Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z&[_8Y5j
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4o``t]
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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 |
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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 NpN-''B\
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分页支持类: R!2oj_
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java代码: ]UFbG40Zo
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{
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package com.javaeye.common.util; 71(C@/J
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import java.util.List; \2huDNW&
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publicclass PaginationSupport { (>usa||
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publicfinalstaticint PAGESIZE = 30; TeXt'G=M
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privateint pageSize = PAGESIZE; n,vs(ZL:
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privateList items; uFl19
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privateint totalCount; IyJHKDFk
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privateint[] indexes = newint[0]; ~]LkQQ'
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privateint startIndex = 0; 6tKCY(#oO+
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public PaginationSupport(List items, int h-+GS%
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totalCount){ E
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setPageSize(PAGESIZE); #BLmT-cl
setTotalCount(totalCount); 75?z" i
setItems(items); H\!p%Y
setStartIndex(0); m. EIMuj
} dw"{inMf
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public PaginationSupport(List items, int SG@-b(
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totalCount, int startIndex){ ~+OAAkJ9
setPageSize(PAGESIZE); G>f2E49BXt
setTotalCount(totalCount); XjINRC8^4
setItems(items); >uR0Xs;V
setStartIndex(startIndex); =QQTHL{3
} &U7INUL
& Y Y^Bd#
public PaginationSupport(List items, int BfUM+RC%5
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totalCount, int pageSize, int startIndex){ Tc.k0n%W:b
setPageSize(pageSize); ~8l(,N0
setTotalCount(totalCount); ) u
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setItems(items); q"C(`S.@
setStartIndex(startIndex); i$CN{c*
} 7>,(QHl
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publicList getItems(){ u zgQ_
return items; JDp{d c
} M|DVFC
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publicvoid setItems(List items){ 3 jR I@
this.items = items; K0xka[x=(
} YggeKN
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publicint getPageSize(){ r=74'g
return pageSize; (u:^4,Z
} 'ugc=-0pd
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publicvoid setPageSize(int pageSize){ +0Z,#b
this.pageSize = pageSize; |f IIfYE
} t]14bf$*Q
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publicint getTotalCount(){ ZlG|U]mM5
return totalCount; Ef~Ar@4fA
} Svqj@@_f
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publicvoid setTotalCount(int totalCount){ mi]bS
if(totalCount > 0){ p()#+Xy
this.totalCount = totalCount; d":GsI?3
int count = totalCount / U_[<,JE
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pageSize; aP&bW))CI
if(totalCount % pageSize > 0) 8gn12._x
count++; d.3cd40Q
indexes = newint[count]; Q/zlU@
for(int i = 0; i < count; i++){ ;eY.4/*R
indexes = pageSize * !> 2kH
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i; 0 *^>/*
} EJ@&vuDd$
}else{ J1UG},-h
this.totalCount = 0; 50jZu'z:
} )Gm,%[?2C
} $~c
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publicint[] getIndexes(){ B9(@.
return indexes; JEh(A=Eu>
} l' mdj!{&
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publicvoid setIndexes(int[] indexes){ ,7h0y
this.indexes = indexes; "zZZ h
} bGtS! 'I
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publicint getStartIndex(){ z)Gd3C
return startIndex; DmtCEKa
} SE<?l
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publicvoid setStartIndex(int startIndex){ Mj<T+Ohz
if(totalCount <= 0) 67b
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this.startIndex = 0; Q5xQ5Le
elseif(startIndex >= totalCount) Ek6z[G`
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this.startIndex = indexes (|9t+KP
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[indexes.length - 1]; [JVEKc ym
elseif(startIndex < 0) ORx6r=zg
this.startIndex = 0; qd<-{
else{ Lvd es.0|
this.startIndex = indexes cNl NJ
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[startIndex / pageSize]; E< Y!BT[X
} q>rDxmP<
} 6m%#cP
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publicint getNextIndex(){ S7
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int nextIndex = getStartIndex() + Zk ] /m
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pageSize; H! P$p-*.
if(nextIndex >= totalCount) \k
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return getStartIndex(); H):(8/>(
else %WF]mF T_
return nextIndex; z5p5=KOb
} _J"fgxW
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publicint getPreviousIndex(){ 6o
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int previousIndex = getStartIndex() - PC!g?6J
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pageSize; aqEmF
if(previousIndex < 0) {/}%[cY=
return0; ey@ccc*sZ9
else ]{|
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return previousIndex; |/;;uK,y
} Marx=cNj
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} GIZw/L7Yb
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抽象业务类 H~
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java代码: %<0'xJ%%Q
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/** FBxg^g%PB@
* Created on 2005-7-12 MfZamu5+F
*/ $p|Im,
package com.javaeye.common.business; ^Na3VP
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import java.io.Serializable; '*B%&QC-
import java.util.List; ON9L+"vqv0
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import org.hibernate.Criteria; Rt>mAU$}
import org.hibernate.HibernateException; goe%'k,
import org.hibernate.Session; .*edaDi
import org.hibernate.criterion.DetachedCriteria; #>M^BOR8
import org.hibernate.criterion.Projections; xzHb+1+p
import )FN\jo!!.
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org.springframework.orm.hibernate3.HibernateCallback; Z!-V&H.
import lVCnu>8
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org.springframework.orm.hibernate3.support.HibernateDaoS y$+=>p|d.^
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upport; jO-T1P']Y
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import com.javaeye.common.util.PaginationSupport; DwGRv:&HH
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public abstract class AbstractManager extends nC(Lr,(
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HibernateDaoSupport { y+p"5s"
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privateboolean cacheQueries = false; w3;{z ,,T
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privateString queryCacheRegion; T+q5~~\d
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publicvoid setCacheQueries(boolean *zQhTYY
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cacheQueries){ VTU(C&"S
this.cacheQueries = cacheQueries; eA*We
} fA"c9(>m%]
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publicvoid setQueryCacheRegion(String Hy5 6@jW+E
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queryCacheRegion){ *R}p9;dpO
this.queryCacheRegion = 31\mF\{V
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queryCacheRegion; "~S2XcR[ E
} 0{
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publicvoid save(finalObject entity){ A'$>~Ev
getHibernateTemplate().save(entity); 4
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} Y9I|s{~
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publicvoid persist(finalObject entity){ Ii#+JY0k
getHibernateTemplate().save(entity); l$[,V:N
} 1]9l
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publicvoid update(finalObject entity){ y|=KrvMHJ
getHibernateTemplate().update(entity); R;pIi/yDRe
} n0G@BE1Y=
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publicvoid delete(finalObject entity){ U{qwhz(
getHibernateTemplate().delete(entity); v,Zoy|Lu
} [kTckZv
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publicObject load(finalClass entity, Khl0 ~
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finalSerializable id){ L)8%*X
return getHibernateTemplate().load 65nK1W`i
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(entity, id); F("|SOhc
}
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publicObject get(finalClass entity, xs
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finalSerializable id){ 2a;[2':
return getHibernateTemplate().get W7;RQ
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(entity, id); YI;MS:Qj
} 6Eus_aP
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publicList findAll(finalClass entity){ 7{l~\]6d
return getHibernateTemplate().find("from C4GkFD
r i)`e
" + entity.getName()); @iMF&\KC
} #
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publicList findByNamedQuery(finalString -knP5"TB
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namedQuery){ Gx4{ 9
return getHibernateTemplate 4'tY1d
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().findByNamedQuery(namedQuery); 'vYt_T
} !]5V{3
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publicList findByNamedQuery(finalString query, tv Zq):c
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finalObject parameter){ -r]L MQ
return getHibernateTemplate |lk:(~DM
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().findByNamedQuery(query, parameter);
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} X 4!Jj*
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publicList findByNamedQuery(finalString query, -%Ce
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finalObject[] parameters){ |f\WVGH
return getHibernateTemplate 4?+jvVq
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().findByNamedQuery(query, parameters); 4#.Q|vyl]"
} mg>wv[ 7
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publicList find(finalString query){ 2aX{r/Lc
return getHibernateTemplate().find sl(go^
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(query); ]rNxvFN*j
} lgD%
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publicList find(finalString query, finalObject
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parameter){ Oqt{ uTI~
return getHibernateTemplate().find d(@ ov^e-
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(query, parameter); f*IvaY
} HuKOb4g
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public PaginationSupport findPageByCriteria |/$954Hr#<
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(final DetachedCriteria detachedCriteria){ "zz b`T[8
return findPageByCriteria ~=t9-AF-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ie>mOsz
} 8J- ?bo
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public PaginationSupport findPageByCriteria }W(t>>
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(final DetachedCriteria detachedCriteria, finalint gjFQDrz(
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startIndex){
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return findPageByCriteria 1_]%,
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(detachedCriteria, PaginationSupport.PAGESIZE, vA[7i*D{w
,7DyTeMpN
startIndex); 94]i|2qj*
} ?Iij[CbU
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public PaginationSupport findPageByCriteria #yU"n-eLR
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(final DetachedCriteria detachedCriteria, finalint la4%Vqwgu
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pageSize, ~O!E &~
finalint startIndex){ -v|lM8
return(PaginationSupport) k,; (`L
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getHibernateTemplate().execute(new HibernateCallback(){ <OJqeUo+*\
publicObject doInHibernate _34%St!lg
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(Session session)throws HibernateException { <^'IC9D]
Criteria criteria = }_mMQg2>=
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detachedCriteria.getExecutableCriteria(session); y\[* mgl:
int totalCount = ,2i1 4H
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((Integer) criteria.setProjection(Projections.rowCount ?YDMl
=W2I0nr.
()).uniqueResult()).intValue(); O*x~a;?G
criteria.setProjection +
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(null); Dkh=(+> <
List items = x9 n(3Oa
- DYH>!
criteria.setFirstResult(startIndex).setMaxResults vQy<%[QO
}w2Et
(pageSize).list(); +_gA"I
PaginationSupport ps = gS`Z>+V5!c
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new PaginationSupport(items, totalCount, pageSize, cWo__EE
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startIndex); <Lt"e8Z> x
return ps; rSm#/)4A
} ae2SU4Jx
}, true); II[-6\d!
} Ge=\IAj
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public List findAllByCriteria(final b^()[4M;
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DetachedCriteria detachedCriteria){ =4U$9jo!;
return(List) getHibernateTemplate ,JTyOBB<I
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().execute(new HibernateCallback(){ {i3=N{5b
publicObject doInHibernate ] \!,yiVeU
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(Session session)throws HibernateException { ,9ew75Jl
Criteria criteria = E @Rb+8},"
* kUb[
detachedCriteria.getExecutableCriteria(session); 5lM 3In@
return criteria.list(); d-W*`:Q
} TIaiJvo
}, true); n!lE|if
} [9Tnp]q
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public int getCountByCriteria(final ]@}hyM[D;
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DetachedCriteria detachedCriteria){ !1]jk(Z
Integer count = (Integer) s$0dLEa9
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getHibernateTemplate().execute(new HibernateCallback(){ BJLeE}=H
publicObject doInHibernate F&3 :]1
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(Session session)throws HibernateException { ymnK `/J!Q
Criteria criteria = FP0GE
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detachedCriteria.getExecutableCriteria(session); +JXn
return A_2lG!!
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criteria.setProjection(Projections.rowCount CP$,fj
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()).uniqueResult(); 5Fq+^
} jMX|1b
}, true); P=y1qqC
return count.intValue(); 3Q )"
} \8vZZ t
} M9(lxu y1
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用户在web层构造查询条件detachedCriteria,和可选的 iV\*7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W3^^aD-
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PaginationSupport的实例ps。 )oM%
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ps.getItems()得到已分页好的结果集 c]qh)F$s8
ps.getIndexes()得到分页索引的数组 :3J`+V}9;
ps.getTotalCount()得到总结果数 r/0AM}[!*j
ps.getStartIndex()当前分页索引 qNMYZ0,
ps.getNextIndex()下一页索引 $?LegX
ps.getPreviousIndex()上一页索引 oJ#;X R
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~4] J'E >
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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 xf|C{XV@H
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一下代码重构了。 gh `_{l
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我把原本我的做法也提供出来供大家讨论吧: Y
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首先,为了实现分页查询,我封装了一个Page类: kn`O3cW/
java代码: #&z'?x^a
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/*Created on 2005-4-14*/ a\B?J
package org.flyware.util.page; (S6>^:;=~
]IDhE{
/** <u?\%iJ"
* @author Joa 6\y?+H1
* 'I>geW?{QK
*/ 1p<*11
publicclass Page { li#ep?5h^
gnf4H
V~
/** imply if the page has previous page */ U0N6\+
privateboolean hasPrePage; ;:Tb_4Hr
8\PI1U
/** imply if the page has next page */ _5OxESE
privateboolean hasNextPage; bJeF1LjS
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/** the number of every page */ SxkY ;^-U
privateint everyPage; 7$*x&We
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/** the total page number */ 9pk-#/ag
privateint totalPage; s>{\^T7y
zOy_qozk
/** the number of current page */ "K;""]#wg0
privateint currentPage; 5E}]U,$
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/** the begin index of the records by the current DD[<J:6
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query */ w.+G+r=
privateint beginIndex; ~{{7y]3M-
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/** The default constructor */ dMI G2log
public Page(){ c68,,rJO]i
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} X3~@U7DU
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/** construct the page by everyPage "DX2Mu=
* @param everyPage A3J=,aRI_v
* */ )vY )Mg
public Page(int everyPage){ /
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this.everyPage = everyPage; yEkwdx5!(
} ^pqJz^PO.
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/** The whole constructor */ Y+0GJuBf
public Page(boolean hasPrePage, boolean hasNextPage, =t.T9'{
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}yd!UU
int everyPage, int totalPage, 1`~.!yd8(
int currentPage, int beginIndex){ #f_.
this.hasPrePage = hasPrePage; 02YmV%
this.hasNextPage = hasNextPage; $Xs`'>,"
this.everyPage = everyPage; YmHu8H_Q
this.totalPage = totalPage; o,/w E
this.currentPage = currentPage; z0&Y_Up+5
this.beginIndex = beginIndex; !';;q
} ( yB]$
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/** ghTue*A
* @return O]oH}#5b
* Returns the beginIndex. N]F}Z#h
*/ ku#WQL
publicint getBeginIndex(){ M5N#xgR
return beginIndex; m@",Zr`f=
} HzsQ`M4cA
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/** RxVZn""
* @param beginIndex u7},+E)+B
* The beginIndex to set. E=]|v+#~
*/ ss`Sl$
publicvoid setBeginIndex(int beginIndex){ vb9C
this.beginIndex = beginIndex; k=O
} 7}pg7EF3z
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/** nW
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* @return O-3a U!L
* Returns the currentPage. @]Ac >&
*/ AP ]`'C
publicint getCurrentPage(){ P#[?Kfi
return currentPage; >.uIp4@(
} wVc^l
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/** 3`Xzp
* @param currentPage dq0!.gBT2
* The currentPage to set. /<"ok;Pu7
*/ K{ntl-D&y
publicvoid setCurrentPage(int currentPage){ /.>%IcK
this.currentPage = currentPage; Z,V<&9a;
} d)d0,fi?-
v[)8 1uY
/** TYCjVxfu$
* @return Q(x/&]7=V
* Returns the everyPage. 0g#x QzE
*/ Y+5aT(6O
publicint getEveryPage(){ bGxHzzU}
return everyPage; D&qJ@PR
} \m=k~Cf:f
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/** &q#.
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* @param everyPage ^z51f>C
* The everyPage to set.
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*/ IsDwa qd|
publicvoid setEveryPage(int everyPage){ wVX2.D'n<
this.everyPage = everyPage; r;+a%?P
} AHHV\r
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/** ,hm&]
* @return as@?
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* Returns the hasNextPage. %AmyT
*/ xqQK-?k
publicboolean getHasNextPage(){ T 2Yc` +
return hasNextPage; ph~BxK )i6
} ux6p2Sk;K
k *>"@
/** 7xfS%'=y"
* @param hasNextPage 3$.#\*s_4
* The hasNextPage to set. Mq_P'/
*/ ? 51i0~O=
publicvoid setHasNextPage(boolean hasNextPage){ " ]OROJGa
this.hasNextPage = hasNextPage; /Pg)@*~
} qd<I;*WV
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/** )JJF}m=
* @return "8~PfLJ+
* Returns the hasPrePage. ,H1K sN
*/ }F|B'[wn
publicboolean getHasPrePage(){ hE<Sm*HU
return hasPrePage; EV7lgKM^
} &xp]9$
l=x(
/** /!qP=ngw9
* @param hasPrePage 3[8p,wx
* The hasPrePage to set. OL_jU2,fv
*/ fK2r6D9
publicvoid setHasPrePage(boolean hasPrePage){ T6."j_
this.hasPrePage = hasPrePage; #T@k(Bz{L
} 2\;/mQI2A
z;_vl
/** nzbAQ3v
* @return Returns the totalPage. i1'G_bo4F7
* 5>ktr)]
*/ B{p74
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publicint getTotalPage(){ H!>>|6OPF
return totalPage; v["_t/_
} !~V^GlY
h4+*ssnYV
/** d24_,o\_
* @param totalPage ?'tRu !~
* The totalPage to set. kt=&mq/B
*/ 9A/bA|$
publicvoid setTotalPage(int totalPage){ 9%bErMHL
this.totalPage = totalPage; CxSh.$l
} /)`]p1c1%w
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} K}2G4*8S_G
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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 GLX{EG9Z
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个PageUtil,负责对Page对象进行构造: M|zTs\1I
java代码: !
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/*Created on 2005-4-14*/ *aFY+.;U`
package org.flyware.util.page; 29m$S7[
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import org.apache.commons.logging.Log; 3s67)n
import org.apache.commons.logging.LogFactory; <]X6%LX
9X
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/** FFN Sn
* @author Joa
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* M'F<1(
*/ c{KJNH%7
publicclass PageUtil { z(EpJK=`_
h=JW^\?\]
privatestaticfinal Log logger = LogFactory.getLog >5?:iaq
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(PageUtil.class); q]VB}nO
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/** "z;R"sv\
* Use the origin page to create a new page ~"<^4h
* @param page |lZp5MOc
* @param totalRecords ~sPXkLqK
* @return 1[$zdv{A
*/ TdT`Vf
publicstatic Page createPage(Page page, int =LKM)d=1
E|+<m!
totalRecords){ %g{)K)$,ui
return createPage(page.getEveryPage(), Pai8r%Zfu
yn_.
page.getCurrentPage(), totalRecords); j>uu3ADd2
} O:GAS [O`
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/** vxLr034
* the basic page utils not including exception [HUK
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_[-W*,xJ)
handler xR|^{y9n
* @param everyPage 9%"`9j~H>
* @param currentPage &I(\:|`o
* @param totalRecords qxsHhyB_n;
* @return page BW}M/
*/ }p?67y/
publicstatic Page createPage(int everyPage, int |lg jI!iK
}L&LtW{X
currentPage, int totalRecords){ +8x_f0<
everyPage = getEveryPage(everyPage); DvB{N`COd
currentPage = getCurrentPage(currentPage); '$EyVu!
int beginIndex = getBeginIndex(everyPage, XgM&0lVT
nMfR<%r
currentPage); }6<5mq)%
int totalPage = getTotalPage(everyPage, 4*Gv0#dga
41s\^'^&
totalRecords); v Y0ESc{
boolean hasNextPage = hasNextPage(currentPage, 8DY:a['-d
f}p`<z
totalPage); &/ED.K
boolean hasPrePage = hasPrePage(currentPage); RqP_^tB
RyG6_G}
returnnew Page(hasPrePage, hasNextPage, B]:|;d
everyPage, totalPage, ?6hd(^
currentPage, sR[!6[AA
)0ydSz`B
beginIndex); *Uj;a.
} k0#s{<I]E
h]+;"v6 /
privatestaticint getEveryPage(int everyPage){ LHXR7Fjc
return everyPage == 0 ? 10 : everyPage; zy nX9t
} `j9\]50Z>
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privatestaticint getCurrentPage(int currentPage){ rpDBKo
return currentPage == 0 ? 1 : currentPage; E2YVl%.
} Y6Cm
PxOQ
oP%5ymL%J
privatestaticint getBeginIndex(int everyPage, int hliO/3g
c$^v~lQS
currentPage){ 1X5Yp |Ho
return(currentPage - 1) * everyPage; NsSZ?ky
} l|E4 7@#
>]ZE<.
privatestaticint getTotalPage(int everyPage, int Us!ZQ#pP
G
&NK
totalRecords){ ZfH>UHft
int totalPage = 0; xkiiQs)
:vzIc3~c:`
if(totalRecords % everyPage == 0) }LKD9U5;8
totalPage = totalRecords / everyPage; *Egg*2P;"Q
else L8!yP.3
totalPage = totalRecords / everyPage + 1 ; 1"75+Q>D
WFFQxd|Z
return totalPage; O-K*->5S
} qsbV)c
PREGQ0
privatestaticboolean hasPrePage(int currentPage){ dE_"|,:
return currentPage == 1 ? false : true; *PV"&cx
} 7aKI=;60.
4%w<Ekd
privatestaticboolean hasNextPage(int currentPage, bv'>4a
la w$LL
int totalPage){ kp* !
return currentPage == totalPage || totalPage == JGTsVa2
CfP-oFHoQ
0 ? false : true; 3S]QIZ1
} =_z o
8.N`^Nj 1
_ahp7-O
} v[{7\Hha
-3v\ c~
O6)Po
.ml\z5
K sE$^`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 oe2*$\?.
u_
l?d
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 /.CS6W^z
")\V
做法如下: L6Brs"9B
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zGyRzxFN
C$~ly=@
的信息,和一个结果集List: 1Q!^*D
java代码: 2EZ7Vdz2
n7K%lj-.P
Q\
6-SAS
/*Created on 2005-6-13*/ ng9e)lU~*b
package com.adt.bo; ]=%qm;
*AW v
import java.util.List; fW+"Kuw
{d;z3AB
import org.flyware.util.page.Page; IF|;;*Z8
f<VK\%M
/** : slO0
* @author Joa 9?hZf$z
*/ jS[=Zx`
publicclass Result { :i?6#_2IC
h8 N|m0W
private Page page; 5R~M@
5$'[R;r
private List content; tzGQo5\
qve'Gm)
/** c1s&
* The default constructor 1.3dy]vG
*/ hk:>*B}
public Result(){ sL~4~178
super(); !E?+1WDS0
} E>tHKNyVTp
JfSe;
v
/** ox&?`DO
* The constructor using fields eS@j? Y0y
* M.}J SDt
* @param page kBcTXl
* @param content ]bh%pn
*/ cl`Wl/Q#
public Result(Page page, List content){ >.`*KQdan
this.page = page; vr4r,[B6y
this.content = content; h+j^VsP zB
} z{\tn.67
`14@dk
/** }BI6dZ~2A
* @return Returns the content. y,|2hrj/0E
*/ 76@W:L*J$J
publicList getContent(){ `G\Gk|4;2
return content; 0 {z8pNrc
} QJ(%rvn3
=LV-n
/** U!r8}@
* @return Returns the page. XK3O,XM
*/ ^O@eyP
public Page getPage(){ B!x#|vGXL
return page; l+P!I{n
} b)KEB9w
`MPR-"Z6
/** k &J;,)V
* @param content JfWkg`LqL
* The content to set. axvZA:l
*/ ph6'(,
public void setContent(List content){ G6a 2]
this.content = content; /96lvn]8lO
} dV
:}
{!wW,3|Pu
/** HYGd
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* @param page |rk.t g9
* The page to set. C/Z#NP~ *
*/ ;BH.,{*@B
publicvoid setPage(Page page){ .G\](%
this.page = page; wods
} /KOI%x
} cb]X27uww
q#mL-3OQ
bH/4f93Nb
77[TqRLf
;k `51=Wi
2. 编写业务逻辑接口,并实现它(UserManager, !;*flr`/
b_F1?:#
UserManagerImpl) )2Sh oFF
java代码: iTAj${ >
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Qgd
^SG>VfgC
/*Created on 2005-7-15*/ 0~RD@>]
package com.adt.service; "%D"h
\&kj#)JYA
import net.sf.hibernate.HibernateException; M KW~rrR
WFahb3kx
import org.flyware.util.page.Page; yXDjM2oR/2
*|W](id7e
import com.adt.bo.Result; wMR,r@}
\h#aPG<yo
/** W7uX
* @author Joa 5U7,,oyh
*/ :stHc,
publicinterface UserManager { .W~XX
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|=o -
public Result listUser(Page page)throws z*jaA;#
|}:}14ty
HibernateException; &nr{-][
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} _|12BVq
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jXf@JxQ
)e3w-es~4
DmuQE~DV
java代码: p
P@q
`
+`Q]p "G
"Tser*i )
/*Created on 2005-7-15*/ $%bd`d*S
package com.adt.service.impl; ,
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d)!'5ZrM
import java.util.List; +u$JMp
f?/OV *
import net.sf.hibernate.HibernateException; >qNpY(Ql
XV%R Mr6
import org.flyware.util.page.Page; 59 g//;35@
import org.flyware.util.page.PageUtil; H ;=^
W
#6|ve?`I
import com.adt.bo.Result; E3j`e>Yz
import com.adt.dao.UserDAO; ?sdSi--
import com.adt.exception.ObjectNotFoundException; 0`7yPq*
import com.adt.service.UserManager; AA^K/y
9;6)b0=$
/** 0M;El2
P$
* @author Joa QnS^ G{
*/ ._tEDY/1m
publicclass UserManagerImpl implements UserManager { ;303fS
cS YCMQ1ro
private UserDAO userDAO; kB CU+FC
-JEPh!oTt
/** s(fkb7W,gO
* @param userDAO The userDAO to set. T.I'c6|
*/ O@@nGSc@
publicvoid setUserDAO(UserDAO userDAO){ #$S~QS.g
this.userDAO = userDAO; {~O4*2zg;K
} !5De?OXe
\8C<nh
/* (non-Javadoc) #n+u>x.O
* @see com.adt.service.UserManager#listUser iYT?6Y|+
)tJaw#Mih
(org.flyware.util.page.Page) !Ltx2CB2]
*/ )=}qAVO8
public Result listUser(Page page)throws &aIFtlC
}G{"Mp4
HibernateException, ObjectNotFoundException { bi}aVtG~z
int totalRecords = userDAO.getUserCount(); dF51_Kk
if(totalRecords == 0) ~;$QSO\2h
throw new ObjectNotFoundException L3oL>r'|
LqD7SJ}/f
("userNotExist"); ?Ybq]J\q
page = PageUtil.createPage(page, totalRecords); ~fD\=- S1
List users = userDAO.getUserByPage(page); DTA$,1JuD
returnnew Result(page, users); x f{`uHa8
} 9O&gR46.
R[\1Kk(Zo
} y lczM^@
Q]=/e7
\='LR!_
JL#LCU
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6 M:?W"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1SS1P0Ur
H%l-@::+$
询,接下来编写UserDAO的代码: d:>^]5cE&
3. UserDAO 和 UserDAOImpl: U5j4iz'
java代码: FYFlh^}
>%`SXB&9
N}nE9z5
/*Created on 2005-7-15*/ O&/nBHu\
package com.adt.dao; >ryA:TO{
(|AZO!
import java.util.List; Jf=V<
u8JH~b
import org.flyware.util.page.Page; _y6iR&&x
UmpHae
import net.sf.hibernate.HibernateException; \41/84BA
.9ZK@xM&?
/** 'vtJl
* @author Joa ygja{W.
*/ RTd,bi*
publicinterface UserDAO extends BaseDAO { -`Z!p
1mtYap4
publicList getUserByName(String name)throws 0sw;h.VY
B2$cY;LH
HibernateException; h`9 & :zr
:+\sKEzL
publicint getUserCount()throws HibernateException; jcJ@A0]
V /\Y(Mxc
publicList getUserByPage(Page page)throws g?xXX
/Qe
I:DAn!N-A*
HibernateException; DFZ0~+rh
9xJtDdy-O
} uHacu<$=
J?#vL\8
7wW x 8
5V(#nz
dKEy6C"@
java代码: w2b(,w
(5Q<xJ
RgH 6l2
/*Created on 2005-7-15*/ v9@_DlV\
package com.adt.dao.impl; 2Jiy`(P
`Mg3P_}=
import java.util.List; l v:GiA"X
0@{bpc rc
import org.flyware.util.page.Page; k1g-%DB
l%Ke>9C
import net.sf.hibernate.HibernateException; R*cef
import net.sf.hibernate.Query; W.{+0xx
H~#$AD+H
import com.adt.dao.UserDAO; U9PI#TX
&O
uAnL`
/** sF :pwI5^
* @author Joa g2?W@/pa
*/ &?p(UY7'"
public class UserDAOImpl extends BaseDAOHibernateImpl b-VQn5W
Q~f]?a`
implements UserDAO { @b 17jmq{
D,p2MBr
/* (non-Javadoc) 1jKj'7/K
* @see com.adt.dao.UserDAO#getUserByName {G3Ok++hc
5ad@}7&
(java.lang.String) _-{=Z=?6}
*/ 1+3-Z>^ e
publicList getUserByName(String name)throws 3TjyKB *!
C[TjcHoA
HibernateException { c^H#[<6p
String querySentence = "FROM user in class f:P;_/cJc
lz>.mXdx
com.adt.po.User WHERE user.name=:name"; .1^Kk3
Query query = getSession().createQuery R(_WTs9x4
+Q5'!@8
(querySentence); ^FNju/b
query.setParameter("name", name); yRQ1Szbjli
return query.list(); qh}+b^Wi
} =v?V
YwH Fn+
/* (non-Javadoc) $!p2Kf>/Q
* @see com.adt.dao.UserDAO#getUserCount() @Kt!uKrI
*/ tr0kTW$Ad
publicint getUserCount()throws HibernateException { =C(BZ+-^
int count = 0; ]YZ_kc^(V;
String querySentence = "SELECT count(*) FROM F&7Z(
vnbY^ASdw
user in class com.adt.po.User"; t6e6v=.Pg
Query query = getSession().createQuery Y/m-EL
)iIsnM
(querySentence); t vW0 W
count = ((Integer)query.iterate().next G]xN#O;
,f?B((l
()).intValue(); 7,?ai6{
return count; kAUL7_>6X
} JB5%\
Ssir?ZUm
/* (non-Javadoc) peS4<MqWu
* @see com.adt.dao.UserDAO#getUserByPage T$FKn
Ai 8+U)
(org.flyware.util.page.Page) P^q!Pye
*/ 2Nm{.Y
publicList getUserByPage(Page page)throws P9`CW
c?c"|.-<p
HibernateException { x) %"i)
String querySentence = "FROM user in class *<{hLf
&Nr+-$
com.adt.po.User"; 1p/_U?H:|
Query query = getSession().createQuery d"3x11|
$*XTX?,'
(querySentence); S:g6z'e1
query.setFirstResult(page.getBeginIndex()) 71<4q{n
.setMaxResults(page.getEveryPage()); tmoclK-
return query.list(); SFP?ND+7
} J1M9),
9}K
K]m6u}
} h3\(660>$
p@DVy2,EY
y^X]q[-?
8c%N+E]
j{tr''yN
至此,一个完整的分页程序完成。前台的只需要调用 w9x5 IRW k
E6Uj8]P`
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?u{Mz9:?HT
!qH)ttW
的综合体,而传入的参数page对象则可以由前台传入,如果用 ^{8CShUCv
X`E}2|q'
webwork,甚至可以直接在配置文件中指定。 {~\:4
r|bGn#^
下面给出一个webwork调用示例: #{)mr [c|
java代码: Y!(w. G
7oL:C
(o\D=!a
/*Created on 2005-6-17*/ 1]8Hpd
package com.adt.action.user; 3s*mq@~1X
`'(@"-L:7
import java.util.List;
6|6O|
<o
$`C$|9S
import org.apache.commons.logging.Log; Hp(41Eb,
import org.apache.commons.logging.LogFactory; :q2RgZE
import org.flyware.util.page.Page; 5Ktll~+:#
-
ikq#L){
import com.adt.bo.Result; :de4Fje/4y
import com.adt.service.UserService; n34d"l3
import com.opensymphony.xwork.Action; h^{aG ])
r24
s_
/** kMa|V0
* @author Joa Dn>C
:YS`
*/ .lz=MUR
publicclass ListUser implementsAction{ +).=}.k
>k}Kf1I
privatestaticfinal Log logger = LogFactory.getLog }g 2l
ni
G"
(ck4
(ListUser.class); *li5/=UC5*
+&1#ob"6lq
private UserService userService; -)ri,v{:c
']X0g{%
private Page page; m[N&UM#
s2+_`Ogg
privateList users; yaI jXv
85FzIX-F%
/* ^(qR({cX
* (non-Javadoc) BSEP*#s
* 8rz,MsFR
* @see com.opensymphony.xwork.Action#execute() f[OJqk
*/ FT gt$I
publicString execute()throwsException{ )Z:maz
Result result = userService.listUser(page); OtT*)8*c
page = result.getPage(); aMgg[g9>t
users = result.getContent(); EY :EpVin
return SUCCESS; M?ElD1#Z
} xaIe7.Z"xo
ciPq@kMV
/** FlH=Pqc
* @return Returns the page. T(kG"dz
*/ p|)j{nc
public Page getPage(){ gF~
}
return page; 0}Qd
} fAT
M?
|'L$ogt6
/** {~=gKZ:-@
* @return Returns the users. Xu{S4#1
*/ R"71)ob4
publicList getUsers(){ vrsOA@ee3H
return users; pD6a+B\;k
} '&y+,2?;Y[
rAu@`H?
/** \#'m([<e
* @param page hl+
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* The page to set. f[$Z<:D-ve
*/ W TC/mcS
publicvoid setPage(Page page){ oJ0
#U
this.page = page; w 1O)
} yjChnp
Cc
zhACNz4tJ
/** 7(zY:9|(
* @param users SciEHI#
* The users to set. "3a_C,\
*/ VZU@G)rd
publicvoid setUsers(List users){ wOl]N2<
this.users = users; _8?r!D#P;s
} f{R/rb&iB
1uc;:N G=
/** @|7e~U
* @param userService S#Pni}JD
* The userService to set. Q"`J-#L
*/ ^Pc&`1Ap
publicvoid setUserService(UserService userService){ G^w:c]
this.userService = userService; MSS0Sx<f
} !r_2b! dy
} t. kOR<
-;[,`g(f
-<n]Sv;V
h&t9CpTfeJ
+dK;\wT
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, VQ`a-DL
nnnq6Z}
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 'uF"O"*
Q-f?7*>
么只需要: Gn?<~8a
java代码: z_ia3k<
>z69r0)>
cpBTi
<?xml version="1.0"?> !W45X}/o
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork l0{R`G,
k/lDE
1.0//EN" "http://www.opensymphony.com/xwork/xwork- UxVxnJ_
+S}/6dg
1.0.dtd"> ^y&sKO
1bJrEXHXy
<xwork> #ZpR.$`k
7-MkfWH2b6
<package name="user" extends="webwork- AU^5N3%j
!qVnziE,,
interceptors"> 8 gzf$Oc
p EbyQ[
<!-- The default interceptor stack name S9S%7pE
c{K[bppJ*
--> y[sO0u\
<default-interceptor-ref 8Ir
= @
[cf!%3>53
name="myDefaultWebStack"/> I>z0)pB
XVkCYh4,
<action name="listUser" Kh2!c+Mw
);5H<[
class="com.adt.action.user.ListUser"> kG$U
<param vTUhIFa{
H~r":A'"*
name="page.everyPage">10</param> Lkl^
`
<result Mi&jl_&
TbA=bkj[4
name="success">/user/user_list.jsp</result> \ POQeZ
</action> X=i",5;
]Br6!U4~
</package> YhNO{4D
/%w3(e
</xwork> GbN|!,X1m
)wueR5P
E(G&mfhb
$fl+l5?9
a EmLf
,fW%Qv
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 $^j#z^7
/L? ia
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 2io~pk>
MF/@Efjn
]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
tEHgQto
ae|j#!~oi
K/ 5U;oC
1=Nh<FuQ
ct![eWsuB
我写的一个用于分页的类,用了泛型了,hoho ~zT7 43
R\d)kcy4
java代码: sW]fPa(cn,
aJ^RY5
]KE"|}B
package com.intokr.util; B(h%>mT[
TdWatvY5p
import java.util.List; .7|Iausv
%uy5la
/** 24Uvi:B?~
* 用于分页的类<br> 5|0}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> UCVdR<<Z
* ==)q{e5
* @version 0.01 Yb;$z'
* @author cheng XdxSi"+
*/ >qC,IQ'
public class Paginator<E> { _[t:Vme}v
privateint count = 0; // 总记录数 7@uhw">mX
privateint p = 1; // 页编号 @X g5E
privateint num = 20; // 每页的记录数 o{?R z3z
privateList<E> results = null; // 结果 4RoE>m1[G
g,]GzHV1
/** Ek%mX"
* 结果总数 XlDN)b5v{
*/ `4kVe= {
publicint getCount(){ GP{$w_'!J0
return count; @m+2e C77
} %29lDd(<
B
EB[K2[9
publicvoid setCount(int count){ !)$e+o^W
this.count = count; @\s*f7
} S5>?jn1
ft><Ql3
/** f )Ef-o
* 本结果所在的页码,从1开始 KO3X)D<3
* NY3.?@Z
* @return Returns the pageNo. d !=AS
*/ b:t|9FE%
publicint getP(){ j;SK{Oq
return p; ,A9_xdv5
} '
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x,: DL)$1
/** 5~GH*!h%;
* if(p<=0) p=1 ,zVS}!jRhy
* ]m<z
* @param p >&%#`PKT
*/ VtnVl`/]
publicvoid setP(int p){ PJ3M,2H1b.
if(p <= 0) '4"c#kCKL
p = 1; S-%itrB*
this.p = p; [2\jQv\Y
} }^tW's8
B3g#)
/** <e'/z3TbRW
* 每页记录数量 3}kG ]#
*/ q@[UeXu?pZ
publicint getNum(){ c.4WwzK
return num; IF'Tj`yD
} o'J^kd`
*!m(oP
/** u1;sH{YK>
* if(num<1) num=1 mr2fNA>kR
*/ dwJnPJ=z
publicvoid setNum(int num){ </]a`h]
if(num < 1) #sM`>KG6T1
num = 1; / ?Hq
this.num = num; {L/hhKT
} F_ -}GN%
Xb2.t^
]f
/** 7.FD16
* 获得总页数 _?v&\j
*/ !q!5D`
publicint getPageNum(){ h,|. qfUk
return(count - 1) / num + 1; >["X(%&w
} *b8AN3!
K( r@JW
/** *3\ Nj6
* 获得本页的开始编号,为 (p-1)*num+1 "6q@}sz!
*/ \c4D|7\=
publicint getStart(){ 7Fzj&!>ti
return(p - 1) * num + 1; sT'j36Nc<,
} 08G${@D+X0
U(/8dCyyY
/** V@o#" gZ
* @return Returns the results. {5Sy=Y
*/ fUq:`#Q
publicList<E> getResults(){ J_ 7#UjGA,
return results; /tj_WO_
} bXi(]5
suHisc*
public void setResults(List<E> results){ L@"&s#~=3
this.results = results; rT_J6F5J
} rT(b t~Z
yb6gYN
public String toString(){ XwIKpr8
StringBuilder buff = new StringBuilder <f#pS[A
z1nKj\AM2
(); "7J38Ej\
buff.append("{"); ZRj/lQ2D
buff.append("count:").append(count); ^cCNQS}r
buff.append(",p:").append(p); S$ n?
buff.append(",nump:").append(num); 0+T:};]
buff.append(",results:").append mJZB@m u?
-QK- w>
(results); xX.kKEo"d
buff.append("}"); '*D>/hn|:]
return buff.toString(); |j=Pj)5J
} S!66t?vHB
EV@yJ]
} I,W`s
wOg#J
'| p"HbJ