Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 MKYXYR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b:nHcxDU<
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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 <5Jp2x#
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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
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分页支持类: 0FFx
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java代码: YN
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package com.javaeye.common.util; Brh<6Btl
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import java.util.List; R)"Y40nW
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publicclass PaginationSupport { )IGE2k|
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publicfinalstaticint PAGESIZE = 30; (DCC4%w"
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privateint pageSize = PAGESIZE; P"%i 4-S
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privateList items; -So&?3,\A@
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privateint totalCount; :cmfy6h]
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privateint[] indexes = newint[0]; SB1\SNB
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privateint startIndex = 0; xr)Rx{)3h
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public PaginationSupport(List items, int vIrLG1EK
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totalCount){ /I3#WUc;![
setPageSize(PAGESIZE); MC!K7ji
setTotalCount(totalCount); 4Wq{ch
setItems(items); `Njv#K} U
setStartIndex(0); !Jw
} Af:4 XSO6
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public PaginationSupport(List items, int R ;^[4<&
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totalCount, int startIndex){ twqjaFA>
setPageSize(PAGESIZE); BlS0I%SN
setTotalCount(totalCount); nn"!x|c
setItems(items);
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setStartIndex(startIndex); :<w3.(Z
} <L@0w8i`
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public PaginationSupport(List items, int Rx*T7*xg{
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totalCount, int pageSize, int startIndex){ 9}Tf9>qP>M
setPageSize(pageSize); kDJ5x8Q#
setTotalCount(totalCount); t$8f:*6(*
setItems(items); _cx}e!BK#
setStartIndex(startIndex); '+NmHu:q
} v9Oyboh(y
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publicList getItems(){ ;8;nY6Ie
return items; g6$X {
} *plsZ*Q8
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publicvoid setItems(List items){ E27wxMU
this.items = items; N\Byg jw|
} ~zFs/(k
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publicint getPageSize(){ zr?%k]A%UO
return pageSize; vbmSbZ"y
} fR}|CP
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publicvoid setPageSize(int pageSize){ _r5Q%8J
this.pageSize = pageSize; 59O;`y0
} )JTh=w4n|z
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publicint getTotalCount(){ X%xX3e'
return totalCount; B5u06O
} =M)>w4-
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publicvoid setTotalCount(int totalCount){ h{S';/=8
if(totalCount > 0){ `f}c 1
this.totalCount = totalCount; 9u lJZ\cQ
int count = totalCount / 9j:t}HV
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pageSize; @D-l_[
if(totalCount % pageSize > 0) &h-d\gMJ
count++; *'vX:n&t
indexes = newint[count]; 7am ._K
for(int i = 0; i < count; i++){ Q3\j4;jI(
indexes = pageSize * F'W{\4
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} 1b
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}else{ Z:09]r1
this.totalCount = 0; JJ q= {;
} ;_M .(8L
} n[CESo%[
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publicint[] getIndexes(){ W+&ZYN'E
return indexes; Vp\BNq_!s
} D|,d_W
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publicvoid setIndexes(int[] indexes){ BKIAc6
this.indexes = indexes; "{&\ nt
} eP|:b &
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publicint getStartIndex(){ ouK&H|'
return startIndex; bT*MJ7VVm
} S&8gZ~B
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publicvoid setStartIndex(int startIndex){ Z,qo
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if(totalCount <= 0) [ECSJc&i
this.startIndex = 0; U2=5Nt5
elseif(startIndex >= totalCount) wt[MzpR P
this.startIndex = indexes %F9%t
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[indexes.length - 1]; |!i3Y=X
elseif(startIndex < 0) RO=[Rr!
this.startIndex = 0; b[?6/#N
else{ /d9I2~}B
this.startIndex = indexes [#kfl
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[startIndex / pageSize]; QQ!%lbMK]
} 'N)&;ADx-G
} cfMj^*I
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publicint getNextIndex(){ 2I(0EBW
int nextIndex = getStartIndex() + 6*gMG3
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pageSize; Gn#5zx#l
if(nextIndex >= totalCount) 5Az=)q4Q
return getStartIndex(); <33[qt~
else ^E8&!s
return nextIndex; k/=J<?h0
} .%<oy"_
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publicint getPreviousIndex(){ ez&v"J
int previousIndex = getStartIndex() - !>Db
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pageSize; )TFaG[tj
if(previousIndex < 0) n'v[[bmu
return0; [MdVgJ9'
else HvN!_}[
return previousIndex; Y[i>
} di>"\On-
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}
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抽象业务类 )9 5&-Hs
java代码: {'E%SIRZ)
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/** 4 FW~Y
* Created on 2005-7-12 %N7b
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*/ eZIqyw
package com.javaeye.common.business; y!u)q3J0&
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import java.io.Serializable; ^](sCE7
import java.util.List; w<<>XIL
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import org.hibernate.Criteria; I!dA{INN
import org.hibernate.HibernateException; CO%7^}xSE,
import org.hibernate.Session; n@XI$>B
import org.hibernate.criterion.DetachedCriteria; B^P)(Nu+
import org.hibernate.criterion.Projections; UX;?~X
import E'j>[C:U
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org.springframework.orm.hibernate3.HibernateCallback; U748$%}]
import 8{#WF#
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org.springframework.orm.hibernate3.support.HibernateDaoS ci0)kxUBF
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upport; I;<0v@
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import com.javaeye.common.util.PaginationSupport; ~m8".Z"
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public abstract class AbstractManager extends $~!%Px)
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HibernateDaoSupport { C$(US8:{
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privateboolean cacheQueries = false; Qn(2UO!pD
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privateString queryCacheRegion; F&%@p&
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publicvoid setCacheQueries(boolean _VGAh:v
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cacheQueries){ kfr' P u
this.cacheQueries = cacheQueries; E;/WP!/.
} H?*EQK`7?0
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publicvoid setQueryCacheRegion(String B(7oHj.i2
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queryCacheRegion){ DDQ}&`s
this.queryCacheRegion = JFH3)Q
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queryCacheRegion; )'+" y~
} ~U(`XvR\4
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publicvoid save(finalObject entity){ b3F)$UQ
getHibernateTemplate().save(entity); Q)c3=.[>
} g = ~Y\$&
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publicvoid persist(finalObject entity){ k>E^FB=
getHibernateTemplate().save(entity); q;Tdqv!Ju
} WD#
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publicvoid update(finalObject entity){ WJWi'|C4
getHibernateTemplate().update(entity); k-IL%+U
} p[R4!if2
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); M2H +1ic
} 60,z! Vv
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publicObject load(finalClass entity, \c}_!.xj"
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finalSerializable id){ k%uR!cL
return getHibernateTemplate().load xfoQx_]$Im
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(entity, id); scX'>\w&c
} #lAC:>s3U
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publicObject get(finalClass entity, ?M!Mb-C[
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finalSerializable id){ V %h,JA
return getHibernateTemplate().get p0*qv"lA
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(entity, id); 4>
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} q9Zp8&<EqH
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publicList findAll(finalClass entity){ F!7dGa$
return getHibernateTemplate().find("from /2^"c+/'p
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" + entity.getName()); =LXjq~p
} YP
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publicList findByNamedQuery(finalString .3
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namedQuery){ a+'k#m
return getHibernateTemplate n*A?>NV
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().findByNamedQuery(namedQuery); "I)/|x\G*
} V>Dqw!
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publicList findByNamedQuery(finalString query, F m?j-'
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finalObject parameter){ q QcQnd2K
return getHibernateTemplate Fn>KdoByN
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().findByNamedQuery(query, parameter); 4)"S/u
} dG&^M".(
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publicList findByNamedQuery(finalString query, ~c,CngeL0
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finalObject[] parameters){ Gj_7wP$
return getHibernateTemplate 5(zdM)Y7
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().findByNamedQuery(query, parameters); |I[/Fl:
} a\m_Q{:
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publicList find(finalString query){ BG|m5f
return getHibernateTemplate().find \?v?%}x
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(query); K;z$~;F
} (E;+E\E
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publicList find(finalString query, finalObject *+OS;R1<
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parameter){ =yF]#>Ah
return getHibernateTemplate().find :V3z`}Rl
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(query, parameter); :)Pj()Os|
} zu3Fi= |0
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public PaginationSupport findPageByCriteria (>
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(final DetachedCriteria detachedCriteria){ l-Be5?|{_
return findPageByCriteria GO?hB4 9T
*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); .k:heN2-x
} l+#J oc<8
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public PaginationSupport findPageByCriteria X+1Mv
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(final DetachedCriteria detachedCriteria, finalint 80zpRU"
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startIndex){ V&*|%,q
return findPageByCriteria iYZn`OAx
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(detachedCriteria, PaginationSupport.PAGESIZE, y\omJx=,
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startIndex); &szYa-K*
} bwM?DY
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public PaginationSupport findPageByCriteria ,<N{Y[n]e
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(final DetachedCriteria detachedCriteria, finalint QM![tZt%;
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pageSize, a:8 MoH 4
finalint startIndex){ ;4U"y8PVTh
return(PaginationSupport) l?QA;9_R'
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getHibernateTemplate().execute(new HibernateCallback(){ ]#Cc7wa
publicObject doInHibernate 9: .m]QN
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(Session session)throws HibernateException { eF]8Ar1
Criteria criteria = Y)@Y$_
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detachedCriteria.getExecutableCriteria(session); NRny]!
int totalCount = xP_/5N=f
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((Integer) criteria.setProjection(Projections.rowCount ,]:Gn5~
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()).uniqueResult()).intValue(); D Qz+t
criteria.setProjection k 3H0$1
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(null); =&6sU{j*
List items = .%y'q!?
IITUM)
criteria.setFirstResult(startIndex).setMaxResults 41R6V>e@9J
,jEc4ih4
(pageSize).list(); HCsd$M;Hbv
PaginationSupport ps = 5x%Blkx
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new PaginationSupport(items, totalCount, pageSize, F~i ~%f,
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startIndex); JO`r)_
return ps; J$sBfOD
} 5RvE ),
}, true); 1
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} PWZd<
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public List findAllByCriteria(final s;YbZ*oaMe
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DetachedCriteria detachedCriteria){ }% f7O
return(List) getHibernateTemplate 0
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().execute(new HibernateCallback(){ xu_,0ZT]{
publicObject doInHibernate 'B{FRK
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(Session session)throws HibernateException { A+!,{G
Criteria criteria = r88De=*
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detachedCriteria.getExecutableCriteria(session); Cdib{y<ji
return criteria.list(); L-}J=n\
} 5wmd[YL
}, true); #GLW3}
} ,%
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public int getCountByCriteria(final oz>2P.7
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DetachedCriteria detachedCriteria){ $%q=tn'EX
Integer count = (Integer) nX 9]dz
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getHibernateTemplate().execute(new HibernateCallback(){ v+"4YIN
publicObject doInHibernate w6Nnx5Ay
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(Session session)throws HibernateException { `:Gzjngc
Criteria criteria = JC%&d1
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detachedCriteria.getExecutableCriteria(session); 5LB{b]w7m
return 3ZI7;Gw
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criteria.setProjection(Projections.rowCount C6[W/,eS
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()).uniqueResult(); &:g:7l]g
} n
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}, true); {@vnKyf^K
return count.intValue(); V0v,s^\H
} 7jIBE
} BH1h2OEe#
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用户在web层构造查询条件detachedCriteria,和可选的 7n6g;8xE
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 hp)^s7H
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PaginationSupport的实例ps。 _yv#v_Z
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ps.getItems()得到已分页好的结果集 >i,_qe?V:w
ps.getIndexes()得到分页索引的数组 1*9.K'
ps.getTotalCount()得到总结果数 4_kN';a4Q
ps.getStartIndex()当前分页索引 tLWw<)t
ps.getNextIndex()下一页索引 Bj1%}B
ps.getPreviousIndex()上一页索引 R
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ztg_='n
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 \"oZ\_
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一下代码重构了。 T:$^1"\
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我把原本我的做法也提供出来供大家讨论吧: (MI>7| ';
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首先,为了实现分页查询,我封装了一个Page类: qK a}O*
java代码: GYfOwV!zB
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/*Created on 2005-4-14*/ HCs^?s8Pp
package org.flyware.util.page; +QU>D:l
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/** (c(F1=K
* @author Joa FKTF?4+\U
* ;"Kgg:K>W
*/ 5,1<A@H
publicclass Page { 0cq@lT6
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/** imply if the page has previous page */ A/>Q5)
privateboolean hasPrePage; (QiA5!wg
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/** imply if the page has next page */ L'e^D|
privateboolean hasNextPage; &/? Ct!_
l~rj7f;
/** the number of every page */ }_]AQN$'G
privateint everyPage; {h@\C|nF
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/** the total page number */ TwPQ8}pj?
privateint totalPage; jr4xh{Z`
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/** the number of current page */ JcR|{9ghT
privateint currentPage; xmv%O&0^}
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/** the begin index of the records by the current HU $"o6ap
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query */ CJ\a7=*i
privateint beginIndex; iYStl
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/** The default constructor */ v_!6S|
public Page(){ z%YNZ^d
B$_4ul\)
} ,x8;| o5
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/** construct the page by everyPage ep"[;$Eb
* @param everyPage J:m/s9r
* */ JXK\mah
public Page(int everyPage){ f8]sjeY
this.everyPage = everyPage; #{8IFA
} i)o;,~ee
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/** The whole constructor */ 'QCIKCn<
public Page(boolean hasPrePage, boolean hasNextPage, :5NMgR.d
Tn}`VW~
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int everyPage, int totalPage, 8)X9abC
int currentPage, int beginIndex){ c* {6T}VZr
this.hasPrePage = hasPrePage; r(>S
this.hasNextPage = hasNextPage; %bDxvaftT
this.everyPage = everyPage; MxsLrWxm
this.totalPage = totalPage; (F4e}hr&
this.currentPage = currentPage; xnY?<?J"!
this.beginIndex = beginIndex; $Z@*!B^
} k&dXK
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/** z'q~%1t
* @return Zhq_ pus"a
* Returns the beginIndex. $D^\[^S
*/
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publicint getBeginIndex(){ X.fVbePxUU
return beginIndex; n[3z_QI
} Qg*\aa94
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/** "6f`hy
* @param beginIndex +/ukS6>gr
* The beginIndex to set. M~:_^B
*/ +Q5O$8i
publicvoid setBeginIndex(int beginIndex){ *-T.xo
this.beginIndex = beginIndex; cE]z Tu?!
} b(*\4n
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/** Je6[q
* @return 2Vx4"fHP#N
* Returns the currentPage. A[Mke
*/ ~:a1ELqVw
publicint getCurrentPage(){ UM7@c7B?
return currentPage; {[H_Vl@
} / FcRp ,"
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/** {*yvvb
* @param currentPage U#3N90,N=
* The currentPage to set. 9-42A7g^C
*/ F9r.DG$}
publicvoid setCurrentPage(int currentPage){ }_D .Hy5
this.currentPage = currentPage; g*V.u]U!i
} (T%F^s5D
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/** o:d7IL
* @return a"vzC$Hxd
* Returns the everyPage. v)5;~.+%
*/ "V|Rq]_+%
publicint getEveryPage(){ V\L;EHtc$
return everyPage; jx}&%p X
} P<]U
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/** n7!T{+ge
* @param everyPage WPNB!"E98
* The everyPage to set. $J7V]c*-b
*/ ?2<)
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publicvoid setEveryPage(int everyPage){ E|@C:ghG
this.everyPage = everyPage; fd)8lK[KJ"
} {T4_Xn -I
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/** pv]@}+<Dt
* @return g NI1W@)
* Returns the hasNextPage.
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*/ zj`c%9N+
publicboolean getHasNextPage(){ ^#_gk uyd!
return hasNextPage; m%|\AZBA#
} ^z
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/** 4$Ai!a
* @param hasNextPage B{Cm`f8E
* The hasNextPage to set. R$:-~<O
*/ @@Q4{o
publicvoid setHasNextPage(boolean hasNextPage){ cC*WZ]
this.hasNextPage = hasNextPage; 7P{= Pv+
} 6r~9$IM
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/** w~]2c{\Qz
* @return P27Ot1px
* Returns the hasPrePage. ,HjJ jpE
*/ 3qWrSziD
publicboolean getHasPrePage(){ }i+C)VUX
return hasPrePage; {Ydhplg{
} lS=YnMs6a
=D(a~8&,
/** 6qZQ20h
* @param hasPrePage 392V\qtS
* The hasPrePage to set. 7?fgcb3
*/ zdP?HJ=F
publicvoid setHasPrePage(boolean hasPrePage){ e9p/y8gC
this.hasPrePage = hasPrePage; 534pX7dg
} 8{4'G$6
!@z9n\Yj
/** fk}Raej g
* @return Returns the totalPage. cj>@Jx}]M
* |.; N_i
*/ "@x(2(Y&
publicint getTotalPage(){ i;HXz`vT7
return totalPage; WyV4p
} r9f- [wC
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/** dX?j/M-
* @param totalPage G]B0LUT6c
* The totalPage to set. HS=w9:,
*/ 29Uqdo
publicvoid setTotalPage(int totalPage){ h%j4(v}r{C
this.totalPage = totalPage; BFNO yv
} ,88B@a
dz#"9i5b
} }cz58%
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wU%uO/sU9
IQBL;=.J.
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 :lu!%p<$
4f j}d.?
个PageUtil,负责对Page对象进行构造: orJ|Q3c)d
java代码: hTBJ\1
-
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/*Created on 2005-4-14*/ [)`*k#.=
package org.flyware.util.page; yK{P%oh)
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import org.apache.commons.logging.Log; {r&r^!K;
import org.apache.commons.logging.LogFactory; &wNr2PHd#
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/** za6 hyd^
* @author Joa R655@|RT
* R/{h4/+vJ
*/ .3EEi3z6z
publicclass PageUtil { 3g7]$}
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privatestaticfinal Log logger = LogFactory.getLog 2`i&6iz
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(PageUtil.class); #mH28UT
?3DL .U{
/** /8Lb_QH{
* Use the origin page to create a new page !UzE&CirV
* @param page ,vR>hyM
* @param totalRecords }ll&EB
* @return :{w3l O
*/ I>MLI=[Kg
publicstatic Page createPage(Page page, int r[E #JHw
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totalRecords){ Va[&~lA)
return createPage(page.getEveryPage(), 7gtaI3
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page.getCurrentPage(), totalRecords); &'\-M6GW
} @kd$.7Y9
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/** 2zo>`;l
* the basic page utils not including exception c%<81Y=
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handler ~,W|i
* @param everyPage tT`S"
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* @param currentPage a aVq>$G3
* @param totalRecords G>dXK,f<B0
* @return page m<Gd 6V5
*/ s#~VN;-I
publicstatic Page createPage(int everyPage, int &IQNsJL!e
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currentPage, int totalRecords){ B{#Fm6
everyPage = getEveryPage(everyPage); ^Oj^7.T+
currentPage = getCurrentPage(currentPage); 6heK8*.T
int beginIndex = getBeginIndex(everyPage, H(
LK}[
dnANlNMk?
currentPage); uvDOTRf
int totalPage = getTotalPage(everyPage, *o=Z~U9z
x>i =
totalRecords); T&dc)t`o
boolean hasNextPage = hasNextPage(currentPage, *`s*l+0b
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totalPage); @sR/l;
boolean hasPrePage = hasPrePage(currentPage); <MxA;A
}2=~7&)
returnnew Page(hasPrePage, hasNextPage, c7rC !v
everyPage, totalPage, +o.#']}Pl
currentPage, &~"N/o
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Id)
beginIndex); iR4"I7J
} TbqtT_{
='#7yVVcs
privatestaticint getEveryPage(int everyPage){ }m!T~XR</
return everyPage == 0 ? 10 : everyPage; * R&77 o7
} 5=s|uuw/
K/&
privatestaticint getCurrentPage(int currentPage){ Y(JZP\Tf_N
return currentPage == 0 ? 1 : currentPage; L#V e[
} G$`hPNSh
$9@Z\0
privatestaticint getBeginIndex(int everyPage, int lz).=N}m
*E@as
currentPage){ *eAt '
return(currentPage - 1) * everyPage; +5ql`C
}
X/!Y mV!
X?8bb! g%Q
privatestaticint getTotalPage(int everyPage, int (!ud"A|ab4
&WbHM)_n
totalRecords){ UuJ gB)
int totalPage = 0; Dhft[mvo
]VVx2ERs
if(totalRecords % everyPage == 0) iA2TvP#
totalPage = totalRecords / everyPage; ]:6IW:
else Kt#X'!9/<
totalPage = totalRecords / everyPage + 1 ; ,=6;dT
neWx-O
return totalPage; Dk~
JH9#
} t-FrF </0
\n0Gr\:
privatestaticboolean hasPrePage(int currentPage){ ZYl*-i&~?
return currentPage == 1 ? false : true; QswFISch
} uCFpH5>
'kCr1t
privatestaticboolean hasNextPage(int currentPage, K`R
R*"zLJP
int totalPage){ &'5j!
return currentPage == totalPage || totalPage == }e1]Ib!
Oi!uJofW
0 ? false : true; ^O5PcV 3Eg
} ()$tP3o
w3Qil[rg
n\scOM)3
} XQ k,xQ
B?XqH_=0L
^@maF<Jb
G{s
q|1
_'r&'s;<z
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。 xirZ.wj W
M-f; ,>
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 d_Y7/_i
5DeAH;
做法如下: mVyF M -`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _`]YWvh
/vPcg
的信息,和一个结果集List: ID=^497
java代码: WGMEZx
ADZU?7)
PwxRu
/*Created on 2005-6-13*/ "IdN *K
package com.adt.bo; 6c#1Do(W+
SQBe}FlktK
import java.util.List; 9r,7>#IF
X04JQLhy"
import org.flyware.util.page.Page; o7@81QA!e
i\k>2df
/** )6-!,D0 db
* @author Joa }W"/h)q
*/ ]OA8H[U-eA
publicclass Result { [RUYH5>Ik
uHO>FM,
private Page page; a^GJR]]
{
.\ces2,
private List content; @X>Oj .
jUX0sRDk
/** czp}-{4X
* The default constructor w`K=J!5y2g
*/ [Gb8o'
public Result(){ r`CsR0[
super(); w>gB&59r
} ~@Eu4ip)F
Hk|wO:7Be
/** Y]{~ogsn$:
* The constructor using fields |"EQyV
* 4] I7t
* @param page ??`zW
* @param content vqJjAls
*/ ;l=ZW
public Result(Page page, List content){ +(|
,Ke
this.page = page; w+3-j
this.content = content; v|u[BmA)*k
} m&8'O\$
^NiS7 )FX
/** niJtgK:H^
* @return Returns the content. Bgj^n{9x
*/ >FM2T<.;
publicList getContent(){ ;V\l,
u
return content; s8 0$
} ":N
EI
$4&e{fLt|v
/** Vu_QwWXO
* @return Returns the page. ;sn]Blpq
*/ S U$U
public Page getPage(){ 7gcJ.,Z.
return page; T4x%dg
} =L&}&pT
+>S\.h
s4
/** IX)\z
* @param content w0L+Sj db
* The content to set. .a`(?pPr,
*/ aqzIMOAf
public void setContent(List content){ aaM76;
this.content = content; 6#/v:;bF
} f+Ht
E;AOCbV*$
/** JQ)w/@Vu=
* @param page xF8^#J6>
* The page to set. 0'0GAh2
*/ I7q}<"`
publicvoid setPage(Page page){ tjTnFP/=
this.page = page; pw5uH
} %ryYa
} YRm6~c
}grel5lq
y)e8pPDG
]3iQpL
V*w~Sr%
2. 编写业务逻辑接口,并实现它(UserManager, G :JQ_w
Dq G m
UserManagerImpl) R9`37(c9+
java代码: ' (1`iQ;
iy\ 6e k1
.~t.B!rVSB
/*Created on 2005-7-15*/ {gwJ>]z"e
package com.adt.service; Xe7/
(Ld,<!eN0
import net.sf.hibernate.HibernateException; 0<C]9[l
&@h(6
import org.flyware.util.page.Page; QlCs,bT
aBonq]W
import com.adt.bo.Result; .>Fy ]Cqoh
r0fxEYze&
/** yO`HL'SMo
* @author Joa 85GU~.
*/ C=>IJ'G
publicinterface UserManager { [uD G;We=
5b5Hc Inu
public Result listUser(Page page)throws R
*uwp'@
TKBW2
HibernateException; 6A9
r{'1
$vK(Qm
} +XP9=U*g
2j
<Y>Y
;S.o`z1GI
|`,AAa
-.=:@H}r
java代码: E6zSMl5b
?6T\uzL +%
M\rZr3
/*Created on 2005-7-15*/ kt;uB
X3
package com.adt.service.impl; }a?( }{z-
X&14;lu%p
import java.util.List; y}bliN7;1e
O~
]3 .b
import net.sf.hibernate.HibernateException; y8arFG
y1c2(K>tu
import org.flyware.util.page.Page; +l) [A{
import org.flyware.util.page.PageUtil; -b`O"Ck*
d,d ohi
import com.adt.bo.Result; UHT2a9rG
import com.adt.dao.UserDAO; O=E?m=FR"
import com.adt.exception.ObjectNotFoundException; ,z0~VS:g 8
import com.adt.service.UserManager; 'YTSakNJ}
1@W*fVn
/** &=S<StH
* @author Joa s i=m5$V
*/ z<u*I@;
publicclass UserManagerImpl implements UserManager { Xdtyer%
EwX:^1f
private UserDAO userDAO; bD ADFitSo
J,Rp&tavt:
/** 0 F-db
* @param userDAO The userDAO to set. &6q67
*/ Rw!wfh_+
publicvoid setUserDAO(UserDAO userDAO){ I92orr1
this.userDAO = userDAO; &cHA xker
} F+Q(^Nk
thK4@C|X4
/* (non-Javadoc) fx3oA}
* @see com.adt.service.UserManager#listUser 3 =-XA2zJ
]r.95|V*
(org.flyware.util.page.Page) wMvAm%}+
*/ #)b0&wyW6i
public Result listUser(Page page)throws Pof]9qE-y
}LTy Xo
HibernateException, ObjectNotFoundException { z=1N}l~|*
int totalRecords = userDAO.getUserCount(); Zv&<r+<g
if(totalRecords == 0) Mv\]uAT`
throw new ObjectNotFoundException jWNF3\
KzWqHq
("userNotExist"); gO%oA} !i
page = PageUtil.createPage(page, totalRecords); #L`'<ge'g*
List users = userDAO.getUserByPage(page); P5Is#7udN8
returnnew Result(page, users); m4~>n(
} u #Y#,:{
dk>qTY+j5
} `*-rz<G
mGP&NOR0^y
>\4"k4d}
R8N*. [
Of.%rpgy
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 bBg=X}9
7Q>bJ Ek7
询,接下来编写UserDAO的代码: /:-Y7M*
3. UserDAO 和 UserDAOImpl: 1.IEs:(;
java代码: He)vl.
9gQ
]!Oq
T7#}&>
/*Created on 2005-7-15*/ ,%<ICusZ
package com.adt.dao; ZZ2vdy38
JS2h/Y$
import java.util.List; Zt/4|&w
m4x8W2q
import org.flyware.util.page.Page; iOXsj
hZwJ@ Vm#
import net.sf.hibernate.HibernateException; %R m`+
!cNw8"SIU
/** 1)v]<Ga~%1
* @author Joa B
x-"<^<
*/ zTS P8Q7
publicinterface UserDAO extends BaseDAO { hmp!|Q[)
:sA$LNj}
publicList getUserByName(String name)throws CXd/M~:!
P={8qln,X
HibernateException; vugGMP;D(
:F`"CR^,
publicint getUserCount()throws HibernateException; [oDu3Qn
*|Bt!
publicList getUserByPage(Page page)throws Ju"K"
Lpv,6#m`)
HibernateException; ')zf8>,
S'}pUGDO
} RH~I/4e
H7CWAQPfj
e+O502]
:R1F\FT*
J. $U_k
java代码: 2F#DJN#
1
.Nfl@]
>SHP,><H/
/*Created on 2005-7-15*/ -=4{X
R3
package com.adt.dao.impl; iCIU'yI
Ye]-RN/W
import java.util.List;
[yx8?5
%_.
fEFy07
import org.flyware.util.page.Page; nA#N ,^Rr
<`")Zxf+
import net.sf.hibernate.HibernateException; ]=vRjw
import net.sf.hibernate.Query; =58:e7(df
6rBP,\m
import com.adt.dao.UserDAO; 1<F6{?,z
ypLt6(1j%
/** d^qTY?k.
* @author Joa p(fL'
J
*/ Uu0
public class UserDAOImpl extends BaseDAOHibernateImpl t{Wu5<F:
)NmYgd~%
implements UserDAO { ;.{J>Q/U,
=-E%vnU
/* (non-Javadoc) jL,P )TC
* @see com.adt.dao.UserDAO#getUserByName sUz,F8G
<%"o-xZq7C
(java.lang.String) cP^c}e*;NS
*/ N7UGgn=
publicList getUserByName(String name)throws QC<O=<$Q[
C Xh>'K
HibernateException { w`X0^<Fv
String querySentence = "FROM user in class o:PdPuZVR
"5@\"L
com.adt.po.User WHERE user.name=:name"; se*!OiOt
Query query = getSession().createQuery 2Dw}o;1'
X}ft7;Jpy
(querySentence); D9%t67s
query.setParameter("name", name); )QW
p[bV
return query.list(); ZmAo9>'Kg
} @ n^2UJ
tQ,3nI!|xF
/* (non-Javadoc) gt\*9P
* @see com.adt.dao.UserDAO#getUserCount() tvcM<
e20
*/ D]?yGI_
publicint getUserCount()throws HibernateException { F*p@hl
int count = 0; mWTV)z57
String querySentence = "SELECT count(*) FROM dmPAPCm%y
s|D[_N!|
user in class com.adt.po.User"; &Ivf!Bgm{Z
Query query = getSession().createQuery -+fW/Uo
k{J\)z
(querySentence); pcNpr`
count = ((Integer)query.iterate().next JQDS3v=1$
z-JYzxL9
()).intValue(); 'J8Ga<s7C
return count; n8Rsle`a
} =y0h\<[
M.``o1b
/* (non-Javadoc) $fAZ^
* @see com.adt.dao.UserDAO#getUserByPage ?X@uR5?{
@dc4v_9
(org.flyware.util.page.Page) {r?+PQQ#
*/ L0>7v
publicList getUserByPage(Page page)throws WZN0`Od
e]@
B61lc
HibernateException { ^_t7{z%sA[
String querySentence = "FROM user in class jIjW +D`
+[7 DRT:
com.adt.po.User"; K>_~|ZN1C8
Query query = getSession().createQuery TJUYd9O4[
PQXCT|iJ
(querySentence); an)Z.x
query.setFirstResult(page.getBeginIndex()) `<(o;*&Gd
.setMaxResults(page.getEveryPage()); lyw)4;wt\
return query.list(); gg@Ew4L&
} I[KAW"
eE" *c>I
} 2`A\'SM'4
AA5UOg\jI
Bpp(5
WDF6.i ?
]F
srk
至此,一个完整的分页程序完成。前台的只需要调用 Q*8efzgs|
Ws:+P~8
userManager.listUser(page)即可得到一个Page对象和结果集对象 7T?T0x3>
MCTTm^8O
的综合体,而传入的参数page对象则可以由前台传入,如果用 >:|jds#
7~H"m/;U&
webwork,甚至可以直接在配置文件中指定。 a0PClbf2.
8gW$\
下面给出一个webwork调用示例: JfzfxfM
java代码: K~A@>~vFb
%<\tN^rP
Id{Ix(O
/*Created on 2005-6-17*/ ~;@\9oPpz%
package com.adt.action.user; yAQ)/u[|
G$t:#2
import java.util.List; R<Ct{f!
vu3zZMl
import org.apache.commons.logging.Log; emG1Wyl
import org.apache.commons.logging.LogFactory; o$Z]qhq
import org.flyware.util.page.Page; O
+Xu?W]
|`O210B@
import com.adt.bo.Result; EO\- J-nM
import com.adt.service.UserService; Thuwme
import com.opensymphony.xwork.Action; Ur(< ]
%8lWJwb7u
/** 6A-nhvDP
* @author Joa QxiAC>%K
*/ t]+h.
publicclass ListUser implementsAction{ vlPViHF.
'h>CgR^NM1
privatestaticfinal Log logger = LogFactory.getLog 41c4Xj?'
cD9.L
(ListUser.class); +GT"n$)+
?S'Wd=
private UserService userService; .x_F4 #Ka
?-=<7
~$
private Page page; %)=c#H1
KA
elq*
privateList users; VujIKc#4
m">2XGCn
/* i)@H
* (non-Javadoc) vgN%vw pL
* ]QKKtvN
* @see com.opensymphony.xwork.Action#execute() ^`f qK4<
*/ ~\u?Nf~L
publicString execute()throwsException{ s$xm
Result result = userService.listUser(page); Ex5LhRe>=
page = result.getPage(); CzI/Z+\
users = result.getContent(); 1(qL),F;
return SUCCESS; ap[Q'=A`
} >Dq&[9,8
~X,ZZ 9H
/** Ki\J)l
* @return Returns the page. p*~b5'+ C+
*/ N2&h yM
public Page getPage(){ y~<_ux,
return page; oEsqLh9a|
} GE}>{x=^x
Z;cA_}5
/** trlZ
* @return Returns the users. P.kf|,8L
*/ `FAZAC\
publicList getUsers(){ y>&
s;
return users; iM~qSRb#mJ
} #yOn /
f&?
8fB8{
/** Gy!bPVe
* @param page h/7_I uD
* The page to set. a4eE/1
*/ )
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publicvoid setPage(Page page){ _nec6=S6(
this.page = page;
Qo+Y
} wcW}Sv[r
]
jycg@=B
/** vzZ"TSP
* @param users qwYq9A$+
* The users to set. =6[R,{|C
*/ <Gz* 2i
publicvoid setUsers(List users){ K&;/hdS=F
this.users = users; F`57;)F
} I GB)
RT"JAJTi/
/** $#FA/+<&$
* @param userService Cd7l+~*Y
* The userService to set. 1_z~<d
@?;
*/ aV G4Df
publicvoid setUserService(UserService userService){ Y{2L[5_1
this.userService = userService; %
r0AhWv
} Hf9F:yH
} zJG=9C?
5>&C.+A 9
}c'T]h\S
zX&wfE8T
8:jakOeT
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, bP{uZnOM2P
)<_:%oB
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>-u9%aa
W"1=K]B
么只需要: !6eF8T
java代码: KHoDD=O
"@rXN"4
m=%yZ2F;
<?xml version="1.0"?> mh8)yy5\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;b^"b{
FyA0"
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
!}L
cJ
}?[a>.]u
1.0.dtd"> (BY5omlh
o<!tNOH
<xwork> ]Yt,|CPe2
N|asr,
<package name="user" extends="webwork- Hw~?%g:<S
g
I4Rku
interceptors"> ]SNcL[U
=B"^#n ;
<!-- The default interceptor stack name rF=\H3`p3
Hq "l`
--> YI),yj
<default-interceptor-ref #80M+m
nfS.0\z
name="myDefaultWebStack"/> K7]QgfpSZ
+P;&/z8i*g
<action name="listUser" DQ= /Jr~
Z1oUAzpj4
class="com.adt.action.user.ListUser"> +D|E8sz8
<param -h{| u{t
>:f&@vwm
name="page.everyPage">10</param> jU=n\o=?
<result aaFt=7(K
$Zf]1?|xa
name="success">/user/user_list.jsp</result> $mF9os-
</action> QP!0I01
E,7b=t
</package> cGS7s 8U
"i;"
</xwork> a f UOIM
U
)J/so)
l6< bV#_qe
h|[oQ8)
@tPptB
d 8M8O3
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 oVeC@[U
p/'09FY+ U
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Ll0"<G2t
l&uBEYx
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N_f>5uv
9NausE40
gtRs||
z#\YA]1
]xN)>A2
我写的一个用于分页的类,用了泛型了,hoho GaLQ/V2R
0 LIRi%N5*
java代码: S/x CX!
Mt%=z9OLq9
lAo S 9w
package com.intokr.util; ++Fk8R/$U[
nx@h
import java.util.List; p]J0A ^VV
?eri6D,86w
/** Iz[wrtDI1
* 用于分页的类<br> bSS=<G9
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +X!QH/ 8
* _Wgpk0
* @version 0.01 Bngvm9k3
* @author cheng lIgAc!q(
*/ eX <@qa4<
public class Paginator<E> { lH%-#2]
privateint count = 0; // 总记录数 OjfumZL#
privateint p = 1; // 页编号
03a<Cd/S
privateint num = 20; // 每页的记录数 z*G(AcS)
privateList<E> results = null; // 结果 v_NL2eQ~
#lO~n.+P
/** z;6,,
* 结果总数 vlh$NK+F
*/ m-XS_5x\
publicint getCount(){ Vv3:x1S
return count; =;y(b~
} xaW9Sj0ZM
X"O^4MnvI
publicvoid setCount(int count){ Q7XlFjzcm
this.count = count; {V5eHn9/Q'
} <,I]=+A
s:Io5C(
/** J|:Zs1.<d
* 本结果所在的页码,从1开始 < <]uniZ\
* +l(lpp>,
* @return Returns the pageNo. )A:|8m
*/ *e
*V%w~75
publicint getP(){ _q3|Ddm2LN
return p; SB=%(]S
} =JfSg'7
Vl%jpjqP
/** (v1~p3H
* if(p<=0) p=1 oO][X
* (bON[6OGm
* @param p x`VA3nE9
*/ IHvrx:7
publicvoid setP(int p){ CyD)=e{
if(p <= 0) X!!3>`|
p = 1; fm&pxQjg
this.p = p; 6>j0geFyE2
} to#N>VfD
fE,Io3
/** FFpG>+*3
* 每页记录数量 Jj,fdP#\
*/ hvOl9W>
publicint getNum(){ I#9q^,,F
return num; *W$bhC'w
} NAh^2X
ZCz#B2Sf8
/** _Sn45h@"
* if(num<1) num=1 &@/25Y2
*/ WC`x^HI
publicvoid setNum(int num){ :XeRc"m<
if(num < 1) Tb<}GcwJ
num = 1; w ^8i!jCy
this.num = num; L}\~)
} jC_m0Iwc
c@/K}
/** g<PglRr"
* 获得总页数 m+9~f_}
*/ s|d"2w6t
publicint getPageNum(){ Qs7*_=+h
return(count - 1) / num + 1; x5%x""VEK
} G'f5MP1
C}Ucyzfr,p
/** .+$ox-EK8
* 获得本页的开始编号,为 (p-1)*num+1 H/N4tWk"
*/ 5:|=/X%#qp
publicint getStart(){ ~9DD=5\
return(p - 1) * num + 1; JpC_au7CX
} 6"<q{K
@tg4rl
/** f&NXWo/
* @return Returns the results.
B`wrr8"Rz
*/ 0=Mu|G|Z
publicList<E> getResults(){ _FtsO<p)"
return results; QI*<MF,1
} 6gTc)rhRT
nD\H$5>5
public void setResults(List<E> results){ ky=h7#wdv-
this.results = results; xvTz|Y
} h"t\x}8qq
NGVl/Qd
public String toString(){ VQl(5\6O
StringBuilder buff = new StringBuilder ,'&H`h54
JUdQ Q
(); #VynADPs`o
buff.append("{"); /nB|Fo_&Q
buff.append("count:").append(count); _BHEK
buff.append(",p:").append(p); 'e:(61_
buff.append(",nump:").append(num); e]-%P(}Z
buff.append(",results:").append oUx%ra{
0Ait7`
(results); M*2
Nq=3
buff.append("}"); ciGJtD&P
return buff.toString(); s"B+),Jod
} )%vnl~i!
e"&QQ-q
} njckPpyb@
M$U Zn
OU'm0Jlk