Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 E>I\m!ue
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0Fc^c[
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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 >K;DBy*
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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 o|G[/o2
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分页支持类: l' mdj!{&
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java代码: +S6(Fvp
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package com.javaeye.common.util; X 7R&>Pf
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import java.util.List; DmtCEKa
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publicclass PaginationSupport { wG@f~$
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publicfinalstaticint PAGESIZE = 30; 67b
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privateint pageSize = PAGESIZE; Ek6z[G`
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privateList items; 9y+0Zj+.
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privateint totalCount; ;_p$5GVR|
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privateint[] indexes = newint[0]; ISHzlEY
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privateint startIndex = 0; K
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public PaginationSupport(List items, int urhOvC$a
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totalCount){ 8}K^o>J&K
setPageSize(PAGESIZE); CuT50N;tk
setTotalCount(totalCount); 38#Zlcf
setItems(items); 8_Nyy/K#F
setStartIndex(0); of=N+
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} Mj6
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public PaginationSupport(List items, int lc[)O3,,B
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totalCount, int startIndex){ G
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setPageSize(PAGESIZE); /*2)|2w
setTotalCount(totalCount); IqAML|C
setItems(items); [9^lAhX
setStartIndex(startIndex); ("KtJ
} lG5KZ[/Or
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public PaginationSupport(List items, int 5=_bK^Am
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totalCount, int pageSize, int startIndex){ fSF_O}kLp
setPageSize(pageSize); gY&WH9sp?9
setTotalCount(totalCount); s[bQO1g;*
setItems(items); \IaUsx"#o{
setStartIndex(startIndex); ZM16 ~k
} U#Wg"W{
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publicList getItems(){ UR~ s\m
return items; FBxg^g%PB@
} \q@Co42n\
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publicvoid setItems(List items){ zfw=U
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this.items = items; qV0GpVJZU?
} wxo*\WLe
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publicint getPageSize(){ #y-R*4G
return pageSize; Du #>y!
} Cto>~pV
c] -
publicvoid setPageSize(int pageSize){ 7M)<Sv
this.pageSize = pageSize; E#R1
} hg2Ywzfm-
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publicint getTotalCount(){ ik#ti=.
return totalCount; H'+3<t>
} !dq$qUl/
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publicvoid setTotalCount(int totalCount){ #mYe@[p@
if(totalCount > 0){ UD=[::##
this.totalCount = totalCount; q P0UcG
int count = totalCount / 22'Ra[
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pageSize; xXlx}C
if(totalCount % pageSize > 0) `S+n,,l
count++; iJH?Z,Tjf
indexes = newint[count]; g/frg(KF
for(int i = 0; i < count; i++){ ;nrkC\SYh:
indexes = pageSize * t$
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} 6l:uQz9
}else{ Dn)B19b
this.totalCount = 0; B@v
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} #jJ0Mxg
} ZUD{V
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publicint[] getIndexes(){ *j(UAVp
return indexes; $_3)m
} 6"?#E[ #[
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publicvoid setIndexes(int[] indexes){ ep4?;Qmho
this.indexes = indexes; W[R`],x`
} V qcw2
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publicint getStartIndex(){ ,Wtgj=1!.
return startIndex; &@FufpPw/
} lL'Bop@
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publicvoid setStartIndex(int startIndex){ yuC|_nL
if(totalCount <= 0) &dPUd~&EL
this.startIndex = 0; Yxy!&hPLv:
elseif(startIndex >= totalCount) 9oIfSr,y
this.startIndex = indexes Sk:x.oOZ
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[indexes.length - 1]; -Kw7!
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elseif(startIndex < 0) Kn1T2WSAg
this.startIndex = 0; `6RccEm
else{ \r9E6LLX'
this.startIndex = indexes #l h'
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[startIndex / pageSize]; V CVKh
} LcT;7yv
} F|cli
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publicint getNextIndex(){ L)8%*X
int nextIndex = getStartIndex() + U_hzSf
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pageSize; nBLb1T
if(nextIndex >= totalCount) Q~/=p>=uu
return getStartIndex(); =J"c'Z>.
else aK_k'4YTm
return nextIndex; }u1h6rd `
} 'Fc$?$c\
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publicint getPreviousIndex(){ gLY15v4?
int previousIndex = getStartIndex() - @=%g{
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pageSize; >3*a&_cI=k
if(previousIndex < 0) =f23lA
return0; JNT|h zV
else F@HJ3O9
return previousIndex; A2p% Y},
} C9_[ke[1D
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} 6oFA=CjU{
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抽象业务类 I-=Ieq"R9
java代码: _k;HhLj`
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/** t BG
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* Created on 2005-7-12 ;JMmr-@
*/ cnRgzj<ek
package com.javaeye.common.business; bvHQ #:}H
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import java.io.Serializable; 7F_N{avr
import java.util.List; kZ]pV=\Y*
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import org.hibernate.Criteria; (Q&O'ng1
import org.hibernate.HibernateException; @6%7X7m
import org.hibernate.Session; }$sTnea
import org.hibernate.criterion.DetachedCriteria; Ck>]+rl
import org.hibernate.criterion.Projections; #3{{[i(;i
import 4#.Q|vyl]"
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org.springframework.orm.hibernate3.HibernateCallback; :."6 g)T
import I[?bM-
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org.springframework.orm.hibernate3.support.HibernateDaoS yhI;FNSf
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upport; lgD%
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends Oqt{ uTI~
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HibernateDaoSupport { +JM@ kdE5b
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privateboolean cacheQueries = false; Ed{sC[j=
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privateString queryCacheRegion; `Q/\w1-Q
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publicvoid setCacheQueries(boolean 6#.9T;&
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cacheQueries){ cct/mX2&~
this.cacheQueries = cacheQueries; .6I'V3:Kg
} :h/v"2uDN
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publicvoid setQueryCacheRegion(String ITEf Q@#jU
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queryCacheRegion){ ?GtI.flV
this.queryCacheRegion = NB86+2stu
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queryCacheRegion; :Bu)cy#/[
} _meW9)B
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publicvoid save(finalObject entity){ Z c#Jb
getHibernateTemplate().save(entity); !,rF(pz
} D~|q^Ms,%
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publicvoid persist(finalObject entity){ Y7 K2@257
getHibernateTemplate().save(entity); E1`_[=8a9
} R~|(]#com
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publicvoid update(finalObject entity){ 2- (}=N
getHibernateTemplate().update(entity); B@*!>R
} -v|lM8
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publicvoid delete(finalObject entity){ *J
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getHibernateTemplate().delete(entity); yF_/.m I
} _34%St!lg
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publicObject load(finalClass entity, <^'IC9D]
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finalSerializable id){ o>T+fBHE
return getHibernateTemplate().load y\[* mgl:
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(entity, id); Tj\hAcD
} ?YDMl
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publicObject get(finalClass entity, O*x~a;?G
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finalSerializable id){ #`l&HV
return getHibernateTemplate().get I3i zLi
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(entity, id); 4d}n0b\d
} '<*%<J{(
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publicList findAll(finalClass entity){ ~"4Cz27
return getHibernateTemplate().find("from %M`zkA2]J
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" + entity.getName()); B(6*U~Kn%
} .|TF /b]
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publicList findByNamedQuery(finalString =NnG[#n%
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namedQuery){ $
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return getHibernateTemplate 5Z"N2D)."
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().findByNamedQuery(namedQuery); =4U$9jo!;
} ,JTyOBB<I
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publicList findByNamedQuery(finalString query, L'"c;FF02i
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finalObject parameter){ #e[r0f?U
return getHibernateTemplate i }Zz[b
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().findByNamedQuery(query, parameter); x") Bmw$
} : t75iB=
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publicList findByNamedQuery(finalString query, 7 n^1H[q
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finalObject[] parameters){ 8493O x4 O
return getHibernateTemplate i=pfjC
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().findByNamedQuery(query, parameters); JS<w43/j
} Ad>@8^
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publicList find(finalString query){ xgM\6e
return getHibernateTemplate().find g2 mq?q(g
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(query); ]gF=I5jn]
} w
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publicList find(finalString query, finalObject Mii&doU
9y} J|z
parameter){ NqFfz9G)
return getHibernateTemplate().find v:>sS_^
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(query, parameter); +bb-uoZf
} wqap~X
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public PaginationSupport findPageByCriteria Mpk7$=hjc
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(final DetachedCriteria detachedCriteria){ O0bOv S
return findPageByCriteria ra_TN;(
=KD[#au6a
(detachedCriteria, PaginationSupport.PAGESIZE, 0); t#-4edB,
} +Q[SddI
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public PaginationSupport findPageByCriteria KF!d?
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(final DetachedCriteria detachedCriteria, finalint 300[2}Y]
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startIndex){ /c4$m3?]
return findPageByCriteria p!<PRms@
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(detachedCriteria, PaginationSupport.PAGESIZE, uaCI2I
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startIndex); :3J`+V}9;
} ]XL=S|tIq
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public PaginationSupport findPageByCriteria yLl:G;
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(final DetachedCriteria detachedCriteria, finalint tn(6T^u
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pageSize, 9'|_1Q.b^
finalint startIndex){ J%!vhQ
return(PaginationSupport) 9J<vkxG9`
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getHibernateTemplate().execute(new HibernateCallback(){ 1,we:rwX
publicObject doInHibernate 1$:O9{F
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(Session session)throws HibernateException { i~5'bSqc
Criteria criteria = =Pp-9<&S
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detachedCriteria.getExecutableCriteria(session); &b-&0rTqz
int totalCount = !2/o]_K@+
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((Integer) criteria.setProjection(Projections.rowCount ,XN4Iy#BZl
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()).uniqueResult()).intValue(); w7\
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criteria.setProjection N%=,S?b
>{Xyl):
(null); d*@K5?O.
List items = F+W{R+6
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criteria.setFirstResult(startIndex).setMaxResults O>"
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(pageSize).list(); 7x*C`
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PaginationSupport ps = ws
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z$(`{
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new PaginationSupport(items, totalCount, pageSize, J$`5KbT3
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startIndex); 5F]2.<i
return ps; _b *gg
} R(f%*S4
}, true); ndk~(ex|j
} wawJZ+V
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public List findAllByCriteria(final &F'n
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DetachedCriteria detachedCriteria){ EQ"+G[j~x
return(List) getHibernateTemplate Z8f?uF
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().execute(new HibernateCallback(){ <" 0b8 Z
publicObject doInHibernate P#rS.CIh
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(Session session)throws HibernateException { Q Vl"l'e8
Criteria criteria = _! ?a9
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detachedCriteria.getExecutableCriteria(session); N7)K\)DS!z
return criteria.list(); 1DH P5q
} o}52Qio
}, true); c68,,rJO]i
} {qs>yQ6a:-
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public int getCountByCriteria(final L;6{0b58$
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DetachedCriteria detachedCriteria){ f'Oj01[
Integer count = (Integer) 9j0o)]
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getHibernateTemplate().execute(new HibernateCallback(){ /8 "rCh|m-
publicObject doInHibernate }z2[w@M
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(Session session)throws HibernateException { o Z%oP V:
Criteria criteria = Pa?C-Xn^
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detachedCriteria.getExecutableCriteria(session); E0u&hBd3_
return c&PaJm
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criteria.setProjection(Projections.rowCount QM7BFS;
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()).uniqueResult(); xgvwH?<
} B!4~A{
}, true); L} K8cB
return count.intValue(); sdN1BV2
} AH:0h X6+
} x((Rm_'
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用户在web层构造查询条件detachedCriteria,和可选的 nUCOHVI7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9vCCE[9
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PaginationSupport的实例ps。 1=PTiDMJ<*
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ps.getItems()得到已分页好的结果集 !bCaDTz
ps.getIndexes()得到分页索引的数组 h&rZR`g
ps.getTotalCount()得到总结果数 Q9&H/]"v
ps.getStartIndex()当前分页索引 z00,Vr^m
ps.getNextIndex()下一页索引 {=;<1PykLb
ps.getPreviousIndex()上一页索引 _
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 1-|aeJ
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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 Mt@Ma ]!
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一下代码重构了。 |<MSV KW
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我把原本我的做法也提供出来供大家讨论吧: Q07&7SH_
FB
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首先,为了实现分页查询,我封装了一个Page类: FbXur- et^
java代码: %8xK BL]J
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/*Created on 2005-4-14*/ BKYyc6iE
package org.flyware.util.page; fm!\**Q1
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/** _ER. AKY
* @author Joa `A-
* vhDtjf/*
*/ M(n@ytz
publicclass Page { sD|}?7
rE0%R+4?
/** imply if the page has previous page */ 5kojh _\
privateboolean hasPrePage; wVX2.D'n<
*U`R<mV\
/** imply if the page has next page */ e\!Aoky
privateboolean hasNextPage; :#D~j]pP
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/** the number of every page */ g8@F/$HY
privateint everyPage; \9`.jB~<
*Rxn3tR7
/** the total page number */ Rr}m(e=
privateint totalPage; $#(j2sL1
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Tao
/** the number of current page */ .hnq>R\
privateint currentPage; p6ryUJc6
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/** the begin index of the records by the current nYe:$t3F=
9Q'[>P=1
query */ p1W6 s0L
privateint beginIndex; M`E}1WNQ?]
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/** The default constructor */ wJ"]H!r0
public Page(){ 4um^7Ns)7
0%)T]SDS
} k=&n>P
}7_$[r'_oI
/** construct the page by everyPage E()%IC/R
* @param everyPage Ys|SacWC
* */ ?Cx=!k.
public Page(int everyPage){ &(e5*Q
this.everyPage = everyPage; cwzgIm+
} C>SOd]
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/** The whole constructor */ A6 `a
public Page(boolean hasPrePage, boolean hasNextPage, cIcu=U
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int everyPage, int totalPage, f.$*9Fkw
int currentPage, int beginIndex){ ZB}A^X
this.hasPrePage = hasPrePage; %jHe_8=o
this.hasNextPage = hasNextPage; 1U?5/Ja
this.everyPage = everyPage; H!>>|6OPF
this.totalPage = totalPage; v["_t/_
this.currentPage = currentPage; !~V^GlY
this.beginIndex = beginIndex; 5"X@<;H%
} %0Qq~J@Lu
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/** %?Q&a ]
* @return 9ExI,
* Returns the beginIndex. \L`x![$~q
*/ $\|Q+ 7lQ
publicint getBeginIndex(){ p}5413z5Z=
return beginIndex; SpYmgL?wJ
} FZIC|uz
N;k )>
/** <lLJf8OK
* @param beginIndex M?GkHJ %!
* The beginIndex to set. ia3!&rZ
*/ rm-;Z<
publicvoid setBeginIndex(int beginIndex){ PB!XApTb
this.beginIndex = beginIndex; y,bDi9*|
} vVrM[0*c
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/** v`]y:Ku|wR
* @return >Bu9 D
* Returns the currentPage. U<E]c 4*
*/ d={o|Mf
publicint getCurrentPage(){ YBR)S_C$_
return currentPage; Z`U+a
} Tu5p`p3-j
ael] {'h]
/** ZKq#PB/.
* @param currentPage UEhFId
* The currentPage to set. M{)&SNI*C
*/ j%Xa8$
publicvoid setCurrentPage(int currentPage){ "a3?m)
this.currentPage = currentPage; H8=:LF
} !l Egta[Ql
F^aD#
/** Tku6X/LF
* @return g"(@+\XZH"
* Returns the everyPage. u[oV
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*/ T7Y}v,+-
publicint getEveryPage(){ ]>Gi_20*.
return everyPage;
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} &fl RrJ
EU04U
/** #TC}paIpj
* @param everyPage y)a)VvU":
* The everyPage to set. &U7h9o H
*/ MvnQUZ
publicvoid setEveryPage(int everyPage){ ^!0z+M:>^
this.everyPage = everyPage; M ?AX:0
} 8FZC0j.^DH
s@{~8cHgU
/** ^E:-Uy
* @return ByO?qft>u
* Returns the hasNextPage. /y6f~F
*/ cza_LO(
publicboolean getHasNextPage(){ 2eA.04F
return hasNextPage; 3D1y^I
} ts}OE
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/** Yyr9Kj:
* @param hasNextPage -A=3W3:C
* The hasNextPage to set. "v(pluN|
*/ VaGQre
publicvoid setHasNextPage(boolean hasNextPage){ ICr.Gwe3_
this.hasNextPage = hasNextPage; 6}!1a?X
} zSU,le
oif|X7H;
/** 4*Gv0#dga
* @return I%GQ3D"=
* Returns the hasPrePage. v Y0ESc{
*/ 8DY:a['-d
publicboolean getHasPrePage(){ C/#pK2xY
return hasPrePage; 'Cz*p,
} \7>*ULP
S' kgpF"bm
/** O`"~AY&
* @param hasPrePage +!E9$U>6%
* The hasPrePage to set. Zq<j}vVJ
*/ 0a^bAEP
publicvoid setHasPrePage(boolean hasPrePage){ |WEl5 bNc3
this.hasPrePage = hasPrePage; X!mJUDzh]
} u[Si=)`VPk
`JpFqZ'58
/** 6vR6=@(`>
* @return Returns the totalPage. }qhYHC
* }!R*Q`m
*/ -2 >s#/%
publicint getTotalPage(){ o 9/,@Ri\5
return totalPage; c5b}q@nH
} v9Sk\9}S
32?'jRN(ue
/** 1X5Yp |Ho
* @param totalPage NsSZ?ky
* The totalPage to set. l|E4 7@#
*/ >]ZE<.
publicvoid setTotalPage(int totalPage){ P}UxA!
this.totalPage = totalPage; @ =~k[o
} .`5|NUhN
|+::sL\r
} qNP)oU92
N6\rjYx+7
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i*m;kWu,
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 |iX>hJSl
0B!(i.w
个PageUtil,负责对Page对象进行构造: D}lqd Ja
java代码: dE_"|,:
)h&@}#A09
(dD7"zQ
/*Created on 2005-4-14*/ 4%w<Ekd
package org.flyware.util.page; bv'>4a
la w$LL
import org.apache.commons.logging.Log; kp* !
import org.apache.commons.logging.LogFactory; JGTsVa2
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/** naH(lz|v
* @author Joa %.r\P@7/Q
* p9u*l
*/ A%HIfSzQBS
publicclass PageUtil { $p4e8j[EJ
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privatestaticfinal Log logger = LogFactory.getLog Sw,*#98
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(PageUtil.class); 6Aq]I$
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/** v
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* Use the origin page to create a new page gh\u@#$8
* @param page ,=4,eCS
* @param totalRecords Z|Rc54Ct
* @return @KU;'th
*/ 1zH?.-
publicstatic Page createPage(Page page, int 'N+;{8C-{
:q*w_*w
totalRecords){ rTR"\u7&H
return createPage(page.getEveryPage(), K Cw
jX8)Ov5Mv
page.getCurrentPage(), totalRecords); 0m4M@94
} OG?7(
UJ
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/** tP*Kt'4W
* the basic page utils not including exception 8>#ZU]cG
GdNhEv
handler OUF%DMl4
* @param everyPage gj
@9(dk%
* @param currentPage cnQ2/ZZp~
* @param totalRecords 3~Fag1Hp
* @return page .Y]0gi8z
*/ P-gj SE|yh
publicstatic Page createPage(int everyPage, int .BBJhXtrdu
qve'Gm)
currentPage, int totalRecords){ La9}JvQoX
everyPage = getEveryPage(everyPage); K-#d1+P+
currentPage = getCurrentPage(currentPage); /KF@Un_Ow
int beginIndex = getBeginIndex(everyPage, BlU&=;#r5>
e1h7~ j
currentPage); DC*MB:c#U
int totalPage = getTotalPage(everyPage, BA1uo0S `S
}*QK;#NEc
totalRecords); EYj~Xj8_
boolean hasNextPage = hasNextPage(currentPage, jQ3dLctn
G"J
nQ
totalPage); iJ^}{-
boolean hasPrePage = hasPrePage(currentPage); rZ3ji(4HS
ou~$XZ7oi
returnnew Page(hasPrePage, hasNextPage, >4Tk#+%Jj
everyPage, totalPage, S sW<,T
currentPage, .x,y[/[[)
OzrIiahz/
beginIndex); u%z'.#r; a
} (XmmbAbVom
b/
\EN)
privatestaticint getEveryPage(int everyPage){ ;#9?3Os
return everyPage == 0 ? 10 : everyPage; QJ(%rvn3
} =LV-n
U!r8}@
privatestaticint getCurrentPage(int currentPage){ XK3O,XM
return currentPage == 0 ? 1 : currentPage; ^O@eyP
} K'J_AMBL
I@6+AU~,6
privatestaticint getBeginIndex(int everyPage, int ZwLr>?0$
p
pMHl<HH
currentPage){ \zg R]|
return(currentPage - 1) * everyPage; eg}g}a
} 6_QAE6A
~&T U
privatestaticint getTotalPage(int everyPage, int iD|~$<9o
JFX}))7
totalRecords){ ~^a>C
int totalPage = 0; T[1iZ
(:OMt2{r
if(totalRecords % everyPage == 0) *1kFy_Gx
totalPage = totalRecords / everyPage; aH uMm&
else qKd ="PR}
totalPage = totalRecords / everyPage + 1 ; l9Ol|Cb&
n8; p]{
return totalPage; EG`AkWy
} cb]X27uww
q#mL-3OQ
privatestaticboolean hasPrePage(int currentPage){ bH/4f93Nb
return currentPage == 1 ? false : true; 77[TqRLf
} ;k `51=Wi
!;*flr`/
privatestaticboolean hasNextPage(int currentPage, b_F1?:#
)2Sh oFF
int totalPage){ PaQ lQ#
return currentPage == totalPage || totalPage == grgs r_)[
_d3Z~cH
0 ? false : true; 6}N`YOJ.
} L5`k3ap|
6#*_d,xQT
Mi|13[p{
} dL%*;
Fy<:iv0>t
8\P,2RSnt
WJONk_WAc
Bh=t%#y|`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 [HWVS
qsoq1u,?
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \ . #Y
&}e>JgBe0
做法如下: 'a+^= c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {Dl@/fz
z;oia!9z
的信息,和一个结果集List: TIiYic!_~
java代码: \MRd4vufv
ed',\+.uB
ZYWGP:Y
/*Created on 2005-6-13*/ &v((tZ
package com.adt.bo; i*:QbMb
JRz)A4P
import java.util.List; N9G xJ6
.lb]Xa*n
import org.flyware.util.page.Page; K2x2Y=
`B3-#!2X
/** Izu____
* @author Joa 4w ,L
*/ w%qnH e9
publicclass Result { X:Wd%CHP
Yh1nXkA!V
private Page page; Q<AOc\oO
~HGSA(
private List content; SF;\*]["f
l VD{Y`)
/** P-2DBNB7
* The default constructor EoPvF`T
*/ ^$'z#ZN1
public Result(){ AA^K/y
super(); 9;6)b0=$
} 0M;El2
P$
QnS^ G{
/** ._tEDY/1m
* The constructor using fields 5`fUR/|[
*
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* @param page vv,<#4d
* @param content QAxy?m,'
*/ PZ6R+n8
public Result(Page page, List content){ Q`8-|(ngw
this.page = page; $Xt""mlQ
this.content = content; ^"|q~2
} Ey:?!
"Y:>^F;
/** &Wa3/mWK
* @return Returns the content. azIhp{rHw
*/ i@rUZYF
publicList getContent(){ l#v52
return content; z{ eZsh
b
} D>{`I'
J#Y0R"fo
/** $*X?]?
* @return Returns the page. J1O1! .
*/ ($<&H>j0
public Page getPage(){ &1T)'Bn
return page; 3xz~##
} ?Ybq]J\q
RYvcuA)
/** %,vq@..^
* @param content
YC6guy>
* The content to set. T;B FO5G@
*/ L bJf5xdi
public void setContent(List content){ 6c^?DLy9B
this.content = content; e)?}2
} +$L}B-F
$t& o(]m
/** ]'%
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* @param page ;Ngk"5
* The page to set. OHAU@*[lM
*/ S+.>{0!S"
publicvoid setPage(Page page){ iNkN'("
this.page = page; ~
e?af
} *FEJ5x
} FXT^r3
+p>h` fc
q)?!]|pZ
~:{ mKc
vde!k_,wZ
2. 编写业务逻辑接口,并实现它(UserManager, ^"I@ 8 k
Z}0{FwW"4
UserManagerImpl) M .6BFC
java代码: qZ>_{b0f
2>X yrG
mgH~GKf^
/*Created on 2005-7-15*/ T$0)un
package com.adt.service; A405igF
aTm R~k
import net.sf.hibernate.HibernateException; ML|?H1m>
9C?SEbC
import org.flyware.util.page.Page; b4^O=
aKW-(5<JW
import com.adt.bo.Result; :D3:`P>,c
1hi
/** 93.\.&L\
* @author Joa ]pB5cq7o
*/ q,7W,<-
publicinterface UserManager { `'iO+/;GY
;lE=7[UJ3X
public Result listUser(Page page)throws #E
Bdg
Jjj;v2uSK
HibernateException; Ppl :_Of
j|[$P4w}U
} 3r[F1z2B
V[%IU'{:
-a|b.p
ua=7YG
V!. Y M)B
java代码: onmkg}&_
#'f5owk>,
ddl]!
^IK
/*Created on 2005-7-15*/ CIo`;jt K
package com.adt.service.impl; $ Lfbt=f
=pmG.>Si
import java.util.List; 4s%zvRu
vCt][WX(
import net.sf.hibernate.HibernateException; 7]?y
_%kT
C[Q4OAFG
import org.flyware.util.page.Page; U:7w8$_
import org.flyware.util.page.PageUtil; /YPG_,lRA
D0bpD
import com.adt.bo.Result; ]Q.S Is
import com.adt.dao.UserDAO; Sru0j/|H\
import com.adt.exception.ObjectNotFoundException; *^{j!U37s
import com.adt.service.UserManager; /oEDA^qx
n4{?Odrf
/** 4IOqSB|
* @author Joa &x*l{s[
*/ 5G'2 Wby'#
publicclass UserManagerImpl implements UserManager { a(fiW%eFb
Vr&
GsT
private UserDAO userDAO; WRbdv{1E
p"6[ S
/** lBG=jOS
* @param userDAO The userDAO to set. xa_ IdkV
*/ wO!>kc<
publicvoid setUserDAO(UserDAO userDAO){ hEo$Jz`
this.userDAO = userDAO; ]==7P;_-
} K~-V([tWg
2 7dS.6
/* (non-Javadoc) $SA
@ "
* @see com.adt.service.UserManager#listUser f$}g'r zl
KMfIp:~
(org.flyware.util.page.Page) 4Hyp]07
*/ p;o "i_!
public Result listUser(Page page)throws &'PLOyWw
L?a4>uVY
HibernateException, ObjectNotFoundException { 2\64~a^
int totalRecords = userDAO.getUserCount(); Hxac#(,7
if(totalRecords == 0) sng6U;Z
throw new ObjectNotFoundException Zd-QZ<c";t
3zfiegY@wm
("userNotExist"); ~3Qa-s;g
page = PageUtil.createPage(page, totalRecords); $u,A/7\s
List users = userDAO.getUserByPage(page); B&KIM{j\
returnnew Result(page, users); BUi,+NdIk
} Cv>~%<
]3]B$
} .8'uIA{_2
32j#kJ W
9ec#'i=
Ai 8+U)
_a$5"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 pox;NdX7
Wo9=cYC)
询,接下来编写UserDAO的代码: c?c"|.-<p
3. UserDAO 和 UserDAOImpl: x) %"i)
java代码: *<{hLf
"tmu23xQ
0#8lg@e8
/*Created on 2005-7-15*/ b/T k$&
package com.adt.dao; pXQ$n:e
8&+u+@H
import java.util.List; :*l\j"fX5
N7 _rVcDe
import org.flyware.util.page.Page; &C9)%5O)
*fy aAv
import net.sf.hibernate.HibernateException; P?8$VAkj
n
sN n>{
/** BdvpG
* @author Joa y{P~!Yn|
*/ 8<6@O
publicinterface UserDAO extends BaseDAO { d[;&2Jz*
%[L/JJbP&Z
publicList getUserByName(String name)throws &R<K>i
HDE5Mg "
HibernateException; ]d|M@v~c4
R5},E
publicint getUserCount()throws HibernateException; O#8lJ%?
X,8Zn06M
publicList getUserByPage(Page page)throws _-v$fDrz
SBi4i;qD
HibernateException; :<
]sJfN
u1z!OofN>
} i3(5
'
Z]Z&PbP
\`/ P*
G%jV}7h
X2np.9hie
java代码: /bC@^Y&}
ja{x}n*5
}Vm'0
/*Created on 2005-7-15*/ g+&wgyq5
package com.adt.dao.impl; "KC3+:tm
jW| ,5,43
import java.util.List; ?^8.Sa{
0+_;6
import org.flyware.util.page.Page; {FC<vx{42
_39VL
import net.sf.hibernate.HibernateException; F
Zt;D
import net.sf.hibernate.Query; 7=wQ#bq"1P
#aP;a-Q|k
import com.adt.dao.UserDAO; #7J3,EV
0o.h{BN
/** xTZJ5iZ17
* @author Joa i MS4<`
*/ 7{rRQ~s&g9
public class UserDAOImpl extends BaseDAOHibernateImpl PIsXX#`7;
Y\(?&7Aax
implements UserDAO { puF*WxU)
#Oa`P
/* (non-Javadoc) h9. Yux
* @see com.adt.dao.UserDAO#getUserByName Sn;q:e3i{A
nu16L$]
(java.lang.String) P^BSl7cT
*/ pqbKPpG
publicList getUserByName(String name)throws D/2;b;-
u<+RA
HibernateException { OtT*)8*c
String querySentence = "FROM user in class aMgg[g9>t
EY :EpVin
com.adt.po.User WHERE user.name=:name"; M?ElD1#Z
Query query = getSession().createQuery Qeq=4Nq
RHt~:D3*
(querySentence); BJZGQrsz
query.setParameter("name", name); eTtiAF=bW
return query.list(); [s-!tE3-
} {]y!2r
#vcQ =%;O
/* (non-Javadoc) SR/
"{\C
* @see com.adt.dao.UserDAO#getUserCount() 8vvNn>Q
*/ DeN$YE#*
publicint getUserCount()throws HibernateException { -K5u5l}
int count = 0; m?1AgsBR
String querySentence = "SELECT count(*) FROM uKT\\1Jrq
{~=gKZ:-@
user in class com.adt.po.User"; D rouEm
Query query = getSession().createQuery yyjgPbLN=
61z^(F$@
(querySentence); z8PV&o
count = ((Integer)query.iterate().next **n109R
Q>/[*(.Wd
()).intValue(); %BkPkQA
return count; C9`x"$
} s:sk`~2<gd
).r04)/
/* (non-Javadoc) g$Nsu:L
* @see com.adt.dao.UserDAO#getUserByPage ;q2e[ y
n{%[G2.A
(org.flyware.util.page.Page) d]l(B+\vf
*/ !R$t>X
publicList getUserByPage(Page page)throws 3.04Toq!
%e=UYBj"
HibernateException { (ZK(ODn)i
String querySentence = "FROM user in class ur/:aI
@IBU{{
com.adt.po.User"; 1,sD'iNb
Query query = getSession().createQuery g6q67m<h
] 2lhJ
(querySentence); 7t/C:2^&
query.setFirstResult(page.getBeginIndex()) onUF@3V
.setMaxResults(page.getEveryPage()); ZOHGGO]1M
return query.list(); }?%5Ae7l,
} r1xhplHH@
-;[,`g(f
} -<n]Sv;V
h&t9CpTfeJ
+dK;\wT
VQ`a-DL
nnnq6Z}
至此,一个完整的分页程序完成。前台的只需要调用 3C;nC?]K
JwmH_nJ(
userManager.listUser(page)即可得到一个Page对象和结果集对象 4kf8Am(
\&X*-T[]j
的综合体,而传入的参数page对象则可以由前台传入,如果用 E#+|.0*!s
+C9l7 q
webwork,甚至可以直接在配置文件中指定。 G(7WUMjl
9GVv[/NAb
下面给出一个webwork调用示例: C%kIxa)
java代码: @EB2I+[
Z;GZ?NOlY
F%q}N,W
/*Created on 2005-6-17*/ *Q2}Qbu
package com.adt.action.user; Ceak8#|4
|jyoT%SQ
import java.util.List; =(>pv,
p3{ 3[fDx
import org.apache.commons.logging.Log; Q.L.B7'e7
import org.apache.commons.logging.LogFactory; z]
teQaUZ
import org.flyware.util.page.Page; R9lb<`
Z\*jt B:
import com.adt.bo.Result; co%-d
import com.adt.service.UserService; 6"Rw&3D?
import com.opensymphony.xwork.Action; +d,Z_ 6F
0N>R!
/** l)(
3]
* @author Joa A<s9c=d6
*/ qCgoB 0
publicclass ListUser implementsAction{ SpX6PwM
'#@tovr
privatestaticfinal Log logger = LogFactory.getLog qFYM2
ju?D=n@i
(ListUser.class); G^/8lIj
rnTjw
"%
private UserService userService; $y+Bril5W
o@tc
private Page page; <;nhb
[&a=vE
privateList users; YhNO{4D
/%w3(e
/* GbN|!,X1m
* (non-Javadoc) *k
^?L
* :f5"w+
* @see com.opensymphony.xwork.Action#execute() [}t^+^/
*/ !qF t:{-h
publicString execute()throwsException{ ?_bzg'
Result result = userService.listUser(page); V`XtGTx
page = result.getPage(); P+t`Rw
users = result.getContent(); Ov PTgiI!N
return SUCCESS; "s5[w+,R
} zsuXN *
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/** 'PVxc%[
* @return Returns the page. R k@xv;t;
*/ 2 VyJ
public Page getPage(){ R\d)kcy4
return page; sW]fPa(cn,
} I&G"{Dl94
?."YP[;
/** 2Bg0
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* @return Returns the users. bL]NSD
*/ |Y&&g=7
publicList getUsers(){
c
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return users; 6@;
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} #:LI,t
| )M>;q
/** o6T'U#7P
* @param page @J UCXm
* The page to set. #cy;((z uB
*/ U/l3C(bc!
publicvoid setPage(Page page){ wY6m^g$h3
this.page = page; >s|zrS)
} pDV8B/{
A{Dy3tm=
/** bx8;`QMX
* @param users {YigB
* The users to set. K@>($BX]
*/ hX9vtV5L
publicvoid setUsers(List users){ H^r;,Q$9
this.users = users; JOFQyhY0>m
} ^ ^T e
"9bd;Tt:
/** vkE a[7
* @param userService ]<Kkq!
* The userService to set. "';K$&,[
*/ C
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publicvoid setUserService(UserService userService){ d !=AS
this.userService = userService; ?3=y]Vb+
} tqXr6+!Q
} ,A9_xdv5
'
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x,: DL)$1
5~GH*!h%;
,zVS}!jRhy
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ]m<z
>&%#`PKT
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 !THa?U;
c%@<
h6
么只需要: Ssg1p#0J
java代码: bAS/cuZs
Jy?; <
g?E8zf `
<?xml version="1.0"?> F0x'^Z}Q;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7*\CfqrU
n5>OZ3 E@
1.0//EN" "http://www.opensymphony.com/xwork/xwork- d`9ofw~3=
z,xGjSP
1.0.dtd"> :Fh#"<A&&
Fv$oXg/
<xwork> :e rfs}I
V
0z`p"
<package name="user" extends="webwork- r@u8QhD
i#bcjH
interceptors"> 9zE/SDu7\
%i5tf;x6i
<!-- The default interceptor stack name '@dk3:3t
>yf}9Zs
--> ~`X$bF
<default-interceptor-ref g$h`.Fk,
N.UeuLz
name="myDefaultWebStack"/> ,xI
FF-[0
&t:~e" 5<
<action name="listUser" g1v=a
$|m'~AmI
class="com.adt.action.user.ListUser"> u5N&W n{
<param lsA?|4`mn
%sCG}?
y
name="page.everyPage">10</param> sWv!ig_
<result l/-qVAd!q
wQX18aF/#d
name="success">/user/user_list.jsp</result> ~CuJ$(9Y
</action> R4vf
YHzP/&0
</package> L(o#)I>j
Ubm]V{7
</xwork> COA*Q
Qv6-,6<
P:%r3F
7sq15oL
z-N
N(G+
>!MRk[@
V-
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 xSrjN
Q6;bORN
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。 =$SvKzN
V 5D8z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 QjOY1Xze
sB8v:
{t!Pv2y<
S S fNI>
d<RJH
我写的一个用于分页的类,用了泛型了,hoho w@WPp0mny
9AJ"C7
java代码: K57u87=*X?
MU:q`DRr
i} 5M'~F
package com.intokr.util; apjoIO-<
RQ;w$I\
import java.util.List; C#n.hgo>I
tMH2
/** M|fC2[]v B
* 用于分页的类<br> B`)TRt+'.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> \aN7[>R.Q
* *alifdp
* @version 0.01 {Z1KU8tp
* @author cheng {q! :t0X.Y
*/ lvx[C7?
public class Paginator<E> { HCT+.n6
privateint count = 0; // 总记录数 u#UtPF7q
privateint p = 1; // 页编号 .uSVZqJ7
privateint num = 20; // 每页的记录数 _rg*K
privateList<E> results = null; // 结果 ?[;>1+D
De2$:?
/** w=FU:q/
* 结果总数 ^l<!:SS
*/ k}C4:?AT
publicint getCount(){ WO6R04+WV
return count; qM<CBcON
} m48Ab`
{YG qa$+\
publicvoid setCount(int count){ p'A43
this.count = count; wLzV#8>
} VTwQD"oB
|
{Q}:_/q
/** "RTv[n!
* 本结果所在的页码,从1开始 .F N
6/N\
* Z*Rgik
* @return Returns the pageNo. N:;z~`
*/ .03Rp5+v
publicint getP(){ tUt_Q;%yC
return p; p3>Md?e
} D#A6s32a
TKQ^D
/** J9MAnYd)i
* if(p<=0) p=1 Ym.{
{^=
* {eVv%sbq
* @param p `O5427Im
*/ #r/5!*3
publicvoid setP(int p){
h_]*|[g
if(p <= 0) I^HwXp([
p = 1; $z`l{F4eMf
this.p = p; "L!U7|9J
} 'uF75C
B<ue}t
/** `"o{MaFA
* 每页记录数量 virt[5w
*/ (\'$$
publicint getNum(){ zp5ZZcj_
return num; ZL:SJ,C
} 6AoKuT;
IJVzF1vC
/** [] el4.J,
* if(num<1) num=1 lF
t^dl^
*/ ?C- ju8]|
publicvoid setNum(int num){ U1(cBY
if(num < 1) v!$:t<-5N
num = 1; mT #A?C2
this.num = num; E]}_hZU
} t1G__5wp
M|Nh(kvH
/** 9kB R /{
* 获得总页数 A!Tm[oqu
*/ *(qj!U43
publicint getPageNum(){ [H{@<*
return(count - 1) / num + 1; @vB-.XU
} jz]}%O
ahQY-%>
/** 4j8$&~/
* 获得本页的开始编号,为 (p-1)*num+1 rNurzag
*/ 0b['{{X(
publicint getStart(){ %~} ,N
return(p - 1) * num + 1; 3 qJ00A
} xkU8(=
u:Ye`]~o
/** m'N8[ o|h
* @return Returns the results. wa~zb!y<
*/ /]U;7)
publicList<E> getResults(){ (G/(w%#7_
return results; R>]7l!3^1
} z~==7:Os
tfu`_6
public void setResults(List<E> results){ !
,{zDMA
this.results = results; C"$~w3A k
} JU.!<
,iY:#E
public String toString(){ ;9~
WB X"
StringBuilder buff = new StringBuilder >rJ**y
cGR) $:
(); #C~ </R%
buff.append("{"); c*]f#yr?
buff.append("count:").append(count); \.}ZvM$
buff.append(",p:").append(p); %H;}+U]Z
buff.append(",nump:").append(num); _RUL$Ds
buff.append(",results:").append ^*.+4iHx
hlZ{bO'f
(results); IC (:RtJ
buff.append("}"); :U *8S\$
return buff.toString(); n#}~/\P6
} ^#Mp@HK
N/ '
} Srz8sm;
sp
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q
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