Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 xs
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 r&ys?@+G
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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 wz{c;v\J^
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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 pFV~1W:
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分页支持类: I-=Ieq"R9
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java代码: H:
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package com.javaeye.common.util; 2 <@g *
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import java.util.List; (Q&O'ng1
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publicclass PaginationSupport { ~3&hvm[IQ
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publicfinalstaticint PAGESIZE = 30; *=!r|UdB.
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privateint pageSize = PAGESIZE; OEX\]!3_Fm
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privateList items; (9=E5n6o
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privateint totalCount; US"UkY-\
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privateint[] indexes = newint[0]; LU8:]zOY
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privateint startIndex = 0; &Nw|(z&$
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public PaginationSupport(List items, int sTep2W.9
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totalCount){ FFe{=H,=
setPageSize(PAGESIZE); #/8
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setTotalCount(totalCount); :XoR~syT
setItems(items); o*"Q{Xh#Qd
setStartIndex(0); 94]i|2qj*
} _^ic@h3'X~
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public PaginationSupport(List items, int "DH>4Q]
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totalCount, int startIndex){ k,; (`L
setPageSize(PAGESIZE); Kb-m
setTotalCount(totalCount); {x[C\vZsi]
setItems(items); 1mR@Bh
setStartIndex(startIndex); ]2ycJ >w
} lz1cLl
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public PaginationSupport(List items, int k,8^RI07@
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totalCount, int pageSize, int startIndex){ iP:^nt?
setPageSize(pageSize); @`Dh7Q
setTotalCount(totalCount); $fT#Wva-\d
setItems(items); .|TF /b]
setStartIndex(startIndex); \q24E3zS&
} fA[T5<66
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publicList getItems(){ Ir*{IVvej
return items; +qqCk
} "{3|(Qs
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publicvoid setItems(List items){ twK 3
this.items = items; z(2G"}
} IjQgmS~G
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publicint getPageSize(){ jqTK7b
return pageSize; ">S1,rhgS
} v |pHbX
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publicvoid setPageSize(int pageSize){ w{;~
this.pageSize = pageSize; |lu@rN
} =}u?1~V
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publicint getTotalCount(){ y&\t72C$Fi
return totalCount; sb1tQ=u[
} Ox)_7A
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publicvoid setTotalCount(int totalCount){ wAzaxeV=
if(totalCount > 0){
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this.totalCount = totalCount; g2rH"3sC
int count = totalCount / 322-'S3<
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pageSize; ed3wj3@
if(totalCount % pageSize > 0) %\)AT"
count++; Tn(uH17
indexes = newint[count]; /+. m.TF
for(int i = 0; i < count; i++){ 0 N0< 4b
indexes = pageSize * O#>,vf$
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i; }*aj&
} G
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}else{ V%C'@m(/SZ
this.totalCount = 0; ~3-+~y=o~
} ?[WUix;
} jMX|1b
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publicint[] getIndexes(){ 3Q )"
return indexes; U7,.L
} `bn@;7`X
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publicvoid setIndexes(int[] indexes){ fi&>;0?7
this.indexes = indexes; i1]}Q$
} 62G%.'7
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publicint getStartIndex(){ /#L4ec-'
return startIndex; - ku8n%u
} yZNg[KH
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publicvoid setStartIndex(int startIndex){ 3RcnoXX_
if(totalCount <= 0) Z *v`kl
this.startIndex = 0; }>3jHWxLc
elseif(startIndex >= totalCount) at2)%V)
this.startIndex = indexes ?nE9@G5Gc
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[indexes.length - 1]; E>2AG3)
elseif(startIndex < 0) ?#nk}=;g8
this.startIndex = 0; Z7?\ >4V
else{ %j{*`}
this.startIndex = indexes rTJ;s
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[startIndex / pageSize]; 4Yt'I#*
} }?O>.W,/
} W* n|T{n
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publicint getNextIndex(){ `}a-prT<f
int nextIndex = getStartIndex() + gh `_{l
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pageSize; Y
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if(nextIndex >= totalCount) \`-xxhb?e
return getStartIndex(); ;rnhv:Iw
else YhN:t?
return nextIndex; a'*~E?b
} `dl^)4J
qK%#$JgqA
publicint getPreviousIndex(){ X2P8Zq=%a
int previousIndex = getStartIndex() - tdp>vI!
/L2.7`5
pageSize; &k`lbkq
if(previousIndex < 0) Q]dKyMSSA
return0; )<e,- XujY
else ws
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return previousIndex; nS Vr,wU
} 4ZYywD wn
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} 5F]2.<i
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抽象业务类 1.Neg|
java代码: <^ratz!-
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/** 5)->.* G*
* Created on 2005-7-12 X8~?uroq
*/ 3 [O+wVv
package com.javaeye.common.business; Z8f?uF
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import java.io.Serializable; <" 0b8 Z
import java.util.List; P#rS.CIh
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import org.hibernate.Criteria; _~2o
import org.hibernate.HibernateException; f%q ?
import org.hibernate.Session; o,$K=#Iv
import org.hibernate.criterion.DetachedCriteria; Ldy(<cN
import org.hibernate.criterion.Projections; ITz+O=I4R]
import 3XncEdy_
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org.springframework.orm.hibernate3.HibernateCallback; ^t`0ul]c
import y6H`FFqK
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org.springframework.orm.hibernate3.support.HibernateDaoS Su+[Q6oC@
8LY^>.
upport; )d{fDwrx1
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import com.javaeye.common.util.PaginationSupport; F8\JL %
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public abstract class AbstractManager extends UI~ hB4V$]
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HibernateDaoSupport { FB3}M)G>M
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privateboolean cacheQueries = false; JC/nHM
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privateString queryCacheRegion; 1`~.!yd8(
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publicvoid setCacheQueries(boolean F^?DnZs
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cacheQueries){ m+x$LkP
this.cacheQueries = cacheQueries; [&lH[:Y#
} o;OEb
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publicvoid setQueryCacheRegion(String n-OQCz9Xl
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queryCacheRegion){ H6lZ<R{=
this.queryCacheRegion = +.uQToqy
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queryCacheRegion; f`[E^zj
} *De'4r 2
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publicvoid save(finalObject entity){ &@w0c>Y
getHibernateTemplate().save(entity); U[Lr+nKo\
} _KZTY`/*
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publicvoid persist(finalObject entity){ lnK#q.]
getHibernateTemplate().save(entity); .kB!',v\
} YU\k D
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publicvoid update(finalObject entity){ k=O
getHibernateTemplate().update(entity); 7}pg7EF3z
} _s}`ohKvD
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publicvoid delete(finalObject entity){ :4r*Jju<V
getHibernateTemplate().delete(entity); a.a
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} ju1B._48
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publicObject load(finalClass entity, jVqpokWH
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finalSerializable id){ 7j88^59
return getHibernateTemplate().load T9Fe!yVA
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(entity, id); dk 0} q6~
} 2q*wYuc
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publicObject get(finalClass entity, U.Y7]#P:
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finalSerializable id){ U/_hH*N"!
return getHibernateTemplate().get Lb{.}
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(entity, id); $oPc,zS-gL
} `O`MW} c
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publicList findAll(finalClass entity){ e\!Aoky
return getHibernateTemplate().find("from 8isQL
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" + entity.getName()); yet~
} yD@1H(yM
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publicList findByNamedQuery(finalString Vlge*4q
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namedQuery){ X8wtdd]64
return getHibernateTemplate KN>h*eze
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().findByNamedQuery(namedQuery); }y vH)q
} I+31:#d
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publicList findByNamedQuery(finalString query, " ]OROJGa
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finalObject parameter){ I1I-,~hO
return getHibernateTemplate 5Vai0Qfcu:
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().findByNamedQuery(query, parameter); *,~L_)vWO
} 4um^7Ns)7
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publicList findByNamedQuery(finalString query, ?]o(cz
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finalObject[] parameters){ EV7lgKM^
return getHibernateTemplate &xp]9$
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().findByNamedQuery(query, parameters); E'NS$,h
} 2jxIr-a1G
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publicList find(finalString query){ X#zp,7j?
return getHibernateTemplate().find U+C^"[B
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(query);
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} ^;tB,7:*V
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publicList find(finalString query, finalObject q([{WZ:6Oq
=^ \?{oV
parameter){ oxdX2"WwU
return getHibernateTemplate().find B{p74
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(query, parameter); >8b%*f8R
} d8U<V<H<
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public PaginationSupport findPageByCriteria ~O]{m,)n
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(final DetachedCriteria detachedCriteria){ {'z$5<|
return findPageByCriteria A(n#k&W1fZ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); s+z 5"3'n
} CxSh.$l
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public PaginationSupport findPageByCriteria L\t_zf_0
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(final DetachedCriteria detachedCriteria, finalint ;cZp$
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startIndex){ ) .KMZ]
return findPageByCriteria ia3!&rZ
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(detachedCriteria, PaginationSupport.PAGESIZE, USS%T<Vk
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startIndex); E0yx
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} i0J`{PbI
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public PaginationSupport findPageByCriteria _pDfPLlY&
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(final DetachedCriteria detachedCriteria, finalint %(W8WLz}
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pageSize, M{)&SNI*C
finalint startIndex){ j%Xa8$
return(PaginationSupport) "a3?m)
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getHibernateTemplate().execute(new HibernateCallback(){ R/kJUl6HEl
publicObject doInHibernate /lh1sHgD
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(Session session)throws HibernateException { nh"dPE7^
Criteria criteria = E.+%b;Eqe
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detachedCriteria.getExecutableCriteria(session); O.-n&U9
int totalCount = !2^~ar{2
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((Integer) criteria.setProjection(Projections.rowCount TdT`Vf
5 jUy[w @
()).uniqueResult()).intValue(); scYqU7$%T
criteria.setProjection 6:6A"A
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(null); 08D:2 z1z
List items = M_>kefr
>/lB%<$/
criteria.setFirstResult(startIndex).setMaxResults *'-t_F';
^E:-Uy
(pageSize).list(); }`%ks
PaginationSupport ps = /y6f~F
cza_LO(
new PaginationSupport(items, totalCount, pageSize, 2eA.04F
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startIndex); !pkIaCxs
return ps; S^|U"
} dv+ZxP%g
}, true); R!lug;u#
} XgM&0lVT
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public List findAllByCriteria(final EWgJ"WTF
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DetachedCriteria detachedCriteria){ E*wG5]at
return(List) getHibernateTemplate c))?9H
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().execute(new HibernateCallback(){ "Dc\w@`E 0
publicObject doInHibernate Cl-P6NlR".
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(Session session)throws HibernateException { yT5OFD|T
Criteria criteria = yU4mS;GX
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detachedCriteria.getExecutableCriteria(session); 9V[}#(f$
return criteria.list(); gIusp917
} 0@{0#W3R
}, true); NQX?&9L`r
} LME&qKe5
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public int getCountByCriteria(final 5]upfC6
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DetachedCriteria detachedCriteria){ nE*S3
Integer count = (Integer) p<#aXs jy
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getHibernateTemplate().execute(new HibernateCallback(){ !{+.)%d'g
publicObject doInHibernate '`.-75T
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(Session session)throws HibernateException { 32?'jRN(ue
Criteria criteria = / o
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detachedCriteria.getExecutableCriteria(session); 19c_=$mV
return &qWB\m
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criteria.setProjection(Projections.rowCount *hJWuMfY,
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()).uniqueResult(); ,aGIq. *v
} *78c2`)[
}, true); m-ibS:
return count.intValue(); UZrEFpi
} O(!;7v}
} h6^|f%\w*i
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用户在web层构造查询条件detachedCriteria,和可选的 >1;jBx>Qy%
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (dD7"zQ
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PaginationSupport的实例ps。 unew
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ps.getItems()得到已分页好的结果集 g?Nk-cg
ps.getIndexes()得到分页索引的数组 #asi%&3pP
ps.getTotalCount()得到总结果数 }2"W0ZdWD
ps.getStartIndex()当前分页索引 R=D}([pi
ps.getNextIndex()下一页索引 oH?:(S(
ps.getPreviousIndex()上一页索引 u)I\R\N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 B5vLV@>]
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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 TK[[6IB
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一下代码重构了。 `[(XZhN
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我把原本我的做法也提供出来供大家讨论吧: 1Q!^*D
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首先,为了实现分页查询,我封装了一个Page类: !#W>x49}
java代码: 0F%8d@Y2
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/*Created on 2005-4-14*/ zPqJeYK
package org.flyware.util.page; M9BEG6E9
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/** w43b=7
* @author Joa 4:NMZ `~
* ^Cp2#d*
*/ N\B&|;-V
publicclass Page { Xb>SA|6[|
H1B%}G*Ir-
/** imply if the page has previous page */ fuv{2[NV
privateboolean hasPrePage; d;0]xG?%=
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t
/** imply if the page has next page */ x[0hY0 ?[M
privateboolean hasNextPage; '@hUmrl
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/** the number of every page */ tlUh8os
privateint everyPage; 7<MEM NYX
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/** the total page number */ D:bmq93PC
privateint totalPage; gDLS)4^w
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/** the number of current page */ nb=mY&q}~
privateint currentPage; 6)*fr'P
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/** the begin index of the records by the current 9?O8j1F
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query */ +
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privateint beginIndex; *->*p35
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/** The default constructor */ 0Atha>w^o~
public Page(){ gveJ1P
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} `14@dk
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/** construct the page by everyPage y,|2hrj/0E
* @param everyPage s9CmR]C
* */ W-#DEU 7_
public Page(int everyPage){ wzju)q S
this.everyPage = everyPage; XF)N_}X^
} 6d;}mhH
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/** The whole constructor */ cpP}NJb0;%
public Page(boolean hasPrePage, boolean hasNextPage, S9}I
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int everyPage, int totalPage, z=U+FHdh/-
int currentPage, int beginIndex){ 6JZ>&HA
this.hasPrePage = hasPrePage; E9j<+Ik
this.hasNextPage = hasNextPage; -_5Dk'R#`
this.everyPage = everyPage; ZM -P
this.totalPage = totalPage; 5Ex[}y9L`
this.currentPage = currentPage; JFX}))7
this.beginIndex = beginIndex; ~^a>C
} T[1iZ
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/** _xePh
* @return 1q-;+Pd;
* Returns the beginIndex. T\.(e*hC
*/ QCZ88\jX[
publicint getBeginIndex(){ GLecBF+>F
return beginIndex;
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} 4>V@+#Ec5
g_c@Kyf
/** "Ux(nt
* @param beginIndex *izCXfW7
* The beginIndex to set. /fb}]e]N
*/ |"9&F
publicvoid setBeginIndex(int beginIndex){ z/4<x?}+hE
this.beginIndex = beginIndex; ^0| :
} G-9i
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/** lPxhqF5pP
* @return 0*5Jq#5
* Returns the currentPage. J~WT;s
*/ +%\Ci!%b
publicint getCurrentPage(){ {v]L|e%{
return currentPage; W7uX
} 5U7,,oyh
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/** .W~XX
* @param currentPage K
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* The currentPage to set. z*jaA;#
*/ ;y\/7E
publicvoid setCurrentPage(int currentPage){ )u{]rb[
this.currentPage = currentPage; |=YK2};
} vi^YtA
_";w*lg}
/** PVlCj
* @return o5&b'WUJ=
* Returns the everyPage. :
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*/ .tG3g:
publicint getEveryPage(){ t{iRCj
return everyPage; Gn^lF7yE
} K% FK
&t8,326;
/** < r~hU*u
* @param everyPage =Mwuhk|*
* The everyPage to set. q:)PfP+
*/ KZ[TW,Gw
publicvoid setEveryPage(int everyPage){ |s/N?/qi
this.everyPage = everyPage; Nkj$6(N=zJ
} U"8Hw@
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/** 0~BaQ,
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* @return 7O*Sg2B
* Returns the hasNextPage. Cn5"zDK$
*/ ;E
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publicboolean getHasNextPage(){ fK=0?]s}I
return hasNextPage; qy pF}Pw
} *s 4Ym
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/** %/e'6g<
* @param hasNextPage AYY(<b
* The hasNextPage to set. | 8mWR=9fs
*/ akr2Os
publicvoid setHasNextPage(boolean hasNextPage){ G?Gf,{#K
this.hasNextPage = hasNextPage; +8Q @R)3
} CtN\-E-
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/** 7Ji'7$
* @return )C?H m^#
* Returns the hasPrePage. ej_u):G*
*/ %$zak@3%'
publicboolean getHasPrePage(){ ;5X~"#%U_
return hasPrePage; AFL'Ox]0
} ]>[TF'pIAx
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/** vS~tr sI
* @param hasPrePage LWqKSNE;
* The hasPrePage to set. AcnY6:3Y|
*/ YFu,<8"swe
publicvoid setHasPrePage(boolean hasPrePage){ bi}aVtG~z
this.hasPrePage = hasPrePage; dF51_Kk
} ~;$QSO\2h
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/** LqD7SJ}/f
* @return Returns the totalPage. ?Ybq]J\q
* RYvcuA)
*/ "ADI.
publicint getTotalPage(){
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return totalPage; T;B FO5G@
} L bJf5xdi
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/** e)?}2
* @param totalPage +$L}B-F
* The totalPage to set. l:@=9Fp>
*/ OHAU@*[lM
publicvoid setTotalPage(int totalPage){ I$sXbM;z=
this.totalPage = totalPage; ~v\
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} }xr0m+/
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} O&/nBHu\
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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 %-fXa2
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个PageUtil,负责对Page对象进行构造: {_(R?V]w,
java代码: Xa>'DO2
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/*Created on 2005-4-14*/ ;&|I/MVm
package org.flyware.util.page; -`Z!p
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import org.apache.commons.logging.Log; 0sw;h.VY
import org.apache.commons.logging.LogFactory; B2$cY;LH
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/** :!t4.ko
* @author Joa i^:#*Q-co
* a8)2I~j
*/ c oZK
publicclass PageUtil { ,aezMbg
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privatestaticfinal Log logger = LogFactory.getLog w6>P[oW
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(PageUtil.class); ;lE=7[UJ3X
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/** u!~kmIa4
* Use the origin page to create a new page O{c#&/ .K
* @param page Pw]+6
* @param totalRecords _oa*E2VN
* @return 2K/t[.8
*/ {7oPDP
publicstatic Page createPage(Page page, int o8:9Yjs
#w5%^HwO
totalRecords){ <tZtt9j_
return createPage(page.getEveryPage(), 5#|&&$)
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page.getCurrentPage(), totalRecords); /0k'w%V{n
} Jo[&y,
!jB}}&Ii
/** B+Qo{-
* the basic page utils not including exception !.# g
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Ol.
handler `2+TN
* @param everyPage 32 j){[PL3
* @param currentPage 0 5?`W&:9
* @param totalRecords /YPG_,lRA
* @return page 8VU(+%X
*/ WQCnkP
publicstatic Page createPage(int everyPage, int &m36h`tM
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currentPage, int totalRecords){ E[ -yfP~[
everyPage = getEveryPage(everyPage); C%<Dq0j
currentPage = getCurrentPage(currentPage); aLLI\3
int beginIndex = getBeginIndex(everyPage, uIO?4\s&G
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currentPage); ]QY-LO(
int totalPage = getTotalPage(everyPage, 6||%T$_;}
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totalRecords); R=Ig !s9
boolean hasNextPage = hasNextPage(currentPage, 80%"2kG
x{!+4W;S
totalPage); v h)CB8
boolean hasPrePage = hasPrePage(currentPage); $_'<kH-eP
o@
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returnnew Page(hasPrePage, hasNextPage, ->{\7|^
everyPage, totalPage, #%$@[4"V
currentPage, YVF@v-v-,
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beginIndex); f$}g'r zl
} KMfIp:~
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privatestaticint getEveryPage(int everyPage){ )D+eWo
return everyPage == 0 ? 10 : everyPage; )xg8#M=K
} m7A3i<6p
\N|}V.r
privatestaticint getCurrentPage(int currentPage){ hB>FJZQ_
return currentPage == 0 ? 1 : currentPage; e 5(|9*t
} 8 *m,#
z\,
lPwB2
privatestaticint getBeginIndex(int everyPage, int i,RbIZnJ
suaP'0
currentPage){ KDP&I J
return(currentPage - 1) * everyPage; %>zG;4
} &l`_D?{<#
:ba4E[@
privatestaticint getTotalPage(int everyPage, int I
WT|dA >
Oel%lY}m3
totalRecords){ P^q!Pye
int totalPage = 0; 2Nm{.Y
P9`CW
if(totalRecords % everyPage == 0) c?c"|.-<p
totalPage = totalRecords / everyPage; YGyw^$.w
else -`spu)
totalPage = totalRecords / everyPage + 1 ; fK(:vwh
j)Q}5M
return totalPage; * >NML]#0
} {=!BzNMj
WT,dTn;W
privatestaticboolean hasPrePage(int currentPage){ -zt*C&)b
return currentPage == 1 ? false : true; %F-yFN"
} $_HyE%F#
3S>rc0]6
privatestaticboolean hasNextPage(int currentPage, qgWsf-di=
$LU|wW
int totalPage){ Mz)
r'
return currentPage == totalPage || totalPage == +WR'\15u
:zfMRg
0 ? false : true; RcR-sbR
} K-.%1d@$y
Q0ezeo
0iMfyW:
} C^]UK
PK{FQ3b2{
HDE5Mg "
]d|M@v~c4
R5},E
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。 O#8lJ%?
CAA3-"Cwi
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!(w. G
7oL:C
做法如下: (o\D=!a
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1]8Hpd
b'/:e#F
的信息,和一个结果集List: #~|esr/wf
java代码: Mac :E__G
`09[25?
eXLdb-
/*Created on 2005-6-13*/ &=Y%4vq
package com.adt.bo; 5Tidb$L;Du
fo9V&NE
import java.util.List; `J{{E,y
@
h,fahbH-
import org.flyware.util.page.Page; }U%E-:
`B3YP1
/** o/RGz PR
* @author Joa ^#w9!I{4.
*/ S!R(ae^}
publicclass Result {
`X=[ m>
s9u7zqCF
private Page page; (r<F@)J
& )-fC
private List content; C}o^p"M*B3
*li5/=UC5*
/** +&1#ob"6lq
* The default constructor -)ri,v{:c
*/ ']X0g{%
public Result(){ 'Ze&
LQ
super(); bg|=)sw4
} \w$e|[~
!83 N#Y_Mz
/** UrS%t>6k
* The constructor using fields WL\*g] K4
* PDh!B_+
* @param page [S.zWPX9{
* @param content bGj<Dojl
*/ ?U*s H2F
public Result(Page page, List content){ ufA0H
J)Yg
this.page = page; 7Z81+I|&8
this.content = content; G1,u{d-_
} |;C;d"JC2
THwq~c'
/** Pn}oSCo
* @return Returns the content. Qeq=4Nq
*/ RHt~:D3*
publicList getContent(){ BJZGQrsz
return content; T(kG"dz
} p|)j{nc
gF~
}
/** 0}Qd
* @return Returns the page. fAT
M?
*/ |'L$ogt6
public Page getPage(){ $A: ?o?"7}
return page; 3-![%u
} *+ O
o-AAx#@
/** j6rwlwN
* @param content {\k:?w4
* The content to set. dpcv'cRfw
*/ r?Pk}Q
public void setContent(List content){ $! UEpQ
this.content = content; p1\EC#Q
} <2w41QZX
UzkX;UA
/** Hn?v/3
* @param page xl@
* The page to set. &!8u4*K5j
*/ ?)/H8n
publicvoid setPage(Page page){ 4e|(= W`
this.page = page; }M(XHw
} _^w^tfH]
} zhACNz4tJ
7(zY:9|(
SciEHI#
]=5D98B
~uO9>(?D
2. 编写业务逻辑接口,并实现它(UserManager, m\|ie8
kQtnT7
UserManagerImpl) I9jzR~T
java代码: $K~ t'wr
/}-LaiS
&?SU3@3|
/*Created on 2005-7-15*/ O#b%&s"o
package com.adt.service; [PU0!W;
!~f!O"n)3r
import net.sf.hibernate.HibernateException; #_fL[j&
?OWJ UmQ
import org.flyware.util.page.Page; TSP#.QY
|?uUw$oh
import com.adt.bo.Result; d?OsVT;U
{(`xA,El
/** '.tg\]|
* @author Joa H?'t>JX
*/ VQ`a-DL
publicinterface UserManager { 3C;nC?]K
JwmH_nJ(
public Result listUser(Page page)throws 4kf8Am(
_i1x\Z~
N
HibernateException; !bIhw}^C*
?{-y? %y
} Lc13PTz>>g
oyo
V1jO
Z|$OPMLX
UxVxnJ_
+S}/6dg
java代码: ^y&sKO
X\LiV{c
| D,->k
/*Created on 2005-7-15*/ \MFjb IL
package com.adt.service.impl; 1mz72K
By}>h6`[
import java.util.List; BjCg!6`XF
x]jJ
import net.sf.hibernate.HibernateException; X/`M'8v.%
*`wgqin
import org.flyware.util.page.Page; A;C)#Q/
import org.flyware.util.page.PageUtil; G8!* &vR/
c7(Lk"G8
import com.adt.bo.Result; \TXCq@
import com.adt.dao.UserDAO; #R3|nL
import com.adt.exception.ObjectNotFoundException; $2gZpO|
import com.adt.service.UserManager; =LMM]'no,
97L#3L6t
/** ygfUy
* @author Joa R8<P}mv
*/ ;R{ffS6
publicclass UserManagerImpl implements UserManager { "iTi+UZxe
jr=erVHK
private UserDAO userDAO; f8836<c
@t?uhT*Z=
/** Eh&HN-&
* @param userDAO The userDAO to set. H)l7:a
*/ I Z{DR
publicvoid setUserDAO(UserDAO userDAO){ l^E)XWd
this.userDAO = userDAO; GbN|!,X1m
} YB'BAX<lI
xnD"LK
/* (non-Javadoc) :f5"w+
* @see com.adt.service.UserManager#listUser [}t^+^/
mR6hnKa_53
(org.flyware.util.page.Page) ]<IK0
*/ $:SSm$k
public Result listUser(Page page)throws U/3<p8
tEHgQto
HibernateException, ObjectNotFoundException { Ub-q0[6
int totalRecords = userDAO.getUserCount(); 'PVxc%[
if(totalRecords == 0) eJwHeG
throw new ObjectNotFoundException *3]_Huw<
vX/("[
("userNotExist"); 8xN+LL'T{
page = PageUtil.createPage(page, totalRecords); ]:r6
List users = userDAO.getUserByPage(page); rGb<7b%
returnnew Result(page, users); tDIQ=
} d/Y#oVI
}MXC0Z~si
} A
2Rp
X(*MHBd
c
1o8
6@;
P
#:LI,t
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;_Z[' %
$I }k>F
询,接下来编写UserDAO的代码: DZE@C^0%
3. UserDAO 和 UserDAOImpl: ;o-c.-!F
java代码: T1_>qnSz
A$ Ok^
T.?}iz=ZEq
/*Created on 2005-7-15*/ 9B<aYp)
package com.adt.dao; KoKd.%
G=l-S\0@
import java.util.List; YecV+K'p:
XlDN)b5v{
import org.flyware.util.page.Page; `4kVe= {
{IA3`y~
import net.sf.hibernate.HibernateException; ::R5F4
\qj(`0HG
/** Uon^z?0A
* @author Joa ?0J&U4
*/ c$#7Kp4
publicinterface UserDAO extends BaseDAO { -#<AbT
Cu&y',ee~
publicList getUserByName(String name)throws zVyMmw\
C
5
xsh
HibernateException; d !=AS
?3=y]Vb+
publicint getUserCount()throws HibernateException; tqXr6+!Q
^R7|x+
publicList getUserByPage(Page page)throws ^9fY%98
%v)O!HC}
HibernateException; Vc*"Q8aZ~
-fCR^`UOS
} ^e\H V4s
)
o`ep{<t
g`\5!R1
`b?o%5V2x
R;3nL[{U
java代码: ^bG91"0A
!@3"vd{^
5-?*Boi>i
/*Created on 2005-7-15*/ My<.^~
package com.adt.dao.impl; 2D)B%nM[
'B yB1NL
import java.util.List; #bCQEhCy
1=z6m7@'-
import org.flyware.util.page.Page; 4U>g0
^bk:g}o
import net.sf.hibernate.HibernateException; l#bE_PD;
import net.sf.hibernate.Query; BHN EP |=
MmQ"z_v
import com.adt.dao.UserDAO; k$3Iv"gbx
Cm%|hk>fQ
/** ,4--3 MU
* @author Joa GW,RE\Q:
*/ <\`qRz0/
public class UserDAOImpl extends BaseDAOHibernateImpl {L/hhKT
F_ -}GN%
implements UserDAO { Xb2.t^
]f
7.FD16
/* (non-Javadoc) Tnoy#w}Ve
* @see com.adt.dao.UserDAO#getUserByName 7&&3@96<*#
tE WolO[\
(java.lang.String) 7A"v:e
*/ ,s`4k?y
publicList getUserByName(String name)throws 4@r76v}{
G3dA`3
HibernateException { 4t,f$zk
String querySentence = "FROM user in class )m_q2xV
|'qvq/#^
com.adt.po.User WHERE user.name=:name"; /(8"9Sfm
Query query = getSession().createQuery ~CuJ$(9Y
R4vf
(querySentence); YHzP/&0
query.setParameter("name", name); =*{Ii]D
return query.list(); COA*Q
} Qv6-,6<
Qo\?(EM
/* (non-Javadoc) "</A)y&
* @see com.adt.dao.UserDAO#getUserCount() T^Ol=QCu
*/ #
11<=3Yj
publicint getUserCount()throws HibernateException {
*I.eCMDa
int count = 0; [\-)c[/
String querySentence = "SELECT count(*) FROM `*",_RO;
Y1G/1Z# 2
user in class com.adt.po.User"; (f;.`W
Query query = getSession().createQuery p^k*[3$0
Zu/w[*;M
(querySentence); )F+wk"`+6
count = ((Integer)query.iterate().next p|g7Z
G@P+M1c
()).intValue(); m:6*4_!
return count; \+j:d9?
} ),J6:O&
+CN!3(r
/* (non-Javadoc) ~9Qd83`UH
* @see com.adt.dao.UserDAO#getUserByPage M>d^.n
4JRQ=T|P7I
(org.flyware.util.page.Page) zZ 94_8b
*/ K-[;w$np0
publicList getUserByPage(Page page)throws |7QSr!{_
bbT1p:RF
HibernateException { 0BQ{ZT-Kh
String querySentence = "FROM user in class >i"WKd=
\aN7[>R.Q
com.adt.po.User"; *alifdp
Query query = getSession().createQuery {Z1KU8tp
{q! :t0X.Y
(querySentence); dU-nE5
query.setFirstResult(page.getBeginIndex()) zX]l$Q+
.setMaxResults(page.getEveryPage()); .d6b?t
return query.list(); 7%Ou6P$^fr
} ?x/Lb*a^
UCj{
&
} fp}5QUm-
QmMA]Q
X?o6=)SC|
7{\6EC}d[&
ZCuo YE$g
至此,一个完整的分页程序完成。前台的只需要调用 TE:|w
Xe
kB.CeG]tk
userManager.listUser(page)即可得到一个Page对象和结果集对象 2!R+5^Iy
2~R%_r+<
的综合体,而传入的参数page对象则可以由前台传入,如果用 5Q\ hd*+g
wjXv{EsMq
webwork,甚至可以直接在配置文件中指定。 #v; :K8
=IKgi-l*
下面给出一个webwork调用示例: qu&p)*M5
java代码: $]rC-K:Z
NQA2usb
=]S,p7* 7
/*Created on 2005-6-17*/ \-SC-c
package com.adt.action.user; %C_c%3d
kbo9nY1k
g
import java.util.List; &?}A/(#
nk;^sq4M:
import org.apache.commons.logging.Log; a$\Bt_
import org.apache.commons.logging.LogFactory; H@b4(6
import org.flyware.util.page.Page; nok-![
Xck`"RU<xA
import com.adt.bo.Result; =;(L$:l~
import com.adt.service.UserService; ~E/=nv$
import com.opensymphony.xwork.Action; v#EFklOP
^7a@?|,q8
/** k136n#KN1
* @author Joa Ri\\Yb
*/ "L!U7|9J
publicclass ListUser implementsAction{ 'uF75C
B<ue}t
privatestaticfinal Log logger = LogFactory.getLog Sp2DpGs~
3 .K #,
(ListUser.class); >.I9S{7
'S|7<<>4k
private UserService userService; +,cd$,18
ra2{8 x
private Page page; zI\+]U'
U9K'O !i>
privateList users; 4)8e0L*[B?
HYL['B?Wid
/* 8/T,{J\
* (non-Javadoc) PEg]z
* 4Y1dkg1y
* @see com.opensymphony.xwork.Action#execute() ZtmaV27s/
*/ J~n|5*cz
publicString execute()throwsException{ W23Q>x&S
Result result = userService.listUser(page); Te`@{>
page = result.getPage(); 3.1%L"r[)
users = result.getContent(); )7X$um
return SUCCESS; RB6Q>3g
} _zJ /z
_90<*{bt.
/** `<kB/T
* @return Returns the page. Lz!JLiMEET
*/ @|5B}%!
public Page getPage(){ 1xu~@v60
return page; ]s!id[j
} 94^b"hU
8]oolA:^4s
/** R:3=!zav
* @return Returns the users. L|L|liWd
*/ #kh:GAp]
publicList getUsers(){ p<z eaf0W
return users; 5S,Kq35$(
} )8oN$20
t{QQ;'
/** O#t[YP
* @param page dPbn[*:
* The page to set. ~9xkiu5~
*/ ^d@2Y0hH
publicvoid setPage(Page page){ tRO=k34
this.page = page; Zw _aeJ
} KCAV
'MBXk2?b
/** c*]f#yr?
* @param users g cB
hEw
* The users to set. ^b|I^TN0
*/ h"/'H)G7_&
publicvoid setUsers(List users){
2W`WOBz
this.users = users; Xs# _AX
} JWYe~
J@"UFL'^
/** ,RM8D)m\
* @param userService \I-e{'h
* The userService to set. G.^)5!By
*/ QqRF?%7q"q
publicvoid setUserService(UserService userService){ cTS.yN({G
this.userService = userService; \#WWJh"W
} jvAjnh#
} ;]b4O4C\
DA04llX~
5!cp^[rGL
Sc#3<nVg
@}:E{J#g
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 4<Nd5T
:WX
OD
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 u|T]Ne
/zb/am1#
么只需要: (z.n9lkfi
java代码: ^)I}#
G;iH.rCH
KO%$
<?xml version="1.0"?> W$2\GPJt
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2K{'F1"RM
Kh[l};/F
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~,E }^
dvqg H
1.0.dtd"> $v[mIR
S89j:KRXH%
<xwork> 1G"ohosmF
*S"RU~1_
<package name="user" extends="webwork- dP(.l}O
%8h=_(X\7
interceptors"> <7SE|
I.G[|[. Do
<!-- The default interceptor stack name HA,8O[jon
RgUQ:
--> ~[dL:=?c
<default-interceptor-ref }A,!|m4
KvEv0L<ky
name="myDefaultWebStack"/> ZSW@,Ti
c"-X:m"
<action name="listUser" XzSl"U PYH
@eeI4Jz
class="com.adt.action.user.ListUser"> Q{?\qCrrYl
<param dNNXMQ0"
D)?%kNeA
name="page.everyPage">10</param> \#LDX,=
<result rab$[?]
fP5i3[T
name="success">/user/user_list.jsp</result> 5>+@.hPX
</action> TfT^.p*
t&EizH$
</package> D!!
B4zt
yYYP;N?g4k
</xwork> KXDnhVf
0%%U7GFB5
nW"O+s3
VevG 64o
K-)!d$$
gd]S;<Jh
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 HcJ!(
o$l8"Uv
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。 =0]K(p,
egSs=\
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 L.yM"
UPr&
`kaJ
d~r A`!s7`
.?5
~zK
036m\7+Qj
我写的一个用于分页的类,用了泛型了,hoho utuWFAGn A
(lS[a
java代码: ZD'mwj+K
`h'l"3l
/g!ZU2&l
package com.intokr.util; K>e-IxA);0
#n{4f1TZ
import java.util.List; @s
cn ?t
k{#k:
/** v]EZYEXFL)
* 用于分页的类<br> $Wj{B@k
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _AX,}9
* 3N-
'{c6]U
* @version 0.01 }T(=tfv@
* @author cheng ~!~i_L\V
*/ u&uFXOc'
public class Paginator<E> { `ovMfL.u
privateint count = 0; // 总记录数 KJ32L
privateint p = 1; // 页编号 Q"D
privateint num = 20; // 每页的记录数 j0~am,yZ
privateList<E> results = null; // 结果 jT$J~MpHh
} % Ie
/** 89^g$ ac
* 结果总数 pTG[F
*/ ^.iRU'{
publicint getCount(){ @ Do.Wgt
return count; O50<h O]l
} _b&26!gl
1uN;JN
`_
publicvoid setCount(int count){ J^yqu{
this.count = count; X,aRL6>r
} 6`Y:f[VB
}Vob)r{R@
/** HVoPJ!K3
* 本结果所在的页码,从1开始 4)D~S4{E5
*
K];]
* @return Returns the pageNo. F"k`PF*b
*/ &8l?$7S"_/
publicint getP(){ aReJ@
return p; 0C%IdV%CU
} lSaX!${R'T
yc?L
OW0
/** #J3o~,t<
* if(p<=0) p=1 \P+^BG!
* ]
&" `
* @param p $%\6"P/64
*/ qMVuFwPhi
publicvoid setP(int p){ yOQae m^O
if(p <= 0) gAorb\iJ
p = 1; iYvzZ7
8f
this.p = p; %m f)BC
} C.:S@{sK
M^Z=~512g
/** Qx,#Hj
* 每页记录数量 G4:\6fu
*/ z"yW):X
publicint getNum(){ '}(>s%~
return num; Miw=2F
} !ITM:%
c}n66qJF5
/** A|1xK90^XT
* if(num<1) num=1 KCbJ^Rln
*/ >'q]ypA1
publicvoid setNum(int num){ L-E?1qhP>
if(num < 1) Z3c\}HLY
num = 1; _[z)%`kay
this.num = num; .rO~a.kG
} R,78}7B
qOy(dG g
/** N[3Y~HX!q
* 获得总页数 us?q^>u
*/ DoFe:+_U3
publicint getPageNum(){ Z]Udx
return(count - 1) / num + 1; *,CJ 3<>
} $`7Fk%#+e
+g7]ga
/** ?+7~E8
* 获得本页的开始编号,为 (p-1)*num+1 S@3`H8 [
*/ 4(P<'FK $
publicint getStart(){ F*#!hWtb
return(p - 1) * num + 1; CSoVB[vS
} KzV|::S^
z(Uz<*h8
/** @]#[TbNo
* @return Returns the results. 0aY\(@
*/ nTo?~=b
publicList<E> getResults(){ IFew3!{\
return results; qF$y
p>|#
} QOUyD;0IW
$$.q6
public void setResults(List<E> results){ ,.(:b82$
this.results = results; BC_<1
c
} R\3v=PR[
;}f {o^ ]'
public String toString(){ 1+-Go}I
StringBuilder buff = new StringBuilder Kgi`@`
t^K Qv~
(); iR9duP+
buff.append("{"); xg,
9~f[
buff.append("count:").append(count); ,N,@9p
buff.append(",p:").append(p); 24 [cU
buff.append(",nump:").append(num); J`0dF<<{[y
buff.append(",results:").append ZDzG8E0Sq
]?T^tJ
(results); V6d,}Z+"z'
buff.append("}"); >f Hu
return buff.toString(); 6l2O>V
} QQN6\(;-
PR!0=E*}
}
+ug2p;<B
k=kkF"
rp<~=X