Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 VZo[\sWf
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ST$~l7p
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 !.1oW(
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 c} )U:?6
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分页支持类: c'cK+32
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java代码: TI4#A E
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package com.javaeye.common.util; hhd%j6
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import java.util.List; `)V1GR2
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publicclass PaginationSupport { y4*i
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publicfinalstaticint PAGESIZE = 30; .4on7<-a
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privateint pageSize = PAGESIZE; Pyh+HD\
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privateList items; .nN=M>#/
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privateint totalCount; vD<6BQR
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privateint[] indexes = newint[0]; *69{#qN
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privateint startIndex = 0; _CqVH5U?
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public PaginationSupport(List items, int I5]=\k($
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totalCount){ |vW(;j6
setPageSize(PAGESIZE); .{+KKa $@G
setTotalCount(totalCount); xz2U?)m;x
setItems(items); qLrvKoEX2
setStartIndex(0); J{>9ctN
} )9/.K'o,dy
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public PaginationSupport(List items, int j"(o>bv7
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totalCount, int startIndex){ 9/A$3#wF
setPageSize(PAGESIZE); 5=/&[=
setTotalCount(totalCount); /`(Kbwh
setItems(items); 0XouHU
setStartIndex(startIndex); UNLmnj;-Q
} X3[gi`
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public PaginationSupport(List items, int =KQQS6
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totalCount, int pageSize, int startIndex){ vByt_X
setPageSize(pageSize); =&+]>g{T
setTotalCount(totalCount); 337y,;
setItems(items); eC%uu
setStartIndex(startIndex); =5:L#` .
} B
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publicList getItems(){ |-Rg].
return items; =$ bJ`GpJ
} aq~>$CHa
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publicvoid setItems(List items){ t][U`1>i
this.items = items; zED#+-7
} )ph**g
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publicint getPageSize(){ U@t"o3E
return pageSize; $DPMi9,7^
} ?O(@BT
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publicvoid setPageSize(int pageSize){ ]5(T{
this.pageSize = pageSize; _#[~?g`
} SCwAAE9s]
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publicint getTotalCount(){ pypW
return totalCount; 5>9KW7^L
} i4<&zj})
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publicvoid setTotalCount(int totalCount){ :Y? L*
if(totalCount > 0){ ;8F|Q<`pV
this.totalCount = totalCount; /zt9;^e
int count = totalCount / \9;SOA v
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pageSize; j^4KczJl
if(totalCount % pageSize > 0) zk6al$3R
count++; RYhaQ&1i
indexes = newint[count]; W&M=%
for(int i = 0; i < count; i++){
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indexes = pageSize * eZ>KA+C[
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i; ^b{ -y
} 7RXTQ9BS
}else{ ~\vGwy
this.totalCount = 0; \VY!= 9EV
} n oWjZ
} }E
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publicint[] getIndexes(){ u_kcuN\Sq
return indexes; ceiUpWMu,
} kXjrc
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publicvoid setIndexes(int[] indexes){ 01N]|F:
this.indexes = indexes; '*4>&V.yX
} z@70{*
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publicint getStartIndex(){ .`I;qF
return startIndex; \o|5/N
} 1yFVF
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publicvoid setStartIndex(int startIndex){ yQP!Vt^
if(totalCount <= 0) aJ!(c}N~97
this.startIndex = 0; +jpaBr-O#
elseif(startIndex >= totalCount) $x5,Oe n
this.startIndex = indexes b*;zdGX.A9
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[indexes.length - 1]; N+)gYb6h
elseif(startIndex < 0) ]YQ!i@Y
this.startIndex = 0; {J aulg
else{ /5x~3~
this.startIndex = indexes } kNbqwVP
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[startIndex / pageSize]; )^Ha?;TS
} iTX:*$~I
} 1\'?.
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publicint getNextIndex(){ C]X:@^Hy
int nextIndex = getStartIndex() + "7w~0?}
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pageSize; ;q=0NtCS=4
if(nextIndex >= totalCount) ^[UWG^d
return getStartIndex(); $q"/q*ys
else B #[URZ9S
return nextIndex; ~ RdD6V
} '7'*+sgi$
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publicint getPreviousIndex(){ fG *1A\t]
int previousIndex = getStartIndex() - P4\{be>e
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pageSize; E?VPCx
if(previousIndex < 0) 0r4,27w
return0; &1=Je$,
else rLkUIG
return previousIndex; 9EPE.+ns
} v jTs[eq>
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} 2yB@)?V/
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抽象业务类 o{W4@:Ib
java代码: R*"31&3le4
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/** uTWij4)a
* Created on 2005-7-12 y v$@i A
*/ |8QXjzH
package com.javaeye.common.business; 2H,^i,
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import java.io.Serializable; .Mn_T*F
import java.util.List; z~O#0Q!
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import org.hibernate.Criteria; tK
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import org.hibernate.HibernateException; N5ph70#y3
import org.hibernate.Session; 3SI~?&HU!/
import org.hibernate.criterion.DetachedCriteria; +hUS
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import org.hibernate.criterion.Projections; xSf&*wLE
import KA[8NPhzZ
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org.springframework.orm.hibernate3.HibernateCallback; P#0U[`ltK
import Moldv
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org.springframework.orm.hibernate3.support.HibernateDaoS WfdM~k\
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upport; i 4}4U
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import com.javaeye.common.util.PaginationSupport; x4_xl
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public abstract class AbstractManager extends zeC@!,lH
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HibernateDaoSupport { mQbpv'N
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privateboolean cacheQueries = false; uVSc1MS1
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privateString queryCacheRegion; tRUGgf`
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publicvoid setCacheQueries(boolean he
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cacheQueries){ a>05Yxw
this.cacheQueries = cacheQueries; :
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} =7e|e6
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publicvoid setQueryCacheRegion(String ?cZ#0U
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queryCacheRegion){ l[,RA?i
{
this.queryCacheRegion = nDFF,ge;a#
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queryCacheRegion; o4[
} +zl2|'
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publicvoid save(finalObject entity){ ^(Y}j8sj
getHibernateTemplate().save(entity); <FkoWN
} Dc1tND$X3g
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publicvoid persist(finalObject entity){ <P%<EgOE
getHibernateTemplate().save(entity); FX->_}kL=
} 2!w5eWl,
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publicvoid update(finalObject entity){ #1-2)ZO.
getHibernateTemplate().update(entity); _EusY3q
} |}FK;@'I 6
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publicvoid delete(finalObject entity){ .uoQ@3
getHibernateTemplate().delete(entity); 7A@iu*t
} b|rMmx8vA
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publicObject load(finalClass entity, ZH1W#dt`[
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finalSerializable id){ \ZOH3`vq
return getHibernateTemplate().load +,g"8&>
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(entity, id); ,A{'lu
} *GGiSt
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publicObject get(finalClass entity, ?*nFz0cs^
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finalSerializable id){ cn3F3@_"\
return getHibernateTemplate().get HCCEIgCT
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(entity, id); en5sqKqh+
} q!qOy/}D
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publicList findAll(finalClass entity){ l>kREfHq!{
return getHibernateTemplate().find("from v/s6!3pnl
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" + entity.getName()); fYt
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} D)_67w|u|
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publicList findByNamedQuery(finalString 9>OPaLn
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namedQuery){ 4g%BCGsys
return getHibernateTemplate kp$w)%2JW
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().findByNamedQuery(namedQuery); k^%Kw(/
} fqY;>Z
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publicList findByNamedQuery(finalString query, fPA5]a9
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finalObject parameter){ Ch;wvoy
return getHibernateTemplate c*@#0B
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().findByNamedQuery(query, parameter); ^W*T~V*8
} O/N@Gz[g%
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publicList findByNamedQuery(finalString query, >Av[`1a2F
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finalObject[] parameters){ 45qSt2
return getHibernateTemplate K.R4.{mo
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().findByNamedQuery(query, parameters); Dus [N<
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} A@?Rj
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publicList find(finalString query){ jfOqE*frl!
return getHibernateTemplate().find 5.TeH@(
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(query); xIlo@W6
} 1[4)Sq?
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publicList find(finalString query, finalObject d'okXCG
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parameter){ LT2UY*
return getHibernateTemplate().find |n/qJIE6
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(query, parameter); )[]*Y]vSx
} gd,3}@@SH
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public PaginationSupport findPageByCriteria 5dNM:1VoE
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(final DetachedCriteria detachedCriteria){ Y48MCL
return findPageByCriteria #86=[*Dr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \$B%TY
} yd>b2 M
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public PaginationSupport findPageByCriteria $.0l% $ 7
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(final DetachedCriteria detachedCriteria, finalint xk/osbKn
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startIndex){ N,?4,+Hc-
return findPageByCriteria $[*QsU%%
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(detachedCriteria, PaginationSupport.PAGESIZE, >69- [#P!
6 *GR_sMm
startIndex); /9 ^F_2'_
} K
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public PaginationSupport findPageByCriteria oj'a%mx
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(final DetachedCriteria detachedCriteria, finalint 2Vwv#NAV k
*)|EWT?,
pageSize, IBn+42V
finalint startIndex){ oWP3Y.
return(PaginationSupport) ~B704i
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getHibernateTemplate().execute(new HibernateCallback(){ ;NJx9)7<
publicObject doInHibernate cmu| d
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(Session session)throws HibernateException { m.g2>r`NU
Criteria criteria = [(kC/W)!
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detachedCriteria.getExecutableCriteria(session); =K:)%Qh
int totalCount = ~_GW
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((Integer) criteria.setProjection(Projections.rowCount J4l\
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()).uniqueResult()).intValue(); 02RZ>m+
criteria.setProjection CUI\:a-
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(null); +f"q^R IU
List items = 6M^NZ0~J
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criteria.setFirstResult(startIndex).setMaxResults ^Q9;ro*;ck
]K!NLvz
(pageSize).list(); +!JTEKHKH
PaginationSupport ps = (l_/ HQ32
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new PaginationSupport(items, totalCount, pageSize, dZ6P)R
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startIndex); vLT$oiN[c
return ps; +v{g'
} |J^}BXW'^)
}, true); wOLA8UYW
} ^NB\[ &
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public List findAllByCriteria(final - xE%`X
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DetachedCriteria detachedCriteria){ ??
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return(List) getHibernateTemplate E-v#G~
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().execute(new HibernateCallback(){ N/V~>UJ0{*
publicObject doInHibernate HD~o]l=H
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(Session session)throws HibernateException { tE(_Cg
Criteria criteria = `iZ){JfAH
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detachedCriteria.getExecutableCriteria(session); 30fqD1_{
return criteria.list(); Bid+,,
} F[5sFkM7
}, true); :v
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} #KgDOCQH
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public int getCountByCriteria(final 0Bn35.K
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DetachedCriteria detachedCriteria){ w'Vm'zo
Integer count = (Integer) .EB'n{zxd
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getHibernateTemplate().execute(new HibernateCallback(){ <nk7vo?Ks
publicObject doInHibernate e anR$I;Yj
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(Session session)throws HibernateException { #]5A|-O^
Criteria criteria = YW7Pimks
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detachedCriteria.getExecutableCriteria(session); 8:gUo8
return =pnMV"'9
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criteria.setProjection(Projections.rowCount B }t529Z
-
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()).uniqueResult(); e jh0Wfl
} X"EZpJ'W
}, true); g/(3D
return count.intValue(); ~m6b6Aj@6
} ttd
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} aESlbH
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用户在web层构造查询条件detachedCriteria,和可选的 R|'ftFebB.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ,p)Qu%'
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PaginationSupport的实例ps。 +aZcA#%
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ps.getItems()得到已分页好的结果集 ,JqCxb9
ps.getIndexes()得到分页索引的数组 B6-1q&
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ps.getTotalCount()得到总结果数 SSn{,H8/j
ps.getStartIndex()当前分页索引 Msst:}QY
ps.getNextIndex()下一页索引 ]S+KH
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ps.getPreviousIndex()上一页索引 Y_=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 bZlKy`Z
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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 Y|nC_7&Bv
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一下代码重构了。 `
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我把原本我的做法也提供出来供大家讨论吧: S~hoAl"xb/
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首先,为了实现分页查询,我封装了一个Page类: MG:eI?G/'
java代码: ,lDOo+eE%:
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/*Created on 2005-4-14*/ !6FO[^h||H
package org.flyware.util.page; [79iC$8B|
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/** k*K.ZS688
* @author Joa uJSzz:\
* e]*@|e4b
*/ UW'@3#<?
publicclass Page { cnz+%Y N
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/** imply if the page has previous page */ v(P5)R,
privateboolean hasPrePage; g+]o=@
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/** imply if the page has next page */ ,FL*Z9wA
privateboolean hasNextPage; 3YD.Fjz$
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/** the number of every page */ #<DS-^W!
privateint everyPage; x4XCR,-
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/** the total page number */ yYiu69v
privateint totalPage; V*gh"gZ<
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/** the number of current page */ 5S
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privateint currentPage; VQ8Q=!]
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/** the begin index of the records by the current 2= zw!
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query */ gX]ewbPDQ
privateint beginIndex; |ITh2m
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/** The default constructor */ Z '~Ie~
public Page(){ H>F j
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} #z =$*\u
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/** construct the page by everyPage r2m&z%N&
* @param everyPage \k3EFSm
* */ 6t4Khiwx
public Page(int everyPage){ \Vx_$E
this.everyPage = everyPage; 1ZY~qP+n+
}
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/** The whole constructor */ ;r}yeISf
public Page(boolean hasPrePage, boolean hasNextPage, <72q^w
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int everyPage, int totalPage, }H:wgy`
int currentPage, int beginIndex){ LZDJ\"a-
this.hasPrePage = hasPrePage; >%LY0(hY3
this.hasNextPage = hasNextPage; rgF4 W8
this.everyPage = everyPage; )]C(NTfxg
this.totalPage = totalPage; oQ}K_}{>
this.currentPage = currentPage; 9qvl9,*g
this.beginIndex = beginIndex; 8cGoo u6
} Ey)ey-'\
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/** (0["|h32,
* @return 7Y5.GW\^
* Returns the beginIndex. N(%(B
*/ ZF@$3
publicint getBeginIndex(){ Of>2 m<
return beginIndex; \. a 7F4h
} O9rA3qv
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/** 5zz">-Q !
* @param beginIndex >qZl
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* The beginIndex to set. gxmY^"Jy
*/ Xi;<O&+
publicvoid setBeginIndex(int beginIndex){ Aw&0R" {
this.beginIndex = beginIndex; hQeG#KQ
} Ax*xa6_2
mrBK{@n
/** )Em`kle
* @return o4jh n[Fx
* Returns the currentPage. s8dP=_ `
*/ Z1_F)5pn
publicint getCurrentPage(){ :eIQF7-
return currentPage; beB3*o
} [\rzXE
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/** Y
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* @param currentPage C;~LY&=
* The currentPage to set. tIS.,CEQF
*/ *T~b
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publicvoid setCurrentPage(int currentPage){ 1024L;
this.currentPage = currentPage; n=?wX#rEC#
} *fz#B/_o
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/** a(LtiO
* @return ,(&Fb~r]
* Returns the everyPage. M 5$JB nN
*/ I&`aGnr^^
publicint getEveryPage(){ GT\yjrCd
return everyPage; Ns]$+|
} jig3M N
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/** I%NeCd
* @param everyPage m\70&%v
* The everyPage to set. a#lytp
*/ rBOH9L
publicvoid setEveryPage(int everyPage){ X#HH7V>
this.everyPage = everyPage; nuVux5:
} %y7ZcH'
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/** qWf[X'
* @return USaa#s4'
* Returns the hasNextPage. 2A:&Cqo
*/ WNt':w^_
publicboolean getHasNextPage(){ w[ $oH^7
return hasNextPage; m6#a{
} 'Va<GHr>+
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/** J*38GX+
* @param hasNextPage \(--$9
* The hasNextPage to set. /pV N1Yt
*/ 8nWPt!U:
publicvoid setHasNextPage(boolean hasNextPage){ H>},{ z
this.hasNextPage = hasNextPage; hy>0'$mU
} )5n:UD{f[#
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/** B&_Z&H=
* @return I0qJr2[X~
* Returns the hasPrePage. I1rB,%p
*/ jo3(\Bq
publicboolean getHasPrePage(){ u-tD_UIck
return hasPrePage; ^qi+Y)dU|
} 9hssIZO
sPVE_n
/** ,SNt*t1"
* @param hasPrePage 3hxV`rb
* The hasPrePage to set. 6}VFob#h8
*/ S^D7}
publicvoid setHasPrePage(boolean hasPrePage){ ><S(n#EB
this.hasPrePage = hasPrePage; o
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} |5ge4,}0
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/** W;l0GxOxQ
* @return Returns the totalPage. qHtIjtt[q
* Z}t^i^u
*/ 0Lb{HLT
publicint getTotalPage(){ luyu7`
return totalPage; y0ObcP.MA
} @WJ\W `P
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/** &,=FPlTC=
* @param totalPage e6bh,BwgQq
* The totalPage to set. BoST?"&}'
*/ W-gu*iZ6&
publicvoid setTotalPage(int totalPage){ Z`86YYGK
this.totalPage = totalPage; t\a|Gp W
} p&5>j\uJ1&
y/kB`Z(Yj
} 0igB pHS
@rAV;D%
W/b)OlG"2
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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 +S[3HX7H
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个PageUtil,负责对Page对象进行构造: 0w0{@\9
java代码: $zU%?[J
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/*Created on 2005-4-14*/ vU5}E\Ny
package org.flyware.util.page; (CgvI*O
bar=^V)
import org.apache.commons.logging.Log; 8ZqLGa]
import org.apache.commons.logging.LogFactory; 3Zl:rYD?
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/** Lq1?Y
* @author Joa MB $aN':
* &:IcwD&
*/ E/*&'Osq
publicclass PageUtil { cIG7Q"4
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privatestaticfinal Log logger = LogFactory.getLog z6rT<~xZtu
i;s;:{cn
(PageUtil.class); Pr(@&:v:
{
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/**
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* Use the origin page to create a new page HZ2W`wo
* @param page {:#nrD"
* @param totalRecords >iRkhA=Vg
* @return &"I csxG
*/ s@5~HyeI
publicstatic Page createPage(Page page, int iP;"-Mj
)p1~Jx( \
totalRecords){ y Vm>Pj6
return createPage(page.getEveryPage(), X{Hh^H
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page.getCurrentPage(), totalRecords); ;gSRpTS:
} y1T(R#
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/** ;^0rY )&
* the basic page utils not including exception J 7 G-qF\
tq3Rc}
handler %>_6&A{K,d
* @param everyPage %=Z/Frd
* @param currentPage j*Pq<[~
* @param totalRecords MpGG}J[y
* @return page j7Ts&;`[*
*/ rUmP_
publicstatic Page createPage(int everyPage, int FMI1[|:;
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currentPage, int totalRecords){ :$,MAQ'9
everyPage = getEveryPage(everyPage); o|xZ?#^h
currentPage = getCurrentPage(currentPage); dFDf/tH
int beginIndex = getBeginIndex(everyPage, i}P{{kMJ
;RX u}pd
currentPage); v=0G&x=/
int totalPage = getTotalPage(everyPage, ..+#~3es#y
' h<(
totalRecords); fByf~iv,
boolean hasNextPage = hasNextPage(currentPage, EY<"B2_%
m8b,_1
totalPage); !khEep}
boolean hasPrePage = hasPrePage(currentPage); 1' v!~*af
qy)~OBY
returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, ujSoWs
currentPage, 5Gy#$'kdf
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beginIndex); geqP. MR
} *|Er;Thw
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privatestaticint getEveryPage(int everyPage){ C !Srv7
return everyPage == 0 ? 10 : everyPage; \3^ue0
} 1ONkmVtL
gCC7L(1
privatestaticint getCurrentPage(int currentPage){ t(-,mw
return currentPage == 0 ? 1 : currentPage; zU+q03l8Ur
} p/VVb%
u;-fG9xs
privatestaticint getBeginIndex(int everyPage, int xlu4
ByJPSucD
currentPage){ 0V(}Zj>
return(currentPage - 1) * everyPage; Zx_^P:rL
} "O<ETHd0
2~?E'
privatestaticint getTotalPage(int everyPage, int ~"#HHaBO#
L*[3rqER
totalRecords){ ^PezV5(
int totalPage = 0; wN4#j}C
]lBCK
if(totalRecords % everyPage == 0) dp'[I:X
totalPage = totalRecords / everyPage; ceJi|`F
else ?X6}+
totalPage = totalRecords / everyPage + 1 ; ]4en|Aq
4,c6VCw3+
return totalPage; Z%B6J>;u M
} X(*O$B{
R
bNVeL$'
privatestaticboolean hasPrePage(int currentPage){ T!KwRxJ23
return currentPage == 1 ? false : true; HdI)Z<Krp
} 9%iQ~
N\ !
privatestaticboolean hasNextPage(int currentPage, /}m*|cG/
o!":mJy
int totalPage){ o#,^7ln
return currentPage == totalPage || totalPage == yvoz 3_!
7\,9Gcv1
0 ? false : true; bC1G5`v_D
} iI";m0Ny
Gw$ 5<%sB
~<n.5q%Z
} #Ir?v
0O>ClE~P
~;#}aQYo
mA+:)?e5~
ikV;]ox
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。 mL48L57Z
Q}L?o
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 yW=+6@A4
hyf
;f7`o
做法如下: 71{jedT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 A+0-pF2D
r.\L@Y<
的信息,和一个结果集List: K8&;B)VT>
java代码: c Pf_B=
#6<1
=I'j
OpEH4X.Z
/*Created on 2005-6-13*/ F. SB_S<'
package com.adt.bo; }ARA K ^%
K8_v5
import java.util.List; HT .*r6Y>g
!
I0xq"
import org.flyware.util.page.Page; 7}UG&t{
kY~4AH
/** j/*1zu8Y
* @author Joa *b.
>
*/ nJ2x;';lA
publicclass Result { P U/<7P*
i#`q<+/q
private Page page; \H@1VgmR;
c_D(%Vf5
private List content; _b~{/[s
aLGq<6Ja
/** F`QViZ'n>#
* The default constructor !{t|z=Qg
*/ #;j:;LRU
public Result(){ WI/tWj0
super(); Ec@n<KK#
} 2+
cs^M3
6p)AQTh>
/** Z)#UCoK!c
* The constructor using fields ZP<<cyY
* ^!&6=rb
* @param page J{1H$[W~}
* @param content 7~mhWPzMwB
*/ 7#0buXBg
public Result(Page page, List content){ sI!H=bp-8
this.page = page; &xQM!f
this.content = content; 3c=kYcj
} :pqUUZ6x&
,KW
Q
6
/** 9qB0F_xl
* @return Returns the content. q*l4h u%3
*/ tg/UtE`V
publicList getContent(){ TJO$r6&
return content; %M@K(Qu
} U%nkPIFm
<h7cQ
/** ,RV
qYh(-|
* @return Returns the page. _{K mj,q
*/ Cku"vVw,
public Page getPage(){ bP&QFc
return page; ixdsz\<
} 0Ds3wNz
20;9XJmjl
/** `r`8N6NQ&]
* @param content :}lqu24K
* The content to set. X g6ezlW
*/ FPDTw8" B;
public void setContent(List content){ CI'RuR3y]Z
this.content = content; iAwEnQ3h
} ^a4z*#IOr
x;n3 Zr;(
/** F)LbH&Kn
* @param page 5`QcPDp{z
* The page to set. 9{toPED
*/ <-umeY"n>
publicvoid setPage(Page page){ j~Aq-8R=
this.page = page; kOYUxr.b
} 5I622d
} s<9g3Gh
6l]X{ A.
o}OY,P
wGc7
cuhp4!!
2. 编写业务逻辑接口,并实现它(UserManager, $F2Uv\7=
dZU#lg
UserManagerImpl) iVXt@[
java代码: +xFn~b/
*;o%*:
6p9fq3~7Y
/*Created on 2005-7-15*/ HEF
e?
package com.adt.service; 8D='N`cN+
Jj"{C]
import net.sf.hibernate.HibernateException; {>f"&I<xw
nI\6aG?`
import org.flyware.util.page.Page; Y}:~6`-jj
k{}> *pCU
import com.adt.bo.Result; gxv^=;2C
f!9i6
/** 4<y
* @author Joa 8QrpNSj4
*/ 4l$OO;B
publicinterface UserManager { |kYlh5/c d
] G&*HMtp
public Result listUser(Page page)throws R6+)&:Ab{R
q&3
;e4
HibernateException; gq7tSkH@
u,sR2&Fe
} cgg6E
O(
b3ohTmy4(
YV
O$`W^N
m ptFd
/Z:j:l
java代码: No^gKh24
aSzI5J]/=
`q^#u
/*Created on 2005-7-15*/
L:$4o
package com.adt.service.impl; Bm$|XS3cD
,i2-
import java.util.List; i\i%WiRl
U\KMeaF5e-
import net.sf.hibernate.HibernateException; M.W
X&;>
NAGM3{\5v$
import org.flyware.util.page.Page; |N.2iN:
import org.flyware.util.page.PageUtil; _f1o!4ocx
A3jxjQ
import com.adt.bo.Result; D)d]o&
import com.adt.dao.UserDAO; sh<Q2X
import com.adt.exception.ObjectNotFoundException; IPQRdBQ
import com.adt.service.UserManager; (jT)o,IW&
Y6` xb`
/** 1EyN
|m|
* @author Joa _olQ;{ U:
*/ y>I2}P
publicclass UserManagerImpl implements UserManager { l5[5Y6c>
4Uy% wB
private UserDAO userDAO; =)a24PDG
cS ~OxAS
/** 3:)z+#Uk6
* @param userDAO The userDAO to set. <DF3!r
*/ qE[S>/R"
publicvoid setUserDAO(UserDAO userDAO){ 3JnpI,By
this.userDAO = userDAO; cU1o$NRx
} LP2~UVq
[h/T IGE\
/* (non-Javadoc) ;Shu
* @see com.adt.service.UserManager#listUser kp m;ohd
>Bt82ibN
(org.flyware.util.page.Page) XkaREE
*/ 1[FN: hm
public Result listUser(Page page)throws hlzB
cz*
]3KeAJ
HibernateException, ObjectNotFoundException { }A)\bffH
int totalRecords = userDAO.getUserCount(); 3BFOZV+
if(totalRecords == 0) uo9#(6
throw new ObjectNotFoundException Q]ersA8 V>
|Y9>kXM l
("userNotExist"); i'IT,jz!
page = PageUtil.createPage(page, totalRecords); g`Z=Y7jLH
List users = userDAO.getUserByPage(page); RRL{a6(?
returnnew Result(page, users); @!8aZB3odt
} jLAEHEs
z0z@LA4k6@
} Qb536RpcTY
E&M(QX5
kSAVFzUS
T5XXC1+
D6"=2XR4n
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -l^<[%
~ao:9ynY
询,接下来编写UserDAO的代码: YQBLbtn6(
3. UserDAO 和 UserDAOImpl: V6]6KP#D
java代码: [Vd$FDki
X1j8tg
6u[fCGi%
/*Created on 2005-7-15*/ 3I6ocj[,
package com.adt.dao; }vndt*F
(b&g4$!x&5
import java.util.List; d0El2Ct8
7'0Vb!(
import org.flyware.util.page.Page; kiTC)S=])
Ji4p6$ .j-
import net.sf.hibernate.HibernateException; t{md&k4
TW|K.t@5#H
/** VkQ@c;C
* @author Joa kAftW
'
*/ V9c.(QY|f
publicinterface UserDAO extends BaseDAO { <c+.%ka
1`cH
E Aa
publicList getUserByName(String name)throws 9YzV48su#
#;[G>-tC
HibernateException; [vg&E
)V
oC0ndp~+&
publicint getUserCount()throws HibernateException; 56V|=MzX]
r!:yUPv
publicList getUserByPage(Page page)throws |iM,bs
HsY5wC
HibernateException; d:kB Zrq
?UnQ?F(+G<
} Jf YgZ\#
&:&'70Ya
*z0!=>(
a_?sJ
|T:R.=R$~
java代码: 8$( I! ;
Qqm?%7A1
GZ%vFje_
K
/*Created on 2005-7-15*/ HC iRk1
package com.adt.dao.impl; V_7\VKR
P9v(5Z00|d
import java.util.List; H:fKv7XL
I}C2;[a B
import org.flyware.util.page.Page; v$ ti=uk$
(x=$b(I
import net.sf.hibernate.HibernateException; 7KC>?F
import net.sf.hibernate.Query; @G5T8qwN
VjQ&A#
import com.adt.dao.UserDAO; H 0l1=y
HNzxFnh
/** )[rVg/m
* @author Joa vsGKCrLwh
*/ Al>d
21U
public class UserDAOImpl extends BaseDAOHibernateImpl qBEp |V
p9v:T1?
implements UserDAO { 7=-Yxt
8>KUx]AN
/* (non-Javadoc) =uP?
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* @see com.adt.dao.UserDAO#getUserByName (bwD:G9
B[b>T=
(java.lang.String) +kSu{Tc
*/ (_FU3ZW!
publicList getUserByName(String name)throws YT(N][V
kx,.)qKk
HibernateException { =p5DT
String querySentence = "FROM user in class <-VBb[M#
s.J4&2Q
com.adt.po.User WHERE user.name=:name"; c^}y9% 4c
Query query = getSession().createQuery rA~f68h|
Z?)g'n
(querySentence); 7;jD>wp9D
query.setParameter("name", name); "O34 E?ql.
return query.list(); l=?e0d>O
} (< +A w7
(Pc>D';{S
/* (non-Javadoc) pz%s_g'
* @see com.adt.dao.UserDAO#getUserCount() Af3|l
*/ 3$?6rMl@y
publicint getUserCount()throws HibernateException { bzr2Zj{4
int count = 0; ]$smFF
String querySentence = "SELECT count(*) FROM 'ZbWr*bo
*HoRYCL
user in class com.adt.po.User"; 4]o+)d.`(
Query query = getSession().createQuery Y'U1=w~E
nCQtn%j't
(querySentence); }g bLWx'iG
count = ((Integer)query.iterate().next o/pw=R/):
z,,"yVk`,
()).intValue(); OBi(]l}^O
return count; YR?Y:?(
} T$;S
';C'9k<P:
/* (non-Javadoc) \jfK']P/H
* @see com.adt.dao.UserDAO#getUserByPage (/:m*x*6
{JE [
(org.flyware.util.page.Page) {4J.
*/ U1 _"D+XB
publicList getUserByPage(Page page)throws VbX P7bZ
]Lv3XMa
HibernateException { hRf
l\Q[
String querySentence = "FROM user in class u/=hueR<^
g p:0 Y
com.adt.po.User"; L
FWp}#%
Query query = getSession().createQuery lV\iYX2#
1K Vit{
(querySentence); WvfP9(-
query.setFirstResult(page.getBeginIndex()) (*S<2HN5
.setMaxResults(page.getEveryPage()); Am,{Fj
return query.list(); +?J N_aR
} 9$)&b\D
JL M Xkcc
} =gVMt
}UPC~kC+Z
t^01@ejM+
3](hMk,}
/.]u%;%r[
至此,一个完整的分页程序完成。前台的只需要调用
2%@tnk|@
Z^kE]Ir#EV
userManager.listUser(page)即可得到一个Page对象和结果集对象 A8-[EBkK
8~Kq"wrbu
的综合体,而传入的参数page对象则可以由前台传入,如果用
SkjG}
2uj
.*
webwork,甚至可以直接在配置文件中指定。 HE&)N
clY
~1O|4mssS
下面给出一个webwork调用示例: \F|)w|v
java代码: '+9<[]
DzVCEhf
$1.-m{Bd
/*Created on 2005-6-17*/ HV a9b;
package com.adt.action.user; V0;"Qa@q
7_\G|Zd
import java.util.List; $;^|]/-
lOm01&^"E
import org.apache.commons.logging.Log; vl:~&I&y;R
import org.apache.commons.logging.LogFactory; 9]eG|LFD
import org.flyware.util.page.Page; 7O55mc>cF
x?L0R{?WW
import com.adt.bo.Result; gmVN(K}SR5
import com.adt.service.UserService; a2P)@R
import com.opensymphony.xwork.Action; NjIPHM$g
TAG@Ab
/** wV )\M]@
* @author Joa Ph^1Ko"2
*/ u+8"W[ZULq
publicclass ListUser implementsAction{ \,13mB6
'8 .JnCg
privatestaticfinal Log logger = LogFactory.getLog 2Mx\D
Ta\F~$M
(ListUser.class); u8c@q'_
Sr
\y1nt
private UserService userService; ;"M6}5dQ4
d88A.Z3w
private Page page; 9~hW8{#
p{,#H/+J
privateList users; ny
KfM5s_
k]p|kutQCy
/* jSjC43lh
* (non-Javadoc) 0/v]YK.
* Z5t^D|
* @see com.opensymphony.xwork.Action#execute() _y4O2n[e
*/ [H*JFKpx
publicString execute()throwsException{ &g;!n&d zP
Result result = userService.listUser(page); .jJD$FC
page = result.getPage(); .57p4{
users = result.getContent(); e]VW\6J&
return SUCCESS; c^I^jg2v
} Bz/ba *
7(}'jZ
/** lTC0kh
* @return Returns the page. ao)';[%9s
*/ Gwk$<6E
public Page getPage(){ ,8r?C !m]
return page; C:Jfrg`
} YrnC'o`
DgT]Nty@b
/** 5Npxs&Ea
* @return Returns the users. PA'&]piPl:
*/ x'g4DYl
publicList getUsers(){ -J3~j kf
return users; *H!BThft4
} 4x6n,:;
*QQeK#$s
/** /0}Z>iK
* @param page uXc;!*
* The page to set. *47/BLys<
*/ G QYR`;>
publicvoid setPage(Page page){ u\Cf@}5(
this.page = page; M{ncWq*_j
} <&m50pq
Z3&}C h
/** wp@_4Iq1$
* @param users (iq>]-=<
* The users to set. |Y
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*/ &{e ]S!D
publicvoid setUsers(List users){ ulxlh8=
this.users = users; ;qaPK2a8
} :(]fC~G~
pq`uB
/** x|m9?[
!_
* @param userService >
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* The userService to set. 6FzB-],
*/ ^2-
<XD)
publicvoid setUserService(UserService userService){ WO.u{vW]'
this.userService = userService; P<IDb%W
} Bf*>q*%B{
} l WYp
?#w} S%
ktrIi5B
Xr
<H^X
l_}d Q&R
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, *b>RUESF
`,6|6.8#
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 9^F3r]bH
qHZDo[
么只需要: %>$<s<y
java代码: bB?E(>N;
>eA@s}_8
{_N9<i{T
<?xml version="1.0"?> wPM&N@Pf
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork HaVhdv3L
j Mn,N9Mf
1.0//EN" "http://www.opensymphony.com/xwork/xwork- u{DEOhtI4
estiS
1.0.dtd"> ~5+RK16
%rb$tKk
<xwork> 9nN1f@Y
d%|l)JF*5
<package name="user" extends="webwork- n725hY6}<l
~1+6gG
interceptors"> 8</wQ6&|
J'Pyn
<!-- The default interceptor stack name vS\ 2zwb}
T[$-])iK
--> -8^qtB
<default-interceptor-ref <-k!
C7S\4rDJ
name="myDefaultWebStack"/> hY.i`sp*/
3q'AgiW
<action name="listUser" d~~kJKK
e4` L8
class="com.adt.action.user.ListUser"> _;03R{e*
<param ZxNTuGOB:
5;}W=x^$a
name="page.everyPage">10</param> k^Qf |
<result N#l2wT
?)1Y|W'Rv
name="success">/user/user_list.jsp</result> d9$RmCHe}
</action> J[<Zy^"Y;
jTR?!Mt0
</package> O?X[&t
+7b8 ye
</xwork> _nqnO8^IG4
y;ElSt;S
:C>7HEh-2_
;v.[aq
i3,.E]/wX@
O=3/qs6m
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 \I!mzo
JVuju$k
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。 nmU1xv_
'|4+<#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 D[yyFo,z
]$ "eGHX
8NHm#Z3Ol
LJ[zF~4#
B)Y[~4o
我写的一个用于分页的类,用了泛型了,hoho MOD&3>NI
=3X>Ur
java代码: M<Wi:r:
F_*']:p
W q<t+E[
package com.intokr.util; ,Iyc0
.j:,WF<"l5
import java.util.List; w5 . ^meU
G[mqLI{q
/** Lyhuyb)k5^
* 用于分页的类<br> ?CAU+/
* 可以用于传递查询的结果也可以用于传送查询的参数<br> a|FkU%sjzZ
* 5e+j51
* @version 0.01 !ekByD
* @author cheng #zl1#TC{(
*/ (S!UnBb&
public class Paginator<E> { `2 <:$]
privateint count = 0; // 总记录数 itzUq,T
privateint p = 1; // 页编号 FC1rwXL(
privateint num = 20; // 每页的记录数 B!/kC)bF:
privateList<E> results = null; // 结果 =R=V
_BP%@o
/**
^f,4=-
* 结果总数 2?~nA2+vm
*/ $YX{gk>
publicint getCount(){ 6X@z(EEL
return count; 4"2%mx:
} bX$z)]KKu
WRD
z*Zf
publicvoid setCount(int count){ {c*$i^T
this.count = count; r)|~Rs!y,
} LWM<[8wJ4
ya&=UoI
/** YcA. Bn|as
* 本结果所在的页码,从1开始 %k#+nad
* w<H Xe
* @return Returns the pageNo. qO"QSSbZqQ
*/ BsFO]F5mmX
publicint getP(){ s^zlBvr|.
return p; IMWt!#vuY
} dT0W8oL
sLA.bp.O
/** 4<($ZN8
* if(p<=0) p=1 ^^v3iCT
* J,Ki2'=
* @param p 50MM05aC
*/ Tm`@5
publicvoid setP(int p){ rT `sY
if(p <= 0) fDs T@W,K
p = 1; Bb=r?;zjO
this.p = p; lf`ULY4{
} [k$GUU,jY
lWc[Q1
/** nDvfb*\
* 每页记录数量 sc]#T)xG
*/ qefp3&ls
publicint getNum(){ Doc zQc-U+
return num; }K) AjZ
} tCrEcjT-
0Ye/
/** IIAp-Y~B
* if(num<1) num=1 W_wC"?A%
*/ \NNA"
publicvoid setNum(int num){ eA1g}ipm
if(num < 1) ~+' f[!^
num = 1; ^Z)7Z%
O
this.num = num; W$jRS
} )"\=
_E#
W%+02_/)
/** X.#*+k3s0
* 获得总页数 !ldEy#"X
*/ _qE9]mU
publicint getPageNum(){ F qJ`d2E
return(count - 1) / num + 1; vT#R>0@mi
} q%G[tXw
B5 /8LEWw
/** "1gIR^S%9
* 获得本页的开始编号,为 (p-1)*num+1 7D<Aa?cv_l
*/ "=Z=SJ1D
publicint getStart(){ h~Ir=JV
return(p - 1) * num + 1; P1OYS\
} drAJ-ii
(.$$U3\
/** YQD`4ND
* @return Returns the results. Z><+4
'
*/ )$p36dWl
publicList<E> getResults(){ 3_@IE2dA
return results; yreH/$Ou8
} 0 @#Jz#?
oPs asa
public void setResults(List<E> results){ 9 5!xJdq
this.results = results; ED8{
} (tA[] ne2
+On2R&m
public String toString(){ imADjBR]
StringBuilder buff = new StringBuilder 1CJ1-]S(3
#*:1C h]B
(); <q'?[aKvR
buff.append("{");
zr ez*
buff.append("count:").append(count); y3(~8n
buff.append(",p:").append(p); rWWpP<
buff.append(",nump:").append(num); NdJ]\>5oN,
buff.append(",results:").append \
3E%6L
\#biwX
(results); #.u&2eyqQ
buff.append("}"); {KSLB8gtL
return buff.toString(); roZn{+f
} f]10^y5&
yx#!2Z0hw
} }{:Jj/d
p
~Q"qz<WO
!]R>D{""