Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #we>75l{+R
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +xfW`[.{
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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 M+;P?|a
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 @GQ8q]N:<
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分页支持类: UIOEkQ\Wl
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java代码: BwJ^_:(p~
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package com.javaeye.common.util; u:$x6/t
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import java.util.List; 96pk[5lj{?
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publicclass PaginationSupport { q|o|/ O-{
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; Ah>gC!F^
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privateList items; Sf&?3a+f
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privateint totalCount; QW~5+c9JJ
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privateint[] indexes = newint[0]; g[s\~MF@s
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privateint startIndex = 0; *SkiFEoD
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public PaginationSupport(List items, int |Vwc/9`t]>
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totalCount){ +K;Y+
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setPageSize(PAGESIZE); X#DL/#z k
setTotalCount(totalCount); ')5L_$
setItems(items); J4G> E.8
setStartIndex(0); px_s@>l`
} [.;%\>Qk<
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public PaginationSupport(List items, int N(:nF5>_
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totalCount, int startIndex){ H+VO.s.a
setPageSize(PAGESIZE); _7lt(f[S
setTotalCount(totalCount); HX3D*2v":
setItems(items); ],\sRQbv&
setStartIndex(startIndex); IAP/G5'Q
} C[xJU6z
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public PaginationSupport(List items, int [O7w =
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totalCount, int pageSize, int startIndex){ 1Sg|3T8bGT
setPageSize(pageSize); f4'El2>-86
setTotalCount(totalCount); v`S2M
setItems(items); }A1|jY)x
setStartIndex(startIndex); *#lBQBH|.
} @%OPy|=,{
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publicList getItems(){ "mPSA Z
return items; mPs%ZC
} m!5HRjOO
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publicvoid setItems(List items){ 7`IUMYl#~
this.items = items; cgs3qI
} -,QKTxwo>
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publicint getPageSize(){ ;Y'8:ncDn
return pageSize; 6|
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} d"B@c;dD
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publicvoid setPageSize(int pageSize){ s~=KhP~
this.pageSize = pageSize; qr)v'aC3
} <.,RBo
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publicint getTotalCount(){ 4>4V-m\
return totalCount; ;w`sz.
} *A?8F"6>
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publicvoid setTotalCount(int totalCount){ 9ZDVy7m\i-
if(totalCount > 0){ WI1T?.Gc
this.totalCount = totalCount; :7p9t.R<$h
int count = totalCount / UrO=!G k
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pageSize; bz{^ h'
if(totalCount % pageSize > 0) #V.ZdLo(
count++; PXw|
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indexes = newint[count]; [ rQMD^:M$
for(int i = 0; i < count; i++){ }#yU'#|d
indexes = pageSize * C=N!z
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i; "^;#f+0
} HLjvKE=W
}else{ $!!R:Wn/R
this.totalCount = 0; wgY6D!Y
} (VgNb&Yo9
} tg~A}1o`0
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publicint[] getIndexes(){ j~Q}F |i8
return indexes; VmN}FMGN
} DH5bpg&T
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publicvoid setIndexes(int[] indexes){ 8y$5oD6g9
this.indexes = indexes; vqq6B/r@Fu
} ,-@xq.D
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publicint getStartIndex(){ bqSMDK
return startIndex; h`=r)D
} oZgHSR RL
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publicvoid setStartIndex(int startIndex){ ,09DBxQq,
if(totalCount <= 0) wGg0hL
this.startIndex = 0; }FrEF\}]_7
elseif(startIndex >= totalCount) '%R<"
this.startIndex = indexes ~gP7s_qr{
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[indexes.length - 1]; yahAD.Xuo@
elseif(startIndex < 0) R.K?
this.startIndex = 0; Hi^35
else{ *oCxof9JA
this.startIndex = indexes _B)s=Snx
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[startIndex / pageSize]; hjkLVL
} dUIqD l
} 8qn 9|
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publicint getNextIndex(){ Us'Cs+5XcG
int nextIndex = getStartIndex() + 4S tjj!ew
0; 7#ji
pageSize; `|nH1sHFq
if(nextIndex >= totalCount) nE_Cuc>K\
return getStartIndex(); yq?]V7~
else kd yAl,
return nextIndex; Tr~sieL
} rWA6XDM7
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publicint getPreviousIndex(){ 42&v% ;R
int previousIndex = getStartIndex() - kVd5,Qd
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pageSize; `?l3Ct*
if(previousIndex < 0) 6D|p Qs
return0; /hL\,x2
else g0PT8]8
return previousIndex; Xx_tpC?
} Qlw>+y-i
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} Lbcy:E*g
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抽象业务类 Goxl3LS<
java代码: U9
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/** z`4c 4h]I
* Created on 2005-7-12 eTT)P
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package com.javaeye.common.business; Fk{J@Y
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import java.io.Serializable; nob0T5G
import java.util.List; M ,`w A
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import org.hibernate.Criteria; ?E6^!4=,
import org.hibernate.HibernateException; +1QK}H~
import org.hibernate.Session; /&r|ec5
import org.hibernate.criterion.DetachedCriteria; +"dv7
import org.hibernate.criterion.Projections; KFU%DU G
import TkRmV6'w
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org.springframework.orm.hibernate3.HibernateCallback; "oR@JbdX
import \9`#]#1bx5
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org.springframework.orm.hibernate3.support.HibernateDaoS 7/aOsW"6
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upport; H]&gW/=
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import com.javaeye.common.util.PaginationSupport; E$A3|rjnoN
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public abstract class AbstractManager extends /`3#4=5-
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HibernateDaoSupport { iG#}`
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privateboolean cacheQueries = false; i7 w(S3a
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privateString queryCacheRegion; 2}vNSQvG
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publicvoid setCacheQueries(boolean 1y(UgEg
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cacheQueries){ Z+4D.bA
this.cacheQueries = cacheQueries; T7[NcZ:I
} WF[bO7:
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publicvoid setQueryCacheRegion(String jo9gCP.
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queryCacheRegion){ >P=Q #;v
this.queryCacheRegion = rzUlO5?R=
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queryCacheRegion; Yf}xwpuLk
} *z8|P#@
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publicvoid save(finalObject entity){ D=+NxR[
getHibernateTemplate().save(entity); ,eRQu.
} nL-K)G,
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publicvoid persist(finalObject entity){ @1:0h9%
getHibernateTemplate().save(entity); Z6Fp\aI8@
} ok{!+VCB5
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publicvoid update(finalObject entity){ M'L;N!1A
getHibernateTemplate().update(entity); ++jAz<46
} 4<gb36)|4
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publicvoid delete(finalObject entity){ =r9r~SR#
getHibernateTemplate().delete(entity); KC#/Z2A|<
} c{Ou^.yR
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publicObject load(finalClass entity, ba@ctkCW
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finalSerializable id){ {A:j[
return getHibernateTemplate().load :J/M,3
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(entity, id); =0
} ~ G6"3"
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publicObject get(finalClass entity, +&i +Mpb
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finalSerializable id){ <hx+wrv
return getHibernateTemplate().get t0)<$At6J
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(entity, id); 2%u;$pj
} qfoD
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publicList findAll(finalClass entity){ F?-R$<Cn2~
return getHibernateTemplate().find("from n, i'Dhzk
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" + entity.getName()); =
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} ~j9O$s~)
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publicList findByNamedQuery(finalString O"G >wv
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namedQuery){ r^,<(pbd
return getHibernateTemplate x[3A+
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().findByNamedQuery(namedQuery); cV{o?3<:B
} F4L;BjnJ
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publicList findByNamedQuery(finalString query, x1&W^~
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finalObject parameter){ pmWr]G3,*
return getHibernateTemplate Av' GB
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().findByNamedQuery(query, parameter); G 2!xPHz
} fw6UhG
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publicList findByNamedQuery(finalString query, Q[F}r`
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finalObject[] parameters){ re?s.djT
return getHibernateTemplate ~{,X3-S_H
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().findByNamedQuery(query, parameters); y:m_tv0~0
} e]=lKxFh&l
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publicList find(finalString query){ :j }fC8'
return getHibernateTemplate().find zOgTQs"ZH
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(query); uvP2Wgt
} YjOs}TD lx
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publicList find(finalString query, finalObject )B,|@ynu
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parameter){ \^7C0R-hX
return getHibernateTemplate().find OyV<u@[i
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(query, parameter); ~vlype3/EF
} U8qtwA9t
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public PaginationSupport findPageByCriteria JM1R ;i6
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(final DetachedCriteria detachedCriteria){ GaX[C<Wt
return findPageByCriteria g<{xC_J
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &nBa=Enf
} J]f3CU,<N
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public PaginationSupport findPageByCriteria _4^R9Bt
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(final DetachedCriteria detachedCriteria, finalint ^P151*=D
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startIndex){ 2{|h8oz
return findPageByCriteria 4jD2FFG-
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jReXyRmo({
(detachedCriteria, PaginationSupport.PAGESIZE, ,|&9M^
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startIndex); .{y
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} y ]?V~%
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public PaginationSupport findPageByCriteria [1.+HyJ}
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(final DetachedCriteria detachedCriteria, finalint vWGwVH/K
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pageSize, gz3pX#S
finalint startIndex){ +\v?d&.f0
return(PaginationSupport) \7CGUB>L
As>_J=8} 3
getHibernateTemplate().execute(new HibernateCallback(){ b0oMs=uBn
publicObject doInHibernate _a1x\,R|DB
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(Session session)throws HibernateException { =UV`.d2[
Criteria criteria = 9-MUX^?u
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detachedCriteria.getExecutableCriteria(session); TqnTS0fx
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount 1YH+d0UGn
'3g[]M@M
()).uniqueResult()).intValue(); rW=Z>1
criteria.setProjection lv04g} W
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(null);
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List items = t2)rUWg
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criteria.setFirstResult(startIndex).setMaxResults ~;N^g4s
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(pageSize).list(); :\|SQKD
PaginationSupport ps = 9E6_]8rl
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=
new PaginationSupport(items, totalCount, pageSize, Ig
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startIndex); P}4QQw
return ps; .4E&/w+
} .nVa[B|.
}, true); BBev<
} ?U2<
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public List findAllByCriteria(final a*&B`77`|
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DetachedCriteria detachedCriteria){ sr{a(4*\
return(List) getHibernateTemplate 6}!#;@D~
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().execute(new HibernateCallback(){ rogT~G}q
publicObject doInHibernate Rx}$0c0
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(Session session)throws HibernateException { ~GZY 5HF
Criteria criteria = ):[7E(F=
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detachedCriteria.getExecutableCriteria(session); :0Rx#%u}#
return criteria.list(); E4M@WNPx
} t&AFUt\c
}, true); V T\F]Oa#
} o%IA}e7PAa
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public int getCountByCriteria(final )!P)U(*v
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DetachedCriteria detachedCriteria){ T[g[&K1Y
Integer count = (Integer) 5?]hd*8
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getHibernateTemplate().execute(new HibernateCallback(){ f,kZ\Ia'r
publicObject doInHibernate ']2E {V
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(Session session)throws HibernateException { ]7Tkkw$
Criteria criteria = YTUZoW2
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detachedCriteria.getExecutableCriteria(session); =4FXBPoQK
return ;wz^gdh;
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criteria.setProjection(Projections.rowCount ww],y@da
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()).uniqueResult(); +%ee8|\
} |#]@Z)xa
}, true); h4T5+~rw
return count.intValue(); lPw%ErG
} u>2
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} 3h$6t7=C
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用户在web层构造查询条件detachedCriteria,和可选的 LG9+y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {>hC~L?6
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PaginationSupport的实例ps。 fSK]|"c
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ps.getItems()得到已分页好的结果集 ;$.J3!
ps.getIndexes()得到分页索引的数组 Egg=yF>T
ps.getTotalCount()得到总结果数 X= 5xh
ps.getStartIndex()当前分页索引 u)}$~E>
ps.getNextIndex()下一页索引 }fb#G<3
ps.getPreviousIndex()上一页索引 K,+LG7ec
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _>(^tCo
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 QbkLdM,S*
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一下代码重构了。 "{@A5A
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我把原本我的做法也提供出来供大家讨论吧: 47+&L
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首先,为了实现分页查询,我封装了一个Page类: IzikDc10
java代码: )dbB=OZ
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/*Created on 2005-4-14*/ hYPl&^
package org.flyware.util.page; I*{4rDt
+ jc!5i .
/** \2N!:%k
* @author Joa 2@'oe7E
* TC!Yb_H}gN
*/ U>=Z-
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publicclass Page { >s>1[W @*
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/** imply if the page has previous page */ :61Tun
privateboolean hasPrePage; EMwS1~3dD
_=_Px@<Q
/** imply if the page has next page */ ,k )w6)
privateboolean hasNextPage; U}yW<#$+
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/** the number of every page */ 5na~@-9p
privateint everyPage; Uc7mOa}4
@XLy7_}
/** the total page number */ xST8|H
privateint totalPage; 5D\f8L
?pr9f5
/** the number of current page */ IUE~_7
privateint currentPage; j9eTCJqB
-+(jq>t
/** the begin index of the records by the current [#-b8Cu
@L<*9sLWh
query */ D!{Y$;
privateint beginIndex; "& ])lz[u
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/** The default constructor */ _4"mAPt
public Page(){ }Lc-7[/
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} Wk~WOzr}^
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/** construct the page by everyPage _ky,;9G]
* @param everyPage >80;8\
* */ HW3 }uP\c
public Page(int everyPage){
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this.everyPage = everyPage; d4u})
} t2/#&J]
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/** The whole constructor */ Yw4n-0g
public Page(boolean hasPrePage, boolean hasNextPage, $ 7O}S.x
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int everyPage, int totalPage, e<3K;Q
int currentPage, int beginIndex){ aC$B2
this.hasPrePage = hasPrePage; aZ2!i
this.hasNextPage = hasNextPage; ]NUl9t*N4
this.everyPage = everyPage; JlH&??
this.totalPage = totalPage; K(q+
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this.currentPage = currentPage; 15%w 8u
this.beginIndex = beginIndex; '8Q]C*Z
} xbdN0MAU
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/** iq8GrdL"
* @return {IxA)v-`
* Returns the beginIndex. AqWUwK9T
*/ v*'^r)Q[p
publicint getBeginIndex(){ i!J8 d"
return beginIndex; S=5<^o^h3
} OVm\
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/** AJh w
* @param beginIndex 1n=lqn/
* The beginIndex to set. &~8oQC-eF
*/ N >FKy'.gk
publicvoid setBeginIndex(int beginIndex){ !TAlBkj
this.beginIndex = beginIndex; sF|5XjQ
} ;XF:\<+
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/** \n$u)Xj~6^
* @return h]Wr [v
* Returns the currentPage. 4lr(,nPRD
*/ n"c)m%yZ
publicint getCurrentPage(){ H\h3TdL
return currentPage; $w)!3c4
} J2::'Hw*s
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/** k3u"A_"c
* @param currentPage G0/4JSH
* The currentPage to set. M$y+q
^
*/ FG%X~L<d,)
publicvoid setCurrentPage(int currentPage){ ?ATOXy
this.currentPage = currentPage; W}m)cn3@
} Lhl]g^SN
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/** 0+?7EL~
* @return h}*/Ge]aM
* Returns the everyPage. /j4P9y^]=
*/ ".W8)
publicint getEveryPage(){ <vUbv
return everyPage; Z3#P,y9@
} KV}FZ3jY
qs1 ?IYD
/** 4A8;tU$&
* @param everyPage ?%O(mC]u&
* The everyPage to set. syWG'(>
*/ O#F
publicvoid setEveryPage(int everyPage){ Q9~*<I> h;
this.everyPage = everyPage; =:&ly'QB&
} GNgKo]u
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/** 4.Q} 1%ZN
* @return a2dnbfSWa[
* Returns the hasNextPage. )[PtaPWeT
*/ =8t]\Y?
publicboolean getHasNextPage(){ +aJ>rR
return hasNextPage; "]"|"0#i
} |bq$xp
v9:9E|,U+
/** le1}0L
* @param hasNextPage C69q&S,
* The hasNextPage to set. HW=C),*]cR
*/ P#RR9>Q
publicvoid setHasNextPage(boolean hasNextPage){ ^Y@\1fX 4e
this.hasNextPage = hasNextPage; SLkhCR
} VRI0W`
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/** [Grxw[(_:
* @return T+*%?2>q"
* Returns the hasPrePage. 6%t1b M
a
*/ o<[#0T^K
publicboolean getHasPrePage(){ |_] Q$q[[%
return hasPrePage; H=g`hF]`
} G+%zn|
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/** pk^K:Xs}
* @param hasPrePage ;g @4|Ro
* The hasPrePage to set. T?x[C4wf+
*/ 8dO!
publicvoid setHasPrePage(boolean hasPrePage){ =-8bsV/l
this.hasPrePage = hasPrePage; YpH&<$x:
} S'4(0j
rf?qdd(~cH
/** yUZb#%n
* @return Returns the totalPage. O!P H&;H
* y`F3Hr c
*/ :<hXH^n
publicint getTotalPage(){ F@mQQ
return totalPage; r~/
} rf>0H^r
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/** _J Hd9)[
* @param totalPage VtnRgdJ
* The totalPage to set. `+o2DA)#(
*/ )Qe~8u@?
publicvoid setTotalPage(int totalPage){ ;nodjbr,j
this.totalPage = totalPage; tKuVQH~D
} ToJ$A`_!`
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} (BTVD,G
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[<%H>S1
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 >Db;yC&
Ov-icDMm
个PageUtil,负责对Page对象进行构造: MCS8y+QK
java代码: ;D:9+E<>a
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/*Created on 2005-4-14*/ vR s,zL$W
package org.flyware.util.page; .#rJ+.2
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import org.apache.commons.logging.Log; 7JEbH?lEN
import org.apache.commons.logging.LogFactory; wgamshm"d
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/** )XvilCk1
* @author Joa ) L#i%)+
* !a7[8&
*/ l038%U~U!
publicclass PageUtil { h| ,:e;>}
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privatestaticfinal Log logger = LogFactory.getLog P(+&OoY2
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(PageUtil.class); n?- })
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/** &Xf^Iu
* Use the origin page to create a new page 3BtaH#ZY
* @param page bn!HUM,
* @param totalRecords l|kSsP:GO
* @return FFu9&8Y
*/ d-k%{eBV
publicstatic Page createPage(Page page, int {]:7bV#JP
U)E(`{p]
totalRecords){ >8k_n
return createPage(page.getEveryPage(), qU#1i:(F*
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page.getCurrentPage(), totalRecords); Q36qIq_0e
} V:VO[e<e
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/** n ~shK<!C
* the basic page utils not including exception aqj@Cjk4Z
gk"$,\DI
handler c_vqL$Dl
* @param everyPage cc~O&?)i
* @param currentPage )N7Y^CN~
* @param totalRecords 4\Tl\SZ?
* @return page P} 0%-JC
*/ v":x4!kdX
publicstatic Page createPage(int everyPage, int M<kj_.
BT}!W`
currentPage, int totalRecords){ {(r`k;fB
everyPage = getEveryPage(everyPage); 6)Y.7 XR
currentPage = getCurrentPage(currentPage); X]wRwG
int beginIndex = getBeginIndex(everyPage, 3'cE\u
]pH-2_
currentPage); 23Nw!6S
int totalPage = getTotalPage(everyPage, ;\14b?TUH
LUM@#3&
totalRecords); 0{,Z{&E
boolean hasNextPage = hasNextPage(currentPage, u~WVGjoQ
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totalPage); Hn5|B 3vN
boolean hasPrePage = hasPrePage(currentPage); @d
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returnnew Page(hasPrePage, hasNextPage, _j< K=){
everyPage, totalPage, G
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currentPage, l'/R&`-n
;/r1}tl+3>
beginIndex); xKuRh}^K
} tt0f-:#
@zU6t|mhz
privatestaticint getEveryPage(int everyPage){ .J)I | '
return everyPage == 0 ? 10 : everyPage; 6W]9$n\"?
} ABD)}n=%c
e?JW
privatestaticint getCurrentPage(int currentPage){ NbgK@eV}+{
return currentPage == 0 ? 1 : currentPage; i{`FmrPO~
} $a
]_w.@
JM x>][xD
privatestaticint getBeginIndex(int everyPage, int pe] A5\4c
60J;sGW
currentPage){ G9xmmc
return(currentPage - 1) * everyPage; :6vm+5!
} 4^WpS/#4
E\as@pqo\p
privatestaticint getTotalPage(int everyPage, int mOy^vMa
^c^#dpn
totalRecords){ >8WP0Qx/
int totalPage = 0; IC1NKn<k
!g5xq
if(totalRecords % everyPage == 0) "alyfyBu'M
totalPage = totalRecords / everyPage; a
yCY~=i
else ?[g=F <r
totalPage = totalRecords / everyPage + 1 ; "Zl5<
fI{&#~f4C
return totalPage; [5G6VNh=
} 6p?,(
5nT"rA
privatestaticboolean hasPrePage(int currentPage){ jbVECi-
return currentPage == 1 ? false : true; 9Uj$K>:
} &PYK8}pBk3
3I)VHMC
privatestaticboolean hasNextPage(int currentPage, D~hg$XzK
6kpg+{;
int totalPage){ * w?N{.
return currentPage == totalPage || totalPage == kYG/@7f/
QPx_-
0 ? false : true; gtk7)Uh
} x=b7': nQ
tzZ`2pSh
&O9 |#YUq
} )Im#dVQs=
bM {s
T"
0ZZZoPo
%E#s\B,w
_ba>19csq%
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。 #gz
M|
M+U9R@
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 [@J/eWB
X-6de>=
做法如下: $c0h.t
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ok!L.ac
'*5i)^
的信息,和一个结果集List: _F>CBG
java代码: \fG#7_wt
YB(Q\hT~\;
p1Jh0o8
/*Created on 2005-6-13*/ Jm xH"7hTE
package com.adt.bo; j(m.$:
9^oKtkoDZ
import java.util.List; yXSFjcoB
=/s>Q l
import org.flyware.util.page.Page; l`oZ)?ur
)bS yB29S
/** ~Sj9GxTe
* @author Joa sDPs
G5q<
*/ |TS>hwkI
publicclass Result { AL9chYP}/
~;l@|7wGz
private Page page; ED=V8';D
XGYbnZ~
private List content; h2Ld[xvCu%
)J2mM
/**
gbF+WE
* The default constructor ?}wk.gt>
*/ #M9~L[nFS
public Result(){ "I3@m%qv
super(); $"+djI?E9
} B3We|oe !
rDm~h~u5
/** 1oR7iD^
* The constructor using fields Zq+v6fk_Mn
* >3p\m
* @param page S\:P-&dC
* @param content ZP@
$Q%up
*/ >0/i[k-dk
public Result(Page page, List content){ q!.byrod
this.page = page; )
i;1*jK
this.content = content; (SpX w,:
} +"rDT1^V
zQcL|(N
/** r)y=lAyF>
* @return Returns the content. bo2H]PL*
*/ J\+0[~~
publicList getContent(){ B^4&-z2|
return content; E{XH?_xo
} kZR8a(4D
'GNK "XA^
/** +ieY:H[
* @return Returns the page. @:+8?qcP
*/ 6n,i0W
public Page getPage(){ |:nn>E}ZA/
return page; ff]6aR/
UQ
} Vr]id
8<X#f
!
/** ")SFi^]
* @param content r+A{JHnN
* The content to set. |,S+@"0#
*/ a!a-b~#cx
public void setContent(List content){ T-.%
this.content = content; }tRm] w
} 2L3)#22m*
/5S30 |K
/** sd*p/Q|4
* @param page h
k]
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* The page to set. 6.sx?Y YM
*/ CSJdvxb
publicvoid setPage(Page page){ =$u!
59_dE
this.page = page; joFm]3$;
} ,f~J`3(&
} qB5j;@r
gqZ'$7So
y&6FybIz
`95r0t0hh\
(l\1n;s*B
2. 编写业务逻辑接口,并实现它(UserManager, !\-{D$E?H
+9M^7/}H
UserManagerImpl) :0Bq^G"ge
java代码: \HqNAE2T
t)~"4]{*}D
@@R7p
/*Created on 2005-7-15*/ ,BH@j%Jmy
package com.adt.service; BBaQ}{F8>2
APvDP?
import net.sf.hibernate.HibernateException; W<bGDh
@P#N2:jwj
import org.flyware.util.page.Page; '}9x\3E
hpHr\g
import com.adt.bo.Result; #*D)Q/k
|t^E~HLm,
/** 1a?!@g)
* @author Joa O9G[j=U
*/ }u\])I3
publicinterface UserManager { VrHv)lUr
m}C>ti`VD
public Result listUser(Page page)throws ap.K=-H
rA3$3GLQ-
HibernateException; rV2WnAb[H&
v|gw9
} r A`V}>Xj
CnU*Jb
uW=k K0E
o
m^0}$V
A#K14Ayr
java代码: VQ(j pns5
]_Vx{oT7
hW%TM3l}
/*Created on 2005-7-15*/ t#V!8EpBg
package com.adt.service.impl; (]Z_UTT
0g
+7uGp:
import java.util.List; l}a)ZeR1
Sxnpq Vbk
import net.sf.hibernate.HibernateException; n4s+>|\M
./-5R|fN
import org.flyware.util.page.Page; P9GN}GN%v
import org.flyware.util.page.PageUtil; n D0K).=Q
m!gz3u]rN
import com.adt.bo.Result; ot,jp|N>f~
import com.adt.dao.UserDAO; ?}Z1bH
import com.adt.exception.ObjectNotFoundException; ed]=\Key
import com.adt.service.UserManager; i@C].X
]}Mj)J" m
/** US+Q~GTA
* @author Joa .?D7dyU l1
*/ `n.5f[wC
publicclass UserManagerImpl implements UserManager { %oF}HF.
$I!XSz"/e
private UserDAO userDAO; _ q(ko/T
j:^#rFD4?
/** 9`T)@Uj2n
* @param userDAO The userDAO to set. HD@$t)mn
*/ )YYf1o[+
publicvoid setUserDAO(UserDAO userDAO){ )#EGTRdo
this.userDAO = userDAO; y_'Ub{w
} \<&m&%Zs
h2)yq:87
/* (non-Javadoc) e
h&IPU S
* @see com.adt.service.UserManager#listUser dWM'fg
*!4Z#Y
(org.flyware.util.page.Page) rK@8/?y5
*/ vV'EZ?
public Result listUser(Page page)throws ob+b<HFv
aB*Bz]5;E
HibernateException, ObjectNotFoundException { 5<iV2Hx
int totalRecords = userDAO.getUserCount(); )mI 05
if(totalRecords == 0) }Q)#[#e
throw new ObjectNotFoundException :<ka3<0%
mH54ja2
("userNotExist"); 5 z~1Dw
page = PageUtil.createPage(page, totalRecords); __lM7LFL
List users = userDAO.getUserByPage(page); ,oORW/0iS
returnnew Result(page, users); d)B@x`
} @D)al^]x6
b}OY4~ Y4
} ~9?cn
b
IH;
a:+{f&
_U$<xVnP
efSM`!%j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 NO2XA\
w4_ U0
n3
询,接下来编写UserDAO的代码: [NQOrcAQ
3. UserDAO 和 UserDAOImpl: $[9%QQk5<L
java代码: n+!
AnKq
ZufR{^W
OGBHos
/*Created on 2005-7-15*/ 1 da@3xaF
package com.adt.dao; 3ovWwZ8&
`^91%f
import java.util.List; A]y`7jJ
T\:4qETQF]
import org.flyware.util.page.Page; w _u\p a
rJd,Rdt.
import net.sf.hibernate.HibernateException; [M?}uK ^
zqd@EF6/bz
/** T`/AY?#
* @author Joa sI43@[
*/ OBgkpx*Q
publicinterface UserDAO extends BaseDAO { ,4hJT
he#J|p
publicList getUserByName(String name)throws ImCe K
iy6On,UL
HibernateException; 2^XGGB0
2;xIL]
publicint getUserCount()throws HibernateException; fTzvmC:g7
h,QKd>4:CF
publicList getUserByPage(Page page)throws `{4i)n%e&
.\K_@M
HibernateException; z_g~
^m
L@e'r
} 3sc+3-TF
OL5v).Bb
T}
`x-
y@]_+2Vo
Ulhk$CPA
java代码: }L
&^xe
X#d~zk[r2
\:R%4w#Jv
/*Created on 2005-7-15*/ $v,dz_O*\
package com.adt.dao.impl; ai}mOyJs
8][nmjk0
import java.util.List; X$%'
QU#w%|
import org.flyware.util.page.Page; d^/3('H6
#1J &7F1
import net.sf.hibernate.HibernateException; Yi
.u"sh]
import net.sf.hibernate.Query; TPVVck-T8
BMhy=+\
import com.adt.dao.UserDAO; [vge56h
U
-Y03
/** ,/[6e\0~
* @author Joa rMXN[,|v
*/ 6Vww;1J
public class UserDAOImpl extends BaseDAOHibernateImpl <wZQc
JROM_>mC
implements UserDAO { ?:Mr=]sD
Qg^cf<X{i
/* (non-Javadoc) Kfm5i Q
* @see com.adt.dao.UserDAO#getUserByName F8hw#!Aq
XttqOf
(java.lang.String) KuWWUjCE
*/ 9Kr+\F
publicList getUserByName(String name)throws 'AzDP;6qFI
Y_}mYvJW
HibernateException { uB |Ss
String querySentence = "FROM user in class m_hN*v
Py
$`APHjijN
com.adt.po.User WHERE user.name=:name"; v. %R}Pa
Query query = getSession().createQuery Xf0M:\w=M
jQk*8
(querySentence); pqUCqo!m\
query.setParameter("name", name); `J]fcE%T0R
return query.list(); ttXXy3G#
} 9F6F~::l}
Hip&8NW
/* (non-Javadoc) L93l0eEt
* @see com.adt.dao.UserDAO#getUserCount() BLN^ <X/
*/ Rfn9s(m
publicint getUserCount()throws HibernateException { l6(-I
Tb
int count = 0; h H <J,Wn
String querySentence = "SELECT count(*) FROM O#&c6MDB:
;_8#f%Y#R
user in class com.adt.po.User"; VQY&g;[d
Query query = getSession().createQuery (Lo%9HZ1Mx
b:=TB0Fx?n
(querySentence); 5'0xz.)!
count = ((Integer)query.iterate().next X_qf"|i
g wz7krUTe
()).intValue(); qL5{f(U4<
return count; Jm|+-F@I
} wg ^sGKN
b'P eH\h{
/* (non-Javadoc) =PUt&`1.a
* @see com.adt.dao.UserDAO#getUserByPage jlp:lX
u4m,'XR
(org.flyware.util.page.Page) V I,ACj
*/ }YjX3|8zL=
publicList getUserByPage(Page page)throws >*@y8u*
(* 1v\Q
HibernateException { :*t"8;O[
String querySentence = "FROM user in class =81@o,1w
N+zKr/
com.adt.po.User"; :
m)
Query query = getSession().createQuery Ib|Rf;J~-
CL)lq)1(
(querySentence); >:zK?(qu,N
query.setFirstResult(page.getBeginIndex()) :}r.
.setMaxResults(page.getEveryPage()); uqM yoIc
return query.list(); YWMGB#=
} vgD {qg@
Bt1p'g(V|
} D6CS8
~"
hOFOO_byzO
!E,A7s
KQ`qpX^d
Kk(9O06j
至此,一个完整的分页程序完成。前台的只需要调用 R-NS,i={
Q9Uf.Lh2
userManager.listUser(page)即可得到一个Page对象和结果集对象 /D5`
;=geHiQHA
的综合体,而传入的参数page对象则可以由前台传入,如果用 I+Jm>XN
L,SGT8lL
webwork,甚至可以直接在配置文件中指定。 <cZGxff01
%ThyOl@O
下面给出一个webwork调用示例: fq5_G~c=
java代码: ONx(]
O@MGda9_;
53c 0
E
/*Created on 2005-6-17*/ ?|WoIV.
package com.adt.action.user; !iH-#B-
bKj%s@x
import java.util.List; PlF87j (
8i|w(5m;
import org.apache.commons.logging.Log; LUH"
import org.apache.commons.logging.LogFactory; RG3l.jL
import org.flyware.util.page.Page; 3<k `+,'
u\LiSGePN
import com.adt.bo.Result; .~Fp)O:!
import com.adt.service.UserService; TlI<1/fP}
import com.opensymphony.xwork.Action; fBgEnz/
g8Q5m=O*
/** !Gu%U $d
* @author Joa BYTnrPA&Z;
*/ `(v='$6}
publicclass ListUser implementsAction{ O=v#{ [
-od!J\KCy
privatestaticfinal Log logger = LogFactory.getLog N B\{'
!:|TdYrmj
(ListUser.class); y;t6sM@
E Q4KV
private UserService userService; #O$
6el;Erp
private Page page; [cTe54n
%STliJ
privateList users; %|^OOU}
)x}l3\s
/* *<E]E?
* (non-Javadoc) 'xhcuVl
* /"
${$b{
* @see com.opensymphony.xwork.Action#execute() 'eo
KZX+
*/ i<H wTmm$
publicString execute()throwsException{ B=>RH!&
Result result = userService.listUser(page); Q:|l`*.R
page = result.getPage(); K=C!b?
users = result.getContent(); GwG4LIp
return SUCCESS; '"?C4mbSl
} '"<6.,Ae
=Zu^8 0/
/** V[}4L|ad
* @return Returns the page. >N;F8v
*/ Ypeiy`.
public Page getPage(){ }tH[[4tw,
return page; nSF``pp+
} uch>AuF:
p8kr/uMP ;
/** 7_.11$E=H
* @return Returns the users. V?P,&c?84
*/ ~by]xE1Eg
publicList getUsers(){ a 4=N9X
return users; <+^6}8-
} 1iX)d)(b
Nru7(ag1~
/** G0`h %
* @param page #l4)HV
* The page to set. Kx.X 7R
*/ f'<Q.Vh<
publicvoid setPage(Page page){ Mmo6MZ^
this.page = page; Q\GDrdA
} K,6b3kk
&K43x&mFF
/** uQ=^~K :Z~
* @param users ]c<qM_HWg
* The users to set. ew;ur?
*/ ]J* ,g,
publicvoid setUsers(List users){ \S*$UE]uG
this.users = users; |y h\
} < -uc."6\
'Q
=7/dY3I
/** 2+cNo9f
* @param userService ik"sq}u_]E
* The userService to set. l"q1?kaVg
*/ Tx1vL
publicvoid setUserService(UserService userService){ ?E9D Xg
this.userService = userService; &O)&k
} anj#@U;!
} +vNZW@_$D
!" JfOu
yMZHUd
QDTBWM%
osOVg0Gyj
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, +B'8|5tPX
Z<#hS=eY
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 4<lQwV6=
W(25TbQ
么只需要: 65oWD-
java代码: zOHypazOTq
v}sY|p"
Og2vGzD
<?xml version="1.0"?> p1D[YeF4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K.%U
'`|AI:L
1.0//EN" "http://www.opensymphony.com/xwork/xwork- FVB;\'/
fQ'.8'>T
1.0.dtd"> 0l=+$&D
P_gYz!
<xwork> ?!=iu!J
}C
/]
<package name="user" extends="webwork- :^'O}2NP
4g}FB+[u
interceptors"> ZkP{[^6d\
R*zO
dxY
<!-- The default interceptor stack name !j1[$% =#
>tG+?Y'{
--> 6 CC &Z>
<default-interceptor-ref .6m "'m0;
Uw/l>\
name="myDefaultWebStack"/> vBvNu<v7te
Olfn
<action name="listUser" oyk>vIZ
W%e_~$H0
class="com.adt.action.user.ListUser"> Sf/q2/r?6[
<param x|0:P sE
_TUt9}
name="page.everyPage">10</param> $&Kq*m 0g
<result PF`rWw
{SZ % Xb o
name="success">/user/user_list.jsp</result> <w>/^|]#
</action> ?Pwx~[<1""
D-IR!js ]
</package> ~:lKS;PRuK
o5Y2vmz?9
</xwork> T#!lPH :&h
T;\^#1
C}?0`!Cc%
~AG$5!
pO~c<d}b
.>Z,uT^A
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 r7]"?#
y^Vw`-e
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。 1ndJ+H0H
w%c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 W3&tJ8*3
'PlaM Oy
ciMM^ZRIb
D H^T x
J$9:jE-4
我写的一个用于分页的类,用了泛型了,hoho D);'pKl
m-V02's
java代码: Y&*x4&Lb
G",.,Px
K?u(1
package com.intokr.util; V%CUMH =U
^1jk$$f
import java.util.List; :XV}
c(+d
DlyMJ#a
/** DF1<JdO+
* 用于分页的类<br> LS.r%:$mb
* 可以用于传递查询的结果也可以用于传送查询的参数<br> K(T\9J.
* m@rSz
* @version 0.01 Ep ~wWQh
* @author cheng ~2uh'e3
*/ x.$1<w64t
public class Paginator<E> { Qbeeq6
privateint count = 0; // 总记录数 zz_[S{v!#
privateint p = 1; // 页编号 ?4z8)E9Ju
privateint num = 20; // 每页的记录数 5V-jMB
privateList<E> results = null; // 结果 $R^AEa7
Q;h3v1GC\P
/** o%y;(|4t >
* 结果总数 V+Xl9v4O
*/ I<h=Cj[[
publicint getCount(){ >O]s&34
return count; 8v
yG*UK
} {UH9i'y:t
:DkAQ-<~
publicvoid setCount(int count){ 2L\3S ukj
this.count = count; .tF|YP==
} {<w
+3Va
BH@b1}
/** UP2.]B!d
* 本结果所在的页码,从1开始 (E($3t8
* :WXf.+IA
* @return Returns the pageNo. :#="%
*/ )QY![&k}1z
publicint getP(){ tSv0" L
return p; +=cam/A
} _$/
+D:K
IS]{}Y\3H
/** gbOCR1PBg
* if(p<=0) p=1
L2-^!'
* mog9 jw
* @param p b>cafu
*/ /N^~U&7
publicvoid setP(int p){ \&A+s4c")
if(p <= 0) w@]jpH;WX
p = 1; mVm4fHEYwU
this.p = p; Rt=
X%[YL
} hSqMaX%G
2HOe__Ns
/** M?o{STt
* 每页记录数量 FMu!z
*/ "dN< i
publicint getNum(){ %!.M~5mCd
return num; V 2kWiyN
} ValS8V*N1
g0#q"v55
/** )&Z>@S^
* if(num<1) num=1 K&pM o.
*/ dc^Vc{26Z
publicvoid setNum(int num){ izt^Wi|
if(num < 1) 9NIy#
num = 1; & 5
<**
this.num = num; rFXSO=P?Z
} qw:9zYG}qW
T_L6 t66I
/** !p%@Deu
* 获得总页数 F+j O*F2h
*/ fuSq ={]
publicint getPageNum(){ /GsrGX8
return(count - 1) / num + 1; ;9rTE|n
} lL2-.!]R
l]vohLz
3!
/** fykI,!
* 获得本页的开始编号,为 (p-1)*num+1 tSw>@FM
*/ G.VYp6)5
publicint getStart(){ c2b6B.4
return(p - 1) * num + 1; _:,.yRez
} w yD%x(
I#l;~a<9z
/** >_#)3K1y8
* @return Returns the results. g.*&BXZi
*/ {a4xF2
publicList<E> getResults(){ Pe,;MP\2
return results; #1l7FT?q
} 5 LMj!)3
!V(`ZH
public void setResults(List<E> results){ oYq,u@oM
this.results = results; sQ(1/"gb
} lS{4dvr?w
lV7IHX1P
public String toString(){ 4 ?2g&B\
StringBuilder buff = new StringBuilder n2na9dX)w
[a D:A
(); xT+
;w[s
buff.append("{"); Z}f^qc+
buff.append("count:").append(count); XIN5a~[z*
buff.append(",p:").append(p); LD@7(?mlU
buff.append(",nump:").append(num); ^?Vq L\V5
buff.append(",results:").append DB Xm
M7U:g}
(results); 1E^{B8cm
buff.append("}"); m3%ef
return buff.toString(); LY1KQu Y
} ftW{C1,U7
+G\0L_B
} O2@"
w23
Q2R-z^pd
H:E5xz3VQ