Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "/Y<G
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 L<bYRGz
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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 8$\Za,)g
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 X6Un;UL
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分页支持类: ]53O}sH>
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java代码: ;xfO16fNk
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package com.javaeye.common.util; 0Y7$d`
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import java.util.List; S"zk!2@C
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publicclass PaginationSupport { 88
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publicfinalstaticint PAGESIZE = 30; XlVc\?
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privateint pageSize = PAGESIZE; cA<<&C
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privateList items; %4,xx'`
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privateint totalCount; _lXt8}:+
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privateint[] indexes = newint[0]; 8"x9#kyU<3
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privateint startIndex = 0; bw9
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public PaginationSupport(List items, int E tx`K5Tr]
,HZYG4,
totalCount){ )B ;M
setPageSize(PAGESIZE); T^]7R4Fg
setTotalCount(totalCount); 09d9S`cS\
setItems(items); b,Ke>.m
setStartIndex(0); ?eV_ACpZ8
} +< yhcSSTB
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public PaginationSupport(List items, int GF'f[F6oI
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totalCount, int startIndex){ hU"F;4p
setPageSize(PAGESIZE); ($62o&I
setTotalCount(totalCount); RDJ+QOVKg
setItems(items); F+ukAT
setStartIndex(startIndex); :3^dF}>
} |gv{z"
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public PaginationSupport(List items, int >F[GVmC
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totalCount, int pageSize, int startIndex){ 2n)gpLIJ
setPageSize(pageSize); BSgTde|3y
setTotalCount(totalCount); 3+(z_!Qh
setItems(items); b+{r!D}~
setStartIndex(startIndex); `\N]wlB2/b
} uw33:G
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publicList getItems(){ E(4w5=8TI
return items; }G'XkoI&
} Od{jt7 <j#
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publicvoid setItems(List items){ #{*LvI&
this.items = items; &RO7{,`
} oa`#RC8N
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publicint getPageSize(){ ,Dp0fauJ
return pageSize; c)~h<=)
} fF;h V
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publicvoid setPageSize(int pageSize){ P!e= b-T
this.pageSize = pageSize; W5SN I>|E
} 1nI^-aQ3
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publicint getTotalCount(){ |^( M{
return totalCount; pRi<cO
} $1Z6\G O
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publicvoid setTotalCount(int totalCount){ H}ZQ?uK;
if(totalCount > 0){ ho.(v;
this.totalCount = totalCount; Ef@,hX
int count = totalCount / U| 5-0 u5
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pageSize; 8-Me.2K
if(totalCount % pageSize > 0) <f>akT,W
count++; *Y6xvib9*
indexes = newint[count];
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for(int i = 0; i < count; i++){ Zu/<NC
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indexes = pageSize * \/5RL@X}
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} Eu,`7iQ?(
}else{ nxo+?:**
this.totalCount = 0; ig+4S[L~n
} 9 OT,TpA
} :/N+;- 18
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publicint[] getIndexes(){ V/%~F6e
return indexes; o:p
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} w$ fJ4+
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publicvoid setIndexes(int[] indexes){ S\#1 7.=
this.indexes = indexes; HM9fjl[
} \6!W05[ Q
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publicint getStartIndex(){ Jn&7C
return startIndex; }q[Bd
} mUoIJ3fv_,
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publicvoid setStartIndex(int startIndex){ )>a B
if(totalCount <= 0) 1;F`c`0<
this.startIndex = 0; # Su~`]
elseif(startIndex >= totalCount) .qv'6G
this.startIndex = indexes qxOi>v0\H
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[indexes.length - 1]; WT\<.Py
elseif(startIndex < 0) a;AzY'R
this.startIndex = 0; <wd]D@l7r
else{ >SbK.Q@ei
this.startIndex = indexes ??&<k
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[startIndex / pageSize]; Kg\R+i@#<
} /RnTQ4
} .ic:`1
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publicint getNextIndex(){ d^E [|w;
int nextIndex = getStartIndex() + 1fU,5+PH
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pageSize; KKe8
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if(nextIndex >= totalCount) <@v]H@E
return getStartIndex(); WYcA8X/
else ay
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return nextIndex; *Mc7f ?H
} ?#A]{l
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publicint getPreviousIndex(){ `{v?6:G:Q
int previousIndex = getStartIndex() - b\7iY&.C|
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pageSize; kS5_
if(previousIndex < 0) KJn!Ap
return0; zmuMWT;
else nk"NmIf
return previousIndex; rZXrT}Xh{W
} W#fZ1E6
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} 6?tlU>A2s
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抽象业务类 zw<p74DH
java代码: u^Ku;RQo
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/** z+}QZ>
* Created on 2005-7-12 ]va>ex$d
*/ 7R.Q
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package com.javaeye.common.business; WUc#)EEM)
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import java.io.Serializable; Vgb *% I
import java.util.List; O43YY2
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import org.hibernate.Criteria; ocbB&
import org.hibernate.HibernateException; +yob)%
import org.hibernate.Session; 620%Z*
import org.hibernate.criterion.DetachedCriteria; `?g`bN`Vn
import org.hibernate.criterion.Projections; }T^cEfX
import Qhi '')Q
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org.springframework.orm.hibernate3.HibernateCallback; g>0XxjP4
import 63|+2-E2Q
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org.springframework.orm.hibernate3.support.HibernateDaoS n6d9\
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upport; c\6+=\
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import com.javaeye.common.util.PaginationSupport; #ge)2
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public abstract class AbstractManager extends ,
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HibernateDaoSupport { 9//+Bh
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privateboolean cacheQueries = false; r"2V
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privateString queryCacheRegion; ne61}F"E
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publicvoid setCacheQueries(boolean L9Z;:``p
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cacheQueries){ X{n- N5*
this.cacheQueries = cacheQueries; )D'^3)FF
} f'I z
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publicvoid setQueryCacheRegion(String ?&LZB}1R
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queryCacheRegion){ 8(.mt/MR
this.queryCacheRegion = x^|V af
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queryCacheRegion; hUQ,z7-
} Cz4)Yz
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publicvoid save(finalObject entity){ -LDCBc"
getHibernateTemplate().save(entity); G$'jEa<:u
} gj\)CBOv
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publicvoid persist(finalObject entity){ -[= drj9I
getHibernateTemplate().save(entity); PiV7*F4qI.
} ^JI o?R
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publicvoid update(finalObject entity){ D'Z|}(d&
getHibernateTemplate().update(entity); O20M[_S
} |9"p|6G?B
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publicvoid delete(finalObject entity){ VL[R(a6c
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getHibernateTemplate().delete(entity); YY?a>j."a
} BR'I+lQ
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publicObject load(finalClass entity, nA|.t[v
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finalSerializable id){ DjU9
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return getHibernateTemplate().load 1Z[/KJ
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(entity, id); 9ukg }_Hx
} 7iHK_\t n
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publicObject get(finalClass entity, @i^~0A#q*
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finalSerializable id){ <Dx]b*H
return getHibernateTemplate().get `cx]e
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(entity, id); UgWs{y2SE.
} Ladsw
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publicList findAll(finalClass entity){ =9kN_:-
return getHibernateTemplate().find("from bs9aE<j
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" + entity.getName()); `/Nm
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} |uW:r17
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publicList findByNamedQuery(finalString e4~>G?rM_
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namedQuery){ qQ!1t>j+H
return getHibernateTemplate /-6S{hl9Ne
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().findByNamedQuery(namedQuery); 0l;<5
} kNu'AT#3|
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publicList findByNamedQuery(finalString query, 3] 1-M
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finalObject parameter){ \5Vde%!$Z
return getHibernateTemplate X=8Y%
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().findByNamedQuery(query, parameter); pT?Q#,fh
} jGrN\D?h
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publicList findByNamedQuery(finalString query, \c[IbL07
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finalObject[] parameters){ 9w9jpe#
return getHibernateTemplate ~[k%oA%W
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().findByNamedQuery(query, parameters); T32BnmB{
} eMRar<)+#*
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publicList find(finalString query){ m\/ Tj0e
return getHibernateTemplate().find \D>$aLO*?
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(query); Av0y?oGH
} K
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publicList find(finalString query, finalObject }HEvr)v9
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parameter){ 7FN<iI&7\
return getHibernateTemplate().find #k3t3az2{
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(query, parameter); Nr2 C@FU:0
} Gu=STb
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public PaginationSupport findPageByCriteria 5unG#szq
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(final DetachedCriteria detachedCriteria){ 5 ,0d
return findPageByCriteria E&yD8=vw
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); iVB^,KQ@
} W&h[p_0
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public PaginationSupport findPageByCriteria Qr#1 u
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(final DetachedCriteria detachedCriteria, finalint reo{*)%
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startIndex){ ZxGP/D
return findPageByCriteria R];Oxe
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(detachedCriteria, PaginationSupport.PAGESIZE, 4Ij-Ilg)%
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startIndex); *9ywXm&?
} X5YiFLH>y\
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public PaginationSupport findPageByCriteria +Taa!hfys
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(final DetachedCriteria detachedCriteria, finalint %tA57Pn>
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pageSize, :5GZ \Z8F
finalint startIndex){ TJ?g%
return(PaginationSupport) /8@m<CW2Y
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getHibernateTemplate().execute(new HibernateCallback(){ SFH-^ly&D
publicObject doInHibernate nZR!*$}A
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(Session session)throws HibernateException { w^K^I_2ge
Criteria criteria = P`U<7xF~
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detachedCriteria.getExecutableCriteria(session); 9ykM3
int totalCount = A`O <6
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((Integer) criteria.setProjection(Projections.rowCount xChI,~i
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()).uniqueResult()).intValue(); P+e KZo
criteria.setProjection b(GFMk
8:ggECD
(null); I
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List items = kfC0zd+
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criteria.setFirstResult(startIndex).setMaxResults ^[TV;9I*
[n,?WwC
(pageSize).list(); 2k7bK6=nm
PaginationSupport ps = Hv#q:R8
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new PaginationSupport(items, totalCount, pageSize, B%<e FFV\
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startIndex); B\j~)vg
return ps; `ia %)@
} )tZ`K
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}, true); 8uG0^h}
} i~=s^8n`l
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public List findAllByCriteria(final kD~uGA
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DetachedCriteria detachedCriteria){ t7#lsd`_
return(List) getHibernateTemplate (VHND%7P
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().execute(new HibernateCallback(){ T!q_/[i~7
publicObject doInHibernate P1 +"v*
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(Session session)throws HibernateException { 4dhqLVgL{
Criteria criteria = {'3D1#SK
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detachedCriteria.getExecutableCriteria(session); X\GM/A
return criteria.list(); f%fa{
} u,i]a#K
}, true); ~P1_BD(
} pD`/_-=^h
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public int getCountByCriteria(final H~+xB1
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DetachedCriteria detachedCriteria){ mPt)pn!rA
Integer count = (Integer) Jgx8-\8
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getHibernateTemplate().execute(new HibernateCallback(){ p,#6
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publicObject doInHibernate Z}Cqd?_')
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(Session session)throws HibernateException { U ^#?&u
Criteria criteria = o\4t4}z~'f
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detachedCriteria.getExecutableCriteria(session); @6.]!U4w
return (9.yOc4
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criteria.setProjection(Projections.rowCount XCPb9<L
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()).uniqueResult(); 04-Zvp2
} ofCVbn
}, true); uCUu!Vfeg
return count.intValue(); 8fO8Dob]\Y
} -{x(`9H;
} )mD\d|7f
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用户在web层构造查询条件detachedCriteria,和可选的 ,VG9)K1K
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [b`$\o'-
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PaginationSupport的实例ps。 y9
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ps.getItems()得到已分页好的结果集 ZQLB`n@
ps.getIndexes()得到分页索引的数组 -Op@y2+c
ps.getTotalCount()得到总结果数 XARSGAuw
ps.getStartIndex()当前分页索引 Ec.)!Hu
ps.getNextIndex()下一页索引 jeFN*r_
ps.getPreviousIndex()上一页索引 Ar~{= X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7j R7
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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 Nh :JU?h
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一下代码重构了。 pP
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我把原本我的做法也提供出来供大家讨论吧: I$Eg$q
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首先,为了实现分页查询,我封装了一个Page类: 6m\*]nOy4
java代码: 3Pa3f >}-
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/*Created on 2005-4-14*/ * S{\#s
package org.flyware.util.page; W9+h0A-
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/** ndB@J*Imu
* @author Joa K9}jR@jy$
* 2}|vWKej{
*/ B~BUWWMfp
publicclass Page { W=M<
c@
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/** imply if the page has previous page */ i!y\WaCp
privateboolean hasPrePage; iPNd!_
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/** imply if the page has next page */ BMe72
privateboolean hasNextPage; 0A@-9w=u
6J]~A0vsi}
/** the number of every page */ =cknE=
privateint everyPage; pO5v*oONz+
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/** the total page number */ i{4'cdr?
privateint totalPage; #<D@3ScC
37,L**Dgs
/** the number of current page */ =CGD
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privateint currentPage; HI7]%<L
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/** the begin index of the records by the current ,WzG.3^m
+q$xw}+PK
query */ Am]2@ESUP
privateint beginIndex; Cbazwq
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/
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/** The default constructor */ WFQ*s4 R(
public Page(){ AfuXu@UZ_/
7=; D0SS
} =I
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/** construct the page by everyPage 4o)(d=q
* @param everyPage rDK;6H:u{
* */ ab8oMi`z
public Page(int everyPage){ 0EcC
this.everyPage = everyPage; ecM4]U
} 3w[<cq.!
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/** The whole constructor */ 0\8*S3,q
public Page(boolean hasPrePage, boolean hasNextPage, HTR "mQ
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int everyPage, int totalPage, pil0,r
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int currentPage, int beginIndex){ H={O13
this.hasPrePage = hasPrePage; rC* sNy2
this.hasNextPage = hasNextPage; D!l [3
this.everyPage = everyPage; "#_)G7W+e
this.totalPage = totalPage; 5bu[}mJ
this.currentPage = currentPage; o|zrD~&$
this.beginIndex = beginIndex; >C*?17\
} mf
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/** Nb|3?c_
* @return h(+m<J
* Returns the beginIndex. BLl%D
*/ F[o+p|nF
publicint getBeginIndex(){ 0~PXa(!^K
return beginIndex; &KOG[tv
} lp37irI:
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/** XwHu:v'=
* @param beginIndex }a #b$]Y
* The beginIndex to set. }mtC6G41Q
*/ Ak%no3:9
publicvoid setBeginIndex(int beginIndex){ twYB=68
this.beginIndex = beginIndex; tu?Z@W/
} "/ a*[_sV
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/** 8|S1|t,
* @return Allt]P>
* Returns the currentPage. 1`2);b{@
*/ V8KTNt%
publicint getCurrentPage(){ pAUfG^v
return currentPage; 'NG^HLD/
} BCa90
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/** IDiUn!6Q
* @param currentPage )DklOEO
* The currentPage to set. qJbhPY8Ak
*/ }e/[$!35
publicvoid setCurrentPage(int currentPage){ t9$AvE#a!=
this.currentPage = currentPage; c|R3,<Q]
} @>
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/** @2%VU#!m
* @return Vx\#+)4
* Returns the everyPage. k?|F0e_
*/ QJ(e*/
publicint getEveryPage(){ Chb4VoE
return everyPage; lo>-}xd
} vBCZ/F[
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/** $Kw"5cm
* @param everyPage )z*$`?)k
* The everyPage to set. gR_b~^
*/ I")"s
publicvoid setEveryPage(int everyPage){ 8^ ~ZNU-~v
this.everyPage = everyPage; c@ZkX]g
} q=E}#[EgY
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/**
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* @return 8^f[-^%
* Returns the hasNextPage. K9z_=c+
*/ G7kFo6Cb
publicboolean getHasNextPage(){ O7<V@GL+
return hasNextPage; |+4E
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} JG+g88
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/** ^B"_b?b
* @param hasNextPage 8 *(W |J
* The hasNextPage to set. ETH#IM8J
*/ [(e`b
publicvoid setHasNextPage(boolean hasNextPage){ 8L9S^ '
this.hasNextPage = hasNextPage; s$nfY.C
} <x%my4M
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/** i]^*J1a
* @return 8`LLHX1|
* Returns the hasPrePage. -"JE-n
*/ E/ed0'|m
publicboolean getHasPrePage(){ dE9aE# o
return hasPrePage; cdU
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} j"$b%|
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/** 0,D9\ Ebd
* @param hasPrePage 7zkm
* The hasPrePage to set. }"; hz*a
*/ ]I*#R9
publicvoid setHasPrePage(boolean hasPrePage){ 7_'k`J@_
this.hasPrePage = hasPrePage; :-'ri Ry
} [r<
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MvjwP?J]
/** []fj~hj
* @return Returns the totalPage. E6&uZr
* +WEO]q?K
*/ 93p9?4;n-
publicint getTotalPage(){ >8HRnCyp/
return totalPage; Z_ *ZUN?B
} N|#x9mE
E=U^T/
/** 1ZH8/1gWI
* @param totalPage f*H}eu3/j
* The totalPage to set. ++RmaZ
*/ UtW3KvJ#=
publicvoid setTotalPage(int totalPage){ i~PZvxt
this.totalPage = totalPage; Q^5 t]HKn
} 2!& ;ZcT,
KB-#):'
} Wv'B[;[)
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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 sy#j+gZ
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个PageUtil,负责对Page对象进行构造: w9?wy#YI
java代码: k5\
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/*Created on 2005-4-14*/ +[nYu)puP
package org.flyware.util.page; BHBR_7
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import org.apache.commons.logging.Log; `)_FO]m}jS
import org.apache.commons.logging.LogFactory;
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/** VFp)`+8
* @author Joa Ho{?m^
* :EAfD(D{)
*/ VH*(>^OfF
publicclass PageUtil { E )SOcM)
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privatestaticfinal Log logger = LogFactory.getLog q:eAL'OkM
"[Lp-4A\
(PageUtil.class); `l@t3/
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/** 4h@of'
* Use the origin page to create a new page K_Gf\x
* @param page \3UdC{~
* @param totalRecords dNmX<WXG
* @return
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*/ Yhdt8[ 2
publicstatic Page createPage(Page page, int 4ov~y1Da)
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totalRecords){ g9`ytWmM
return createPage(page.getEveryPage(), v<4X;4p^
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page.getCurrentPage(), totalRecords); [IW7]Fv<F
} <0MUn#7'
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/** *gKr1}M
* the basic page utils not including exception {=Y&q~:8v
=z dti'2{4
handler &0blHDMj{#
* @param everyPage 8BdeqgU/_
* @param currentPage g9Ll>d)tE3
* @param totalRecords @T T[H*,
* @return page n[7zK'%Dxg
*/ 'f!Jh<i
publicstatic Page createPage(int everyPage, int mcracj[B
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currentPage, int totalRecords){ 8gdOQ=a
everyPage = getEveryPage(everyPage); [!$>:_Vq/
currentPage = getCurrentPage(currentPage); 1Sr}2@>
int beginIndex = getBeginIndex(everyPage, ]].21
y%AJ>@/;
currentPage); MS)bhZvO
int totalPage = getTotalPage(everyPage, W>49,A,q
Lr &tpB<
totalRecords); #v<+G=r*O
boolean hasNextPage = hasNextPage(currentPage, b
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_69\#YvCG
totalPage); Sy55w={
boolean hasPrePage = hasPrePage(currentPage); bvKi0-
/J:j'6
returnnew Page(hasPrePage, hasNextPage, aV.<<OS
everyPage, totalPage, t~M_NEPxV
currentPage, P&VI2k
F'!}$oT"
beginIndex); V _,*
} Ws@s(5r
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privatestaticint getEveryPage(int everyPage){ xg&vZzcl
return everyPage == 0 ? 10 : everyPage; I1jF`xQ&0
} r+crE %-
~]Jfg$'
privatestaticint getCurrentPage(int currentPage){ `x3c},'@k
return currentPage == 0 ? 1 : currentPage; $Re
%+2c
} dX*PR3I-3
:csLZqn[
privatestaticint getBeginIndex(int everyPage, int b7/4~_s
^EZoP:x(oE
currentPage){ c`cPGEv
return(currentPage - 1) * everyPage; 4{&
} UF
tTt`N2
HV?@MBM
privatestaticint getTotalPage(int everyPage, int j~0hAKHG
~}fpe>M:
totalRecords){ TaH9Nu
int totalPage = 0; S6uBk"V!
S_zE+f+
2
if(totalRecords % everyPage == 0) ;S/fe(C
totalPage = totalRecords / everyPage; {^F_b% a4z
else {fWZ n
totalPage = totalRecords / everyPage + 1 ; AiuF3`Xa
9j/B3CjW
return totalPage; LdL< 5Q[
} H4U;~)i
,fbO}
privatestaticboolean hasPrePage(int currentPage){
^B<jMt
return currentPage == 1 ? false : true; ev`p!p
} \VW.>@s~
wp$=lU{B
privatestaticboolean hasNextPage(int currentPage, pdM|dGq^
LS;kq',
int totalPage){ 'sC{d&c
return currentPage == totalPage || totalPage == sy~mcH:%+
7ORwDR,`5
0 ? false : true; zK}.Bhj#
} 9E+^FZ e
7J)-WXk
4&tY5m>
} |e!Sm{#!
Xa36O5$4]9
Q"KH!Bu%P
<=p"ck@
R]dc(D
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 r*$KF!-dg
<I7UyCAF
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 U^.$k-|k
~Oolm_+{}
做法如下: Mb-C DPT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 wI)W:mUZZ
C0e<
_6p=
的信息,和一个结果集List: Rzz*[H
java代码: O*CKyW_$t
u4%-e)$X
Q16RDQ*
/*Created on 2005-6-13*/ V /|@
package com.adt.bo; 7p|Pv;wp|
{R(q7ALR
import java.util.List; 778a)ZOzb
${e{#
import org.flyware.util.page.Page; h|wyvYKZ
)U5AnL
/** k9a-\UIMet
* @author Joa (ue;O~
*/ N'IzHyo.
publicclass Result { F&Q:1`y
HyZh27PE
private Page page; [<6ez;2q'
+YXyfTa
private List content; eP6>a7gc
fy7]I?vm@
/** eR?`o !@y
* The default constructor GDhg
VOW(
*/ @N34 Q-l
public Result(){ }{HlY?S
super(); zK?[6n89f
} G3m+E;o1
GkVV%0;&J1
/** Iq(BH^K
* The constructor using fields ZxY%x/K
* ^C_ ;uz
* @param page o#CNr5/
* @param content <\Lii0hi!
*/ J&2cf#
public Result(Page page, List content){ uK1DC i
this.page = page; iU5M_M$G
this.content = content; 5V8WSnO
} L~=h?C<
\\xoOA.
/** [Q6PFdQ_JT
* @return Returns the content. ;X*I,g.+H
*/ 274F+X
publicList getContent(){
~p<w>C9
return content; "]B:QeMeF!
} wa2?%y_G
ZuH@qq\
/** Z0 @P1
* @return Returns the page. LB$#]
Z
*/ ,Y ./9F
public Page getPage(){ }}G`yfs}r
return page; 4zzJ5,S 1
} f0S$p
R
=~yRgGwJ
/** b"k1N9
* @param content +~Wg@
* The content to set. {el[W,CT#
*/ N3"O#C
public void setContent(List content){ crTRfqF
this.content = content; WCRGqSr4
} \I"n~h^_
N.(wR
/** RA^6c![
* @param page M-7^\wXTA
* The page to set. NAg m?d
*/ _D.4=2@|l8
publicvoid setPage(Page page){ q|h#J}\
this.page = page; `cgyiJ
} \
]v>#VXr_
} P.#@1_:gC
ZW>iq M^9
h\-3Y U
q[}W&t,
|pgrR7G'
2. 编写业务逻辑接口,并实现它(UserManager, `?=Y^+*!-
Ndmki
7A
UserManagerImpl) ?hBj q
java代码: ^J~5k,7jX
d
RIu A)0s
dj-/%MU
/*Created on 2005-7-15*/ *{x8@|K8
package com.adt.service; lq}m0}9<
i4Da 'Uk
import net.sf.hibernate.HibernateException; :6TLT-B
pddumbp
import org.flyware.util.page.Page; T|k_$LH
tfIUH'Ez>
import com.adt.bo.Result; jI/#NCKE
xcE2hK/+
/** __%){j6
* @author Joa WU\Bs2
*/ aOhi<I`*
publicinterface UserManager { UX24*0`\~
&iO53I^r/
public Result listUser(Page page)throws q~. .Z Y`7
blx"WVqo
HibernateException; ak_n
%6Y\4Fe
} fA)4'7UT
P" aw--f(
R+# g_"1@p
xey?.2K1A
^XT;n
java代码: *4y0Hq
*RD<*l
Il]p >B
/*Created on 2005-7-15*/ }hA)p:
package com.adt.service.impl; LS/ZZAN u
.efbORp
import java.util.List; g?rK&UTU
D\Fu4Eg
import net.sf.hibernate.HibernateException; ]D_
AZI
.h-k*F0Ga)
import org.flyware.util.page.Page; ~? n)/i("
import org.flyware.util.page.PageUtil; J\?d+}hynX
F%I*m^7d
import com.adt.bo.Result; LIRL`xU7
import com.adt.dao.UserDAO; !DBaC%TGC
import com.adt.exception.ObjectNotFoundException; ^Sc48iDc
import com.adt.service.UserManager; %GigRA@no
eB_ M *+^
/** Q"k #eEA
* @author Joa Tffdm
*/ W]5sqtF;6
publicclass UserManagerImpl implements UserManager { u vyvy
DI\^&F)3T2
private UserDAO userDAO; $aY:Z_s
r12e26_Ab
/** T^@P.zX
* @param userDAO The userDAO to set. m^;A]0h+
*/ Uc0Sb
publicvoid setUserDAO(UserDAO userDAO){ ug?#Oa
this.userDAO = userDAO; Ym
wb2]M
} Bg}(Sy
@rlL'|&X*
/* (non-Javadoc) oF.H?lG7`
* @see com.adt.service.UserManager#listUser *40Z}1ng
J';XAB }
(org.flyware.util.page.Page) yb-/_{Y
*/ q;<Q-jr&O
public Result listUser(Page page)throws M(.]?+
e
ls&_BPE
HibernateException, ObjectNotFoundException { @l?2",
int totalRecords = userDAO.getUserCount(); k(wJ6pc
if(totalRecords == 0) W4S]2P>T
throw new ObjectNotFoundException u\@L|rh
x=3+@'
("userNotExist"); J:2Su1"ODh
page = PageUtil.createPage(page, totalRecords); <Q?_],ip
List users = userDAO.getUserByPage(page); KDYyLkI dr
returnnew Result(page, users); {ud^+I&
} lPn&,\9@~
Cz#3W8jV
} -P$E)5?^
Eq'oy~.oV
>}B~~C;
q^+Z>
'q*:+|"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Ge4tc
>Av%[G5=h#
询,接下来编写UserDAO的代码: et :v4^*f
3. UserDAO 和 UserDAOImpl: Ujss?::`G
java代码: W'M\DKJ?
AV?<D.<
nuX W/7M
/*Created on 2005-7-15*/ dIDs~
package com.adt.dao; bHH=MLZR:
(?pn2- Ip
import java.util.List; |cq%eN
pI{s
)|"
import org.flyware.util.page.Page; a3oSSkT
Mq$Nra
import net.sf.hibernate.HibernateException; ^Sz?c_<2P
kEs=N(
/** .
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* @author Joa N0G-/
*/ =v]eQIp
publicinterface UserDAO extends BaseDAO { G q
r(.
hy|X(m
publicList getUserByName(String name)throws fO{E65uA
"227 U)Q
HibernateException; },5_h0
)SYZ*=ezl.
publicint getUserCount()throws HibernateException; to*<W,I
))>)qav
publicList getUserByPage(Page page)throws ^NTOZ0x~#
`?L-{VtM3*
HibernateException; eX>X=Ku
-/#tQ~{gs
} o$r]Z1
ywV8s|o
|79!exVMBp
s(I7}oRWsL
{1
94u%'
java代码: p
}bTI5
V
F'!
OPN
M('cG
/*Created on 2005-7-15*/ 8_tMiIE-pS
package com.adt.dao.impl; YA>du=6y\
Th%1eLQ
import java.util.List; Tl3{)(ezx
0R2 AhA#
import org.flyware.util.page.Page; (&$|R\W.
Wwf#PcC]
import net.sf.hibernate.HibernateException; 5i$~1ZC
import net.sf.hibernate.Query; Yn}_"FO'
9c=_p'G3Fw
import com.adt.dao.UserDAO; K/u`Wz~A
SS;QPWRZ
/** ?WX&,ew~
* @author Joa Zh.fv-Ecp
*/ n]@+<TA<uA
public class UserDAOImpl extends BaseDAOHibernateImpl <nj[=C4v
v=|BqG`
implements UserDAO { OI.2C F
soZw""|v
/* (non-Javadoc)
Xze
* @see com.adt.dao.UserDAO#getUserByName s%z'1KPS
_rqOzE)
(java.lang.String) )8yee~+TN
*/ OR^Wd
publicList getUserByName(String name)throws -j[n^y'v
5@Q4[+5&_
HibernateException { *[7,@S/<F
String querySentence = "FROM user in class v[6 BESu
+2w54X%?M
com.adt.po.User WHERE user.name=:name"; `R^g[0 w'
Query query = getSession().createQuery 0{Kl5>Z9M
,\DB8v6l\A
(querySentence); tGd<{nF% 2
query.setParameter("name", name); |b/J$.R
return query.list(); IR%a+;Xs
} 9kP!O_
7-ba-[t#A
/* (non-Javadoc) 9VN@M
* @see com.adt.dao.UserDAO#getUserCount() <E
BgHD)
*/ Prhq ~oI4
publicint getUserCount()throws HibernateException { 4T9hT~cT7
int count = 0; %~ecrQ;
String querySentence = "SELECT count(*) FROM 4W.;p"S2
%`}CbD6
user in class com.adt.po.User"; uPV,-rm[F_
Query query = getSession().createQuery $_Qo
!r.}y|t?;
(querySentence); @WEem(@
count = ((Integer)query.iterate().next ojVpw4y.
BPrA*u}T
()).intValue(); 6EK+] 0
return count; ja7Zv[
} %TG$5')0
0 \LkJ*i
/* (non-Javadoc) =pcj{B{qa
* @see com.adt.dao.UserDAO#getUserByPage >Fld7;L?<
Mn~A;=%qF
(org.flyware.util.page.Page) 7Nwi\#o
*/ 0v0Y(
Mo@
publicList getUserByPage(Page page)throws vEzzdDwi6
jD^L <
HibernateException { 9v
cUo?/
String querySentence = "FROM user in class XU9=@y+|v
\Zf&&7v
com.adt.po.User"; Ip4NkUI3T
Query query = getSession().createQuery sp**Sg)
g@Ni!U"_c
(querySentence); /"CKVQ
query.setFirstResult(page.getBeginIndex()) HxY,R^
.setMaxResults(page.getEveryPage()); h0.Fstf]
return query.list(); ;6b#I$-J-
} @gi
Y
a
LmVOL{
} ?3}UO:B
Xe+&/J5b
<YeF?$S}
G<jpJ
U-FA^c;
至此,一个完整的分页程序完成。前台的只需要调用 6>=>Yj
)1fQhdO}x
userManager.listUser(page)即可得到一个Page对象和结果集对象 ri JyH;)
@IiT8B
的综合体,而传入的参数page对象则可以由前台传入,如果用 HnP;1Gi
dWqFP
webwork,甚至可以直接在配置文件中指定。 X^|oY]D
zK-hNDFL{
下面给出一个webwork调用示例: U[A*A^$c}
java代码: Ab2g),;c
CY>NU
rIb[gm)Rk
/*Created on 2005-6-17*/ 5&X
package com.adt.action.user; Ve8!
==XP}w)m
import java.util.List; 9)l_(*F
n~&R_"mv(
import org.apache.commons.logging.Log; k9Sqp:l,
import org.apache.commons.logging.LogFactory; q6Q=Zo@
import org.flyware.util.page.Page; |Lhz^5/
_yWH\5@
import com.adt.bo.Result; Y$ChMf
import com.adt.service.UserService; R NA03
import com.opensymphony.xwork.Action; amBz75N{
3,vH:L4
/** :):Y6)giBD
* @author Joa /XSPVc<
*/ b(SV_.4,'
publicclass ListUser implementsAction{ #`p>VXBj!
$k`8Zx w
privatestaticfinal Log logger = LogFactory.getLog @^` <iTK&p
/M3D[aR<d
(ListUser.class); z'qVEHc)
7%E1F)%
private UserService userService; *(vq-IE\$
-YuvEm#f
private Page page; h+74W0
$
<y.D0^68
privateList users; O h"^
i9xv`Ev=R
/* W1@;94Sb~
* (non-Javadoc) X#3<hN*v
* `U g.c
* @see com.opensymphony.xwork.Action#execute() 6#KI?
6
*/ Agi1r]W
publicString execute()throwsException{ *cf"l
Result result = userService.listUser(page); 8zc!g|5"
page = result.getPage(); +
kF[Oh#
users = result.getContent(); P+b^;+\1s
return SUCCESS; %b{!9-n}
} ^ Wl/
*.*:(7`
/** DO\EB6xH>%
* @return Returns the page. J7\q#] ?
*/ UeICn@)\y
public Page getPage(){ $1?X%8V
return page; ~d8>#v=Q`
} e6R"W9
m4DH90~a8
/** 2Y4&Sba^Y
* @return Returns the users. Qwa"AY5pW
*/ cik@QN<[0
publicList getUsers(){ -*lP1Nbp
return users; A C^[3
} Q*C4
q`
zrew:5*uZ
/** .cF$f4>2
* @param page 2`I;f/Sd
* The page to set. 1!`768
*/ d8kwW!m+
publicvoid setPage(Page page){ e1loI8
this.page = page; BP[U`
!
} .V3Dql@z"
l1)pr{A
/** n`}&,UA$4
* @param users N 9&@,3
* The users to set. :b;1P@W<
*/ CCY|FK
publicvoid setUsers(List users){ k@aP&Z~
this.users = users; ]'h)7
} #5C3S3e=
O|RO
j
/** DjIswI1I
* @param userService X{xJ*T y'
* The userService to set. ~|9LWp_
*/ ]2%P``Yj
publicvoid setUserService(UserService userService){ DP_Pqn8p&M
this.userService = userService; iFCH$!
} I|IlFu?O=
} 4) iEj
E
E|zY%
%gMpV
R$fIb}PDr
T+nC>}*jgJ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0o|,& K
_A|\.(t
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 g$"eI/o
S.)7u6/_!
么只需要: N&ql(#r
java代码: e-cb?.WU?
gwaC?tf[
/mwr1GU
<?xml version="1.0"?> un^IQMIh
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork
_O;~
}N4u
fJw=7t-t
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,*Z[P%<9
WJU NJN
1.0.dtd"> OPY/XKyY,
'HWgvmw(
<xwork> ]2Fo.n
FFeRE{,
<package name="user" extends="webwork- |J Q:.h
;v+uv f
interceptors"> `O=;E`ep
z#J/*712
<!-- The default interceptor stack name cNr][AzU@
gZEA;N:H%<
--> DVoV:pk
<default-interceptor-ref q&$0i
CotMV^
name="myDefaultWebStack"/> 06@0r
To8v#.i
<action name="listUser" }Q=se[((
Zc3:9
class="com.adt.action.user.ListUser"> c^Gwri4
<param ,q@(L
&/hr-5k
name="page.everyPage">10</param> T{H#]BF<E
<result :iQ^1S`pH
fI
d)
name="success">/user/user_list.jsp</result> mYjiiql~
</action>
iRwW> a3/
9h38`*Im;
</package> u4#~
i0@
d)GkXll1D
</xwork> @oqi@&L'C
'Tf#S@o
30(m-D$K>9
r{!"%03H_
uU ?37V
S[hJ{0V
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 E"1;i
?tC}M;~
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。 YV3TxvXMR
h,'mN\6t
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Z:Y.":[
Qi
h
GA0F9.U
LJNie*
9 /Ai(
C|d!'"p
我写的一个用于分页的类,用了泛型了,hoho !:5`im;i
K?Xo3W%K
java代码: 1[/$ZYk:
d[RWkk5
P$6f +{
package com.intokr.util; :YJ7J4
[%iUg\'7d
import java.util.List; &X]=Qpl
,4>WLJDo
/** /Xu;/MMpd3
* 用于分页的类<br> x:n9dm
* 可以用于传递查询的结果也可以用于传送查询的参数<br>
TCKI
* 2.Eu+*UC
* @version 0.01 kJvy<(iG
* @author cheng ok>P [
&!
*/ `m@]
public class Paginator<E> { #1jtprc
privateint count = 0; // 总记录数 SCh7O}
privateint p = 1; // 页编号 61+pryW%g
privateint num = 20; // 每页的记录数 K*_{Rs0P
privateList<E> results = null; // 结果 V:(w\'wm
2 -p
/** ]EVe@
* 结果总数 c6Yf"~TD0
*/ <(bCz>o|
publicint getCount(){ R%)2(\
return count; RlslF9f
} j""y2c1
K?FX<PT
publicvoid setCount(int count){ A1|7(Sow
this.count = count; EBIa%,
} g]==!!^<D
'?`@7Eol
/** lC /Hib
* 本结果所在的页码,从1开始 l6S19Kv
* *< $c
=
* @return Returns the pageNo. s}[A4`EWH
*/ '!+P{
publicint getP(){ gI^L
9jE7
return p; (DG@<K,6
} ebO`A2V'(
rF8W(E_=
/** h+B'_`(
* if(p<=0) p=1 5D]30
* Fi?32e4KI5
* @param p bRK CY6
*/ wuBlFUSg
publicvoid setP(int p){ z<yNG/M1>U
if(p <= 0) e>?_)B4
p = 1; 7Ykj#"BZ
this.p = p; DnG/ n
} &O+sK4P
f!M[awj%
/** IDGQIg
* 每页记录数量 |5}rX!wS4
*/ ~),;QQ,
publicint getNum(){ r
1l/) ;
return num; l50|`
6t
} 08Pt(kzNA
,Lt~u_ lve
/** .g/ARwM}
* if(num<1) num=1 []A"]p
*/ ]k::J>84
publicvoid setNum(int num){ 4T-,'P{?
if(num < 1) 6?3/Ul}
num = 1; X
zi'Lu`
this.num = num; $zk^yumdE
} d]O_E4X*
lgkl? 0!
/** QvG56:M3
* 获得总页数 "8wf.nZ
*/ h`
irO5
publicint getPageNum(){ =~GE?}.o
return(count - 1) / num + 1; yCF"Z/.
} [+g(
<mv7HKVg
/** Je#!Wd
* 获得本页的开始编号,为 (p-1)*num+1 e-[>( n/[
*/ HG{&U:>)
publicint getStart(){ ~w
Zl2I
return(p - 1) * num + 1; ]dPVtk
} 0t#NMW
j3*M!fM9
/** 1fz*SIjG
* @return Returns the results. Ujce |>Wn
*/ BA~a?"HS
publicList<E> getResults(){ 'i@,~[Z4
return results; "C_T]%'Wm
} }1U#Ve,=_
2Pbe~[
public void setResults(List<E> results){ !MZ+- dpK
this.results = results; <Vz<{W3t
} GY oZ$p" C
ayV6m
public String toString(){ V~/.Y&WN
StringBuilder buff = new StringBuilder `^v4zWDK
Hze-Ob8
(); _LJ5o_-N
buff.append("{"); p]wP36<S!
buff.append("count:").append(count); F0@Qgk]\
buff.append(",p:").append(p); 54<6Dy f
buff.append(",nump:").append(num); lkV6qIj
buff.append(",results:").append K1:a]aU?Iu
{*N^C@
(results); ! mm5I#s
buff.append("}"); o[o:A|n
return buff.toString(); HV ;;
} u FMIY(vB
UQ5BH%EPb
} W@l+ciZ_
#;d)?
=K .r