGHK
*/ Wf+cDpK
publicvoid setHasNextPage(boolean hasNextPage){ .]8ZwAs=&
this.hasNextPage = hasNextPage; n1Yp1"2b[
} x]}^v#
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/** `+]Qz =}
* @return *3+4[WT0]a
* Returns the hasPrePage. R$R *'l
*/ Xr,1&"B&t
publicboolean getHasPrePage(){ =/@D8{pU
return hasPrePage; <$D`Z-6
} tH!]Z4}u
g@d*\ P)
/** LQ@"Xe]5
* @param hasPrePage hZ|z|!g0
* The hasPrePage to set. 1I%w?^sm_
*/ g_;\iqxL
publicvoid setHasPrePage(boolean hasPrePage){ j
*
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this.hasPrePage = hasPrePage; d-oMQGOklb
} iDpSj!x/_
ld[I}88$
/** z0d.J1VW
* @return Returns the totalPage. wo3d#=
* Na<pwC
*/ j`EXlc~
publicint getTotalPage(){ Sh/08+@+L:
return totalPage; oh4E7yN
} !Lu2
,V7nzhA2
/** Z3Og=XHR
* @param totalPage Lc}LGq!
* The totalPage to set. 4VHn \
*/ )~X2
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publicvoid setTotalPage(int totalPage){ y#`tgJ:
this.totalPage = totalPage; ~]sc^[
} @="Pn5<]C
|44Ploz2b
} aEB_#1
~$ c\JKH-
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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 ,Co|-DYf}
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个PageUtil,负责对Page对象进行构造: :'Vf
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java代码: {$oj.V 4
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0
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/*Created on 2005-4-14*/ ;[ZEDF5H
package org.flyware.util.page; juJklSD
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import org.apache.commons.logging.Log; "69s)~
import org.apache.commons.logging.LogFactory; I^.Om])
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/** poE0{HOU
* @author Joa sJKI!
* ZtNN<7
*/ PI {bmZ
publicclass PageUtil { 8]c2r%J
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privatestaticfinal Log logger = LogFactory.getLog KYm0@O>;
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(PageUtil.class); A`%k:@
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/** rI{; I DV
* Use the origin page to create a new page M-VX;/&FR
* @param page G[ PtkPSJ
* @param totalRecords sI=xl
* @return Fe*R
*/ q1x`Bj
publicstatic Page createPage(Page page, int aqZi:icFa
yZY \MB/
totalRecords){ ~ah~cwmpS
return createPage(page.getEveryPage(), 6q\bB
[>I<#_^~
page.getCurrentPage(), totalRecords); (XTG8W sN
} uo9B9"&
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/** n`_{9R
* the basic page utils not including exception b#%hY{$j
Z?q]bSIT
handler u{cW:
* @param everyPage {lzWrUGO
* @param currentPage 4i;{!sT
* @param totalRecords 2QcOR4_V
* @return page :`#d:.@]o@
*/ \!X8
publicstatic Page createPage(int everyPage, int d'gfQlDny
g}oi!f$|
currentPage, int totalRecords){ tKuwpT1Qc
everyPage = getEveryPage(everyPage); )AtD}HEv
currentPage = getCurrentPage(currentPage); oSKXt}sh
int beginIndex = getBeginIndex(everyPage, _yx>TE2e
(S5R!lpO
currentPage); D/gw .XYL
int totalPage = getTotalPage(everyPage,
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totalRecords); 3ZPWze6
boolean hasNextPage = hasNextPage(currentPage, 7aRi5
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totalPage); Y] _ruDIW
boolean hasPrePage = hasPrePage(currentPage); gs[uD5oo<
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returnnew Page(hasPrePage, hasNextPage, RLXL&
everyPage, totalPage, ;`4&Rm9n?
currentPage, M/'sl;
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beginIndex); UhWNl]Z
} :r,pqnH_
{]!mrAjD
privatestaticint getEveryPage(int everyPage){ YlQ=5u^+
return everyPage == 0 ? 10 : everyPage; ah&D%8E
} 9&2O9Nz6
^mDe08.
%b
privatestaticint getCurrentPage(int currentPage){ 4B1v4g8}
return currentPage == 0 ? 1 : currentPage; rU:`*b<
} y2dCEmhY
t9` .bx8
privatestaticint getBeginIndex(int everyPage, int (t
K||*u
%N6A+5H
currentPage){ z,
)6"/;
return(currentPage - 1) * everyPage; ^zmG0EH,
} }OR@~V{Gj
"Yv_B3p
privatestaticint getTotalPage(int everyPage, int iC32nY?
wu!59pL
totalRecords){ iN\4gQ!
int totalPage = 0; 4jMFr,
85$m[+md
if(totalRecords % everyPage == 0) #4%]o%.
totalPage = totalRecords / everyPage; |bHelD|
else _ QI\
totalPage = totalRecords / everyPage + 1 ; BLdvyVFx
}5[qo`M
return totalPage; +F` S>U
} 'Cfl*iNb
(!aNq(
privatestaticboolean hasPrePage(int currentPage){ Jb@V}Ul$
return currentPage == 1 ? false : true; %QGC8Tz
} ;O6;.5q&
B$ PP&/
privatestaticboolean hasNextPage(int currentPage, o Q2Fjj
F?*-4I-
int totalPage){ 0B/,/KX
return currentPage == totalPage || totalPage == *8Xh(`
Mj7
S(I{NL}=$
0 ? false : true; cWaSn7p !X
} YMcD|Kb p
9'giU r
<tNBxa$gS
} oy=js -
-t'jNR'
Gbr=+AT
5h-SCB>P
oXh#a8
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 BC#C9|n
2B[X,rL.pX
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 @[<><uTH
M*, -zGr
做法如下: m@2QnA[4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <I\/n<*
y<|7z99L
的信息,和一个结果集List: { ]{/t-=
java代码: Lv;^My
{_[N<U:QT&
^e _hLX\SW
/*Created on 2005-6-13*/ feDlH[$
package com.adt.bo; qZtzO2Mt
x.!V^HQSN
import java.util.List; P6-s0]-g
5oW!YJg
import org.flyware.util.page.Page; qFCOUl
*xxx:*6rk;
/** ?W?c1>
* @author Joa kW Ml
*/ :Uzm
publicclass Result { (l~AV9!m:
/tx]5`#@7]
private Page page; Eex~xiiV
J s@hLP`
private List content; _~l5u8{^ 6
rxvx
/** .Ni\\
* The default constructor kzQ+j8.,U
*/ +s,=lL
public Result(){ 45@ I *`
super(); <e=#F-DE
} DZ'P@f)]
Ha0M)0Anv
/** *SbMqASv4G
* The constructor using fields ,GbR!j@6
* ,F8 Yn5h
* @param page / |;RV"
* @param content D[[|")Fn
*/ <s31W3<v
public Result(Page page, List content){ z;,u}u}aI
this.page = page; WTQ\PANAaR
this.content = content; urs,34h
} pSH=%u>
8?#/o c
/** T\6dm/5
* @return Returns the content. -n~1C{<
*/ E1aHKjLQ
publicList getContent(){ *MFIV02[N
return content; oQ/E}Zk@
} (&Kk7<#`
T?CdZc.
/** MO]F1E?X
* @return Returns the page. }#RakV4
*/ `t>l:<@%
public Page getPage(){ X6w6%fzOH>
return page; \$~|ZwV{
} Wq D4YGN
T@H^BGs
/** !I{0 _b{
* @param content b4%??"&<Y
* The content to set. ;LKkbT
5
*/ 13$%,q)
public void setContent(List content){ ,B*EVN
this.content = content; i(rL|d+'
} a_^\=&?'
n:I,PS0H<
/** :".ARCg
* @param page r..iko]T
* The page to set. <[a=ceL]|
*/ '2A)}uR
publicvoid setPage(Page page){ > ym,{EHK
this.page = page; ihhDO mUto
} q<x/Hat)
} ;0]aq0_#(
G=s}12/Z"{
6fE7W>la
58}U^IW
:;%2BSgFU
2. 编写业务逻辑接口,并实现它(UserManager, y1jCg%'H
"=HA Y
UserManagerImpl) K(e$esLs-
java代码: =g7x'
kN
9R!atPz9
gMi0FO'
/*Created on 2005-7-15*/ NR$3%0 nC6
package com.adt.service; &@X<zWg
;>%r9pz ~
import net.sf.hibernate.HibernateException; \i>?q
RN1y^`
import org.flyware.util.page.Page; k&M;,e3v6
h]5(].
import com.adt.bo.Result; Ye%~I`@?
S3C]AhW;
/** >>4qJ%bL
* @author Joa %"i(K@
*/ C!O0xhs
publicinterface UserManager { ^x ]r`b
;HfmzY(
public Result listUser(Page page)throws i'<[DjMDlm
>%_ \;svZG
HibernateException; `{@8Vsmy:
~f2z]JLr:
} 3oj' ytxN
M/B_#yK
,C\i^>=
df8k7D;~e
u= *FI
java代码: nAAs{
1/B>XkCJ
@,j*wnR
/*Created on 2005-7-15*/ /obfw^
package com.adt.service.impl; G6Axs1a
4d4ZT?V[
import java.util.List; 5:[0z5Hww
F} yW/
import net.sf.hibernate.HibernateException; [-1^-bb
4/~E4"8
import org.flyware.util.page.Page; oN~&_*FE
import org.flyware.util.page.PageUtil; 'T;P;:!\
VOsRAn/N
import com.adt.bo.Result; >0y'Rgfe
import com.adt.dao.UserDAO; h]&GLb&<?
import com.adt.exception.ObjectNotFoundException; :wyno#8`-
import com.adt.service.UserManager; a#(?P.6
IZ-1c1
/** Jl8H|<g~/
* @author Joa dh\'<|\K
*/ S"QWB`W2
publicclass UserManagerImpl implements UserManager { oAVnK[EMq`
PcMD])Z{G
private UserDAO userDAO; ;W
)Y
OT
1Faf$J~7|
/** 9Q^r
O26+
* @param userDAO The userDAO to set. @Sn(lnlB
*/ ^$jb7HMObI
publicvoid setUserDAO(UserDAO userDAO){ a 7V-C
this.userDAO = userDAO; @l5"nBs<_:
} ,.8KN<A2]'
H [\o RId
/* (non-Javadoc) CI0C1/:@
* @see com.adt.service.UserManager#listUser 3AtGy'NTp
N7zft
(org.flyware.util.page.Page) hpX9[3
*/ X=&ET)8-Y
public Result listUser(Page page)throws ',@3>T**
FIhk@TKa
HibernateException, ObjectNotFoundException { 7hcYD!DS
int totalRecords = userDAO.getUserCount(); *I.f1lz%*
if(totalRecords == 0) 20 h, ^
throw new ObjectNotFoundException CAWNDl4
RWZSQ~
("userNotExist"); 1N-\j0au
page = PageUtil.createPage(page, totalRecords); ]y'>=a|T
List users = userDAO.getUserByPage(page); &i6mW8l
returnnew Result(page, users); 83\pZ1>)_
} OX!tsARC@
UKvW Jnz
} -<!NXm|kvz
:U%W%
$k%2J9O
'G4ICtHQ
\'D0'\:vz
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *Kgks 4
HyZqUbHa
询,接下来编写UserDAO的代码: WX?IYQ+
3. UserDAO 和 UserDAOImpl: *)T^ChD,
java代码: HCs?iJ
WPMSm<[
`?_Q5lp/s
/*Created on 2005-7-15*/ AJ`h9%B
package com.adt.dao;
xF'EiX ~
6ojo :-%Vf
import java.util.List; 0@iY:aF
cf20.F{<
import org.flyware.util.page.Page; k"iOB-@B+
_op}1
import net.sf.hibernate.HibernateException; X51:
~KX/
Ai
/** h2]P]@nW;W
* @author Joa { @{']Y
*/ agDM~= #F
publicinterface UserDAO extends BaseDAO {
:KP@RZm
L+i=VGm0
publicList getUserByName(String name)throws `0gyr(fES
L48_96
HibernateException; rcG"o\g@+
,Ah;A[%?~
publicint getUserCount()throws HibernateException; #gs`#6 ,'
=K[yT:
publicList getUserByPage(Page page)throws eJX9_6m-
)'cMYC
HibernateException; G}raA%
!PQ<04jA!
} %pL''R9VF
:{l_FY436
Jk
n>S#SZ
\V~eVf;~
hD!7Cl Q
java代码: *P=VFP
I-(zaqp@
bwMm#f
/*Created on 2005-7-15*/ ;$wVu|&
package com.adt.dao.impl; nMUw_7Y6
:OT0yA=U
import java.util.List; Y\8)OBZ
y?? XIsF
import org.flyware.util.page.Page; })Vi
;dgp+
import net.sf.hibernate.HibernateException; E]-/Zbvdv
import net.sf.hibernate.Query; Qe:seW
bK&+5t&
import com.adt.dao.UserDAO; Feq]U?
;[OH(!
/** cR<fJ[*
* @author Joa Qpc__dA\
*/ +iRh
public class UserDAOImpl extends BaseDAOHibernateImpl U$z-e/
UySZbmP48
implements UserDAO { 7ZWgf"1j
X\qNG]
/* (non-Javadoc) 8'io$6d=
* @see com.adt.dao.UserDAO#getUserByName k,+0u/I
JP[K;/
(java.lang.String) yl+gL?IES
*/ fJ!R6D
publicList getUserByName(String name)throws $B5aje}i
w%jII{@,
HibernateException { \\;jw[P0
String querySentence = "FROM user in class I:1C8*/
.|i.Cq8
com.adt.po.User WHERE user.name=:name"; S3Xl
Query query = getSession().createQuery ope^~+c~\
Z o(rTCZX
(querySentence); e8?jmN`2
query.setParameter("name", name); ?J>
return query.list(); 60?%<oJ oH
} dSV8q
,D
-k"/X8
/* (non-Javadoc) *#+An<iT ;
* @see com.adt.dao.UserDAO#getUserCount() p}U ~+:v
*/ T'Dv.h
publicint getUserCount()throws HibernateException { -;WGS o
int count = 0; G
mA<
g
String querySentence = "SELECT count(*) FROM vy:Z /1q
LsU9 .
user in class com.adt.po.User"; }a(dyr`S
Query query = getSession().createQuery z 1X` o
k!'a,R:
(querySentence); 8$Y9ORs4
count = ((Integer)query.iterate().next bq0zxg%
8XE7]&)];
()).intValue(); Y9XEP7
return count; oE]QF.n#
} j3E7zRm] \
8VXH+5's
/* (non-Javadoc) p9{mS7R9T
* @see com.adt.dao.UserDAO#getUserByPage O)r4?<Q
28d'7El$
(org.flyware.util.page.Page) =]0&i]z[.
*/ m^;f(IK5
publicList getUserByPage(Page page)throws t'k$&l}+
J<jy2@"tXo
HibernateException { smo~7;
String querySentence = "FROM user in class h>m"GpF
x
GC}==^1
com.adt.po.User"; draN0vf
Query query = getSession().createQuery a<bwzX|.
\z(gqkc 6
(querySentence); JY(WK@
query.setFirstResult(page.getBeginIndex()) .U]-j\
.setMaxResults(page.getEveryPage()); v):Or'$~M
return query.list(); H$UcF1k<
} C!bUI8x
z
/f;~X"!
} >tW#/\x{
P( 8OQL:
A^<jy=F&
Oxd]y1
@b2aNS<T
至此,一个完整的分页程序完成。前台的只需要调用 h(EhkCf
%n9aaoD
userManager.listUser(page)即可得到一个Page对象和结果集对象 c9h6C
zIAD9mQex
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;u)I\3`*!
A2Gevj?F$
webwork,甚至可以直接在配置文件中指定。 ;uP:"k
o&$A]ph8X
下面给出一个webwork调用示例: 1p=]hC
java代码: oXF.1f/h
f%}xO+.s
$qj2w"'
/*Created on 2005-6-17*/ pZy~1L
package com.adt.action.user; Er?&Y,o
1iF1GkLEq
import java.util.List; TOQP'/
/mzlH
import org.apache.commons.logging.Log; 3(80:@|
import org.apache.commons.logging.LogFactory; |&i<bqLw:
import org.flyware.util.page.Page; aQ@oH#
}@d @3
import com.adt.bo.Result; 13x p_j
import com.adt.service.UserService; /cP"h!P}~~
import com.opensymphony.xwork.Action; m ~$v;?i
3/eca
/** ey$&;1x#5
* @author Joa uoh7Sz5!^
*/ o?Oc7$+u
publicclass ListUser implementsAction{ nAlQ7'
%d9uTm;
privatestaticfinal Log logger = LogFactory.getLog Pa:|_IXA
4{|"7/PE1
(ListUser.class); SXP]%{@R/
Ab.(7GFK
private UserService userService; H0vfUF53l
~*];pV]A[
private Page page; 8zW2zkv2|#
FGBbO\</
privateList users; l9Q-iJ
gw<q.XL
/* 1T
n}
* (non-Javadoc)
_;\_l
* `C'H.g\>2Q
* @see com.opensymphony.xwork.Action#execute() ('+d.F[109
*/ +]{G@pn
publicString execute()throwsException{ R[]Mdt<
Result result = userService.listUser(page); )MT}+ai
page = result.getPage(); g2Z`zQA7
users = result.getContent(); Q\sK"~@3
return SUCCESS; ]\HvK CN}
} vo{--+{ky!
S~G]~gt
/** t\O16O7S
* @return Returns the page. 42ge3>
*/ -jmY)(\
public Page getPage(){ ~6md !o%i
return page; &_8947
} {R{=+2K!|k
?:eV%`7
/** SUK?z!f<i
* @return Returns the users. pEz_qy[#
*/ ,|/f`Pl
publicList getUsers(){ Q22 GIr
return users; j<e2d7oN
} sV*H`N')S
#,'kXj
/** )D%~`,#pQ
* @param page J]r^W)O
* The page to set. 7F.4Ga;
*/ &5!8F(7
publicvoid setPage(Page page){ %J-GKpo/S
this.page = page; o^wqFX(Y
} i,VMd
dqcL]e
/** |JsZJ9W+J
* @param users V0Hj8}l;M
* The users to set. 4Wp=y
*/ l;E(I_
i)
publicvoid setUsers(List users){ 9:lFo=
this.users = users; AQ^u
} 0<*<$U
tX~w{|k
/** EKN~H$.
* @param userService ]eV8b*d6
* The userService to set. %@Jsal'
*/ b#o|6HkW
publicvoid setUserService(UserService userService){ PZzMHK?hP
this.userService = userService; I(
Mm?9F
}
{K!)Ss
} !H\F2Vxs
IAyp 2
]I6 J7A[
Zb#u0Tq
BFt> 9x]T
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, EiaW1Cs
qcRs$-J
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 #p{4^
>.D4co>
么只需要: #rg6,.I)<
java代码: 2>59q$|
-ze J#B)C
CNx8]
_2
<?xml version="1.0"?> 23jwAsSo
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $Z>'Jp
Y|/ 8up
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5E
<kwi
o,wUc"CE
1.0.dtd"> q0\6F^;M
f<6lf7qzC
<xwork> L4l!96]a
d0 /#nz
<package name="user" extends="webwork- B|X!>Q<g
NZz 8j^
interceptors"> D3K8F@d
W(/h Vt
<!-- The default interceptor stack name k|f4Cf,
\.}c9*)
--> uvS)8-o&F
<default-interceptor-ref 7>*vI7O0l
"J3x_~,[4m
name="myDefaultWebStack"/> ]J]h#ZHx
lk80#( :Z
<action name="listUser" !Xw5<J3L-
uXl3k:_n
class="com.adt.action.user.ListUser"> eJ81-!)
<param '/%H3A#L
/2VJX@h
name="page.everyPage">10</param> Mrb)
<result caX<
n>
S$XSei_q
name="success">/user/user_list.jsp</result> dUdT7ixo
</action> *DhiN
J<lO=
+mg
</package> B#1;r-^P<
Fv`,3aNB
</xwork> `~q <N
Q=yg8CQ
C+&l<
fM&
B4 }bVjs
ZqO^f*F>h
'@P^0+B!(.
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 FHI ;)wn=
2^yU ~`#
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。 ,UE83j8D^
x'R`.
!g3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 lks!w/yCF
D^;Uq8NDKq
;i:d+!3XwC
y4fdq7i~}9
"g8M0[7e3
我写的一个用于分页的类,用了泛型了,hoho +^T@sa`[I
"C`Ub
java代码: ,$&&-p I]
GWip-wI
S|+o-[e8O
package com.intokr.util; FaJ &GOM,
.#pU=v#/[
import java.util.List; iOO)Q\
}JAG7L&{
/** N ZSSg2TX#
* 用于分页的类<br> Mf``_=K
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _:27]K:
* *~i
])4
* @version 0.01 Hj,A5#|=J
* @author cheng lHX72s|V
*/ W5MTD]J
public class Paginator<E> { $E.I84UfX
privateint count = 0; // 总记录数 pyvSwD5t
privateint p = 1; // 页编号 S{m%H{A!
privateint num = 20; // 每页的记录数 q'82qY
privateList<E> results = null; // 结果 -3Vx76Y
0lR5<^B
/** #;nYg?d=
* 结果总数 ^gnZ+`3
*/
M/K5#8Arj
publicint getCount(){ [ibu/W$
return count; |
%Vh`HT
} ,nm*q#R,0
ixD)VcD-f
publicvoid setCount(int count){ HA>OkA/
this.count = count; oILZgNe'
} y
h9*z3
@I!0-OjL
/** b1?'gn~
* 本结果所在的页码,从1开始 0:Ol7
* !Q0w\j h
* @return Returns the pageNo. A~t
j/yq9
*/ ,DkNLE
publicint getP(){ 65Yv4pNL
return p; ,nDaqQ-C!!
} a!AA]
E=!\z%4
/** NHZz _a=
* if(p<=0) p=1 g7W"
* '(|ofJe!
* @param p hx]?&zT@
*/ @2 fg~2M1
publicvoid setP(int p){ q5)O%l !
if(p <= 0) 0.k7oB;f(@
p = 1; kL"2=7m;
this.p = p; wD'SPk5S?
} o:Sa,
!DK
}?Ai87-{
/** 2a Q[zK
* 每页记录数量 a HR"n|7{
*/ k_nql8H
publicint getNum(){ 9m~p0 ILh
return num; <l E<f+
} e h?zNu2=
n]o<S+z
/** ZRU{[4
* if(num<1) num=1 QX'qyojxN
*/ lchPpm9
publicvoid setNum(int num){ ~%kkeh\j
if(num < 1) fHd#u%63K
num = 1; %2V? ,zY@
this.num = num; g&Vx:fOC
} z/@slT
<k'h:KB?`
/** Uf;^%*P4
* 获得总页数 K:#I
*/
&powy7rR
publicint getPageNum(){ dk4CpN
return(count - 1) / num + 1; "n5N[1bk
} 5(Q%XQV*P
#( 146
/** 4yA+h2
* 获得本页的开始编号,为 (p-1)*num+1 O) n~](sC\
*/ 8\A#CQ5b
publicint getStart(){ 84zSK)=Y
return(p - 1) * num + 1; -3Z,EaG^
} <
!C)x
O^duZ*b
/** w;:*P
* @return Returns the results. tpQ(g%
*/ ">,|V-H
publicList<E> getResults(){ ^7WN{0
return results; 9`X\6s
} #rQ2gx4
ZdWm:(nkU
public void setResults(List<E> results){ w4{<n/"
this.results = results; W/bQd)Jvk
} }?_?V&K|
i^Y+?Sx
public String toString(){ u?<%q!
StringBuilder buff = new StringBuilder :g=qz~2Xk
}I6veagK
(); )e=D(qd
buff.append("{"); 2,b(,3{`4:
buff.append("count:").append(count); U-(01-
buff.append(",p:").append(p); g63(E,;;J
buff.append(",nump:").append(num); a;qryUyG
buff.append(",results:").append B:S>wFE(.
qUW!
G&R
(results); }"P|`"WW
buff.append("}"); &P}_bx
return buff.toString(); H0gbSd+
} li'YDtMKCY
?*1uN=oI{*
} c&?m>2^6
l<LP&
G kl71VX