Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N`3^:EJL8
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n
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TA:uB[Ji
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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 fE&s 6w&
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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 r:E4Wi{\
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。 6BEpnw>p(
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分页支持类: a\oz-`ESa
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java代码: =1(7T.t
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package com.javaeye.common.util; v^F00@2I
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import java.util.List; 5JK'2J&
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publicclass PaginationSupport { eH!V%dX
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publicfinalstaticint PAGESIZE = 30; 2QEH!)lvr
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privateint pageSize = PAGESIZE; *A8Et5HAv
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privateList items; :RJo#ape
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privateint totalCount; _3wK: T{:
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privateint[] indexes = newint[0]; T<b*=i
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privateint startIndex = 0; $cwmfF2C
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public PaginationSupport(List items, int o"z;k3(i$7
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totalCount){ hA1B C3
setPageSize(PAGESIZE); Z]bG"K3l
setTotalCount(totalCount); {<gX~./]c
setItems(items); e{Vn{.i,5
setStartIndex(0); ,F`1VpTd8
}
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public PaginationSupport(List items, int &V SZ
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totalCount, int startIndex){ `d4xX@
setPageSize(PAGESIZE); x
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setTotalCount(totalCount); gd#?rc*f<3
setItems(items); ;L#RFdh
setStartIndex(startIndex); B]}gfVO
} a}|<*!4zUQ
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public PaginationSupport(List items, int |O'*CCrCL
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totalCount, int pageSize, int startIndex){ F$|:'#KN
setPageSize(pageSize); ;mz#$"(
setTotalCount(totalCount); F2_'U' a
setItems(items); #f_'&m
setStartIndex(startIndex); h6<i,1gQ1
} ^`aw5 +S
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publicList getItems(){ =2DK?]K;
return items; BhbfPQ
} tlg}"lY
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publicvoid setItems(List items){ aaN/HE_
this.items = items; .3n\~Sn
} i O? f&u
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publicint getPageSize(){ ?$tD
return pageSize; L]"$dF
} qdKqc,R1{
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publicvoid setPageSize(int pageSize){ 5 $$Cav
this.pageSize = pageSize; X%JyC_~<
} ].aFdy
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publicint getTotalCount(){ I*(kv7(c0
return totalCount; n_ ?+QF
} yD.(j*bMK;
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publicvoid setTotalCount(int totalCount){ G,^ ?qbHg
if(totalCount > 0){ m^m=/'<+
this.totalCount = totalCount; *icaKy3
int count = totalCount / n+Conp/
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pageSize; x5pu+-h
if(totalCount % pageSize > 0) `'3 De(
count++; c(FGW7L<
indexes = newint[count]; -r_\=<(
for(int i = 0; i < count; i++){ :"Tkl$@,
indexes = pageSize * 89{;R
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i; KSEKoHJo
} }U5$~,*p
}else{ be]/ROP>H
this.totalCount = 0; 3&{6+ A
} sKR%YK
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} F s=x+8'M
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publicint[] getIndexes(){ !Y7$cU &
return indexes; y!R9)=/M
} qxHn+O!h
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publicvoid setIndexes(int[] indexes){ _?'W30Dg
this.indexes = indexes; ;pOV; q3j
} "*l{ m2"
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publicint getStartIndex(){
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return startIndex; WS.g`%
} P_8!Gp
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publicvoid setStartIndex(int startIndex){ )8}k.t>'s
if(totalCount <= 0) WJa7
this.startIndex = 0; Z,O-P9jC
elseif(startIndex >= totalCount) wTZ(vX*mK
this.startIndex = indexes %Ny1H/@Q1+
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[indexes.length - 1]; 7F~g A74h
elseif(startIndex < 0) ;qbK[3.
this.startIndex = 0; /k RCCs8t}
else{ 52Dgul
this.startIndex = indexes <
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[startIndex / pageSize];
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} u(f;4`
} +|pYu<OY
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publicint getNextIndex(){ ~OxFgKn23&
int nextIndex = getStartIndex() + ZPq.|6&
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pageSize; p8YOow7)
if(nextIndex >= totalCount) Ik5V?
return getStartIndex(); ohJDu{V
else c{?SFwgd
return nextIndex; ,C0y3pL
} 6w
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publicint getPreviousIndex(){ Q2woCxB
int previousIndex = getStartIndex() - 3c wBPqH
#;@I.
pageSize; ~EXCYUp4v
if(previousIndex < 0) 2Kr>93O
return0; <}8G1<QZ'.
else S0:Oep
return previousIndex; k&f/f
} ]F>#0Rdc
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} Mk973'K'
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抽象业务类 g`C8ouy
java代码: W_ Hoa*~
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/** s] ;P<
* Created on 2005-7-12 D2gyn-]\
*/ um_J%v6ER
package com.javaeye.common.business; " Qyi/r41
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import java.io.Serializable; Jq? zr]"A
import java.util.List; a'Zw^g
Wc!]X.|9*
import org.hibernate.Criteria; HyKA+7}
import org.hibernate.HibernateException; 1n7'\esC*
import org.hibernate.Session; $G }9iV7
import org.hibernate.criterion.DetachedCriteria; h# Z,ud_
import org.hibernate.criterion.Projections; }m5()@Q}a
import P{_%p<:V
M3F1O6=4j
org.springframework.orm.hibernate3.HibernateCallback; K[/L!.Ag
import :?FHqfN?_
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org.springframework.orm.hibernate3.support.HibernateDaoS Y}t)!}p$r
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upport; _FcTY5."S
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import com.javaeye.common.util.PaginationSupport; ZUS5z+o
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public abstract class AbstractManager extends ,RY;dX-#
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HibernateDaoSupport { W(4$.uZ)
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privateboolean cacheQueries = false; CQa8I2VF
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privateString queryCacheRegion; LYd:S
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publicvoid setCacheQueries(boolean xJU]py~o
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cacheQueries){ S&XlMu
this.cacheQueries = cacheQueries; 6\I1J=
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} 6J}Yr5oD
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publicvoid setQueryCacheRegion(String =>evkaj
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queryCacheRegion){ r@vt.t0#
this.queryCacheRegion = g"kI1^[nj
tu* uQ:Ipk
queryCacheRegion; PUZcb+%]h
} .oT'(6#
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publicvoid save(finalObject entity){ *mJ#|3I<
getHibernateTemplate().save(entity); = _N[mR^
} J` gG`?
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publicvoid persist(finalObject entity){ (y&sUc9
getHibernateTemplate().save(entity); SDE$ymPx
} GRkN0|ovfj
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publicvoid update(finalObject entity){ 9Oq(` 4
getHibernateTemplate().update(entity); |K{d5\_
} c?. i;4yh
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publicvoid delete(finalObject entity){ tK/,U
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getHibernateTemplate().delete(entity); (EosLn
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} Rf>)#hn%
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publicObject load(finalClass entity, kN{$-v=K
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finalSerializable id){ A?}[rM
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return getHibernateTemplate().load P:vp/x!
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(entity, id); +WMXd.iN,
} !QbuOvw
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publicObject get(finalClass entity, ` V [4
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finalSerializable id){ oA7DhU5n
return getHibernateTemplate().get 2@
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(entity, id); <DR!AR)
} _Y]Oloo('
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publicList findAll(finalClass entity){ GQhy4ji'z
return getHibernateTemplate().find("from ^dhx/e%s
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" + entity.getName()); ~TS!5Wiv
} MusUgBQy
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publicList findByNamedQuery(finalString Sa[lYMuB
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namedQuery){ tD}-&"REP
return getHibernateTemplate 6B7*|R>
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().findByNamedQuery(namedQuery); c^pQitPv
} "Ueq
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publicList findByNamedQuery(finalString query, P!IA;i
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finalObject parameter){ 4u%AZ<-C}m
return getHibernateTemplate +75"Q:I
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().findByNamedQuery(query, parameter); D&uaA-;s
} [M%?[E}>
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publicList findByNamedQuery(finalString query, +>*=~R
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finalObject[] parameters){ 4K7ved)
return getHibernateTemplate W#NZnxOX"
\#Jq%nd
().findByNamedQuery(query, parameters); -=gI_wLbM
} x7<l*WQ
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publicList find(finalString query){ v^s?=9
return getHibernateTemplate().find pL;e(lM
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(query); MD<x{7O12>
} Db*b"/]
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publicList find(finalString query, finalObject A- Abj'
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parameter){ JeNX5bXW
return getHibernateTemplate().find /}6y\3h
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(query, parameter); G/#<d-}_
} f"*4R
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public PaginationSupport findPageByCriteria k\T]*A
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(final DetachedCriteria detachedCriteria){ Q(yg bT
return findPageByCriteria !^98o:"x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); YzM/?enK}T
} :{Z%dD
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public PaginationSupport findPageByCriteria 8N9,HNBT$
N}7b^0k
(final DetachedCriteria detachedCriteria, finalint 0n`Temb/
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startIndex){ Hf_
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return findPageByCriteria sn^ 3xAF
.|07IH/Di{
(detachedCriteria, PaginationSupport.PAGESIZE, ~Y*.cGA
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startIndex); c7@/<*E+
} kv2o.q
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public PaginationSupport findPageByCriteria \I4Uj.'>\
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(final DetachedCriteria detachedCriteria, finalint g4Dck4^!4
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pageSize, O NcLhwH
finalint startIndex){ _ eBNbO_J
return(PaginationSupport) \_R<Q?D+
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getHibernateTemplate().execute(new HibernateCallback(){ k{F6WQ7
publicObject doInHibernate 0Qvr
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(Session session)throws HibernateException { #4LTUVH
Criteria criteria = Op~:z<z
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detachedCriteria.getExecutableCriteria(session); Lk#)VGk:
int totalCount = u #}1
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((Integer) criteria.setProjection(Projections.rowCount PX&}g-M9
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()).uniqueResult()).intValue(); _:tS-Mx@5
criteria.setProjection A&v Qtd
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(null); (0LA.aBIf
List items = 'sa)_?Hy
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criteria.setFirstResult(startIndex).setMaxResults 4Y1^ U{A+
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(pageSize).list(); ^z,B}Nz
PaginationSupport ps = S["r
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new PaginationSupport(items, totalCount, pageSize, CW8YNJ'
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startIndex); 5?
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return ps; /@&o%I3h
} :]Om4Q\-#
}, true); =B;qy7?
} upk_;ae
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public List findAllByCriteria(final 7^! zT
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DetachedCriteria detachedCriteria){ s/11TgJ
return(List) getHibernateTemplate w?nSQBz$
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().execute(new HibernateCallback(){ $qZ6i
publicObject doInHibernate |HY{Q1%
=1|p$@L`%
(Session session)throws HibernateException { 55<!H-zt
Criteria criteria = )*uo tV
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detachedCriteria.getExecutableCriteria(session); >>C
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return criteria.list(); zlQBBm;fE
} "o u{bKe
}, true); i-4L{T\K
} 2MYez>D
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public int getCountByCriteria(final eA?|X|
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DetachedCriteria detachedCriteria){ eA
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Integer count = (Integer) x]%,?Vd?
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getHibernateTemplate().execute(new HibernateCallback(){ \k=%G_W
publicObject doInHibernate Oz]$zRu/0
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(Session session)throws HibernateException { M($GZ~ b%A
Criteria criteria = 0Db=/sJ>
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detachedCriteria.getExecutableCriteria(session); zYdieE\-
return &%/T4$'+Y+
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criteria.setProjection(Projections.rowCount G
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()).uniqueResult(); eUR+j?5I
} N;!!*3a9=
}, true); 8$iHd
return count.intValue(); 7)RvBcM
} OuWRLcJ!
} &P35\q
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用户在web层构造查询条件detachedCriteria,和可选的 6iEg]FI
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 !>Q\Y`a,*
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PaginationSupport的实例ps。 ? }`mQ <~
aAn p7\7
ps.getItems()得到已分页好的结果集 017n hI
ps.getIndexes()得到分页索引的数组 8o
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ps.getTotalCount()得到总结果数 6jm/y@|F!
ps.getStartIndex()当前分页索引 u%"5<ll
ps.getNextIndex()下一页索引 ;Kg7}4`I
ps.getPreviousIndex()上一页索引 D97 vfC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 W.D>$R2
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 .VUnOdI
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一下代码重构了。 -GB,g=Dk
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我把原本我的做法也提供出来供大家讨论吧: a gL@A
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首先,为了实现分页查询,我封装了一个Page类: >$r o\/
java代码: Qr6PkHU
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/*Created on 2005-4-14*/ wPcEvGBN=
package org.flyware.util.page; 7xG~4N<)]
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/** MTNC{:Q
* @author Joa ,\RR@~u'
* jPx}-_jM
*/ {L.uLr_?e
publicclass Page { _nX8f
&
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/** imply if the page has previous page */ #!#s7^%K&
privateboolean hasPrePage; @+y,E-YTdV
m] -cRf)9
/** imply if the page has next page */ 3r,Kt&2$
privateboolean hasNextPage; V 7ZGT
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/** the number of every page */ <viC~=k;
privateint everyPage; >XM]UdP
:Y9/} b{
/** the total page number */ IAe/)
privateint totalPage; qss)5a/x.
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/** the number of current page */ )_4()#3
privateint currentPage; MtoOIkQ
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xx
/** the begin index of the records by the current P6'Se'f8
qTMY]=(
query */ p:0X3?IG3
privateint beginIndex; E2>+V{TF
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/** The default constructor */ x5/&,&m`%
public Page(){ /s=veiH
~ ^
} [/n@BK
A%^7D.j
/** construct the page by everyPage }owl7G3
* @param everyPage *BF[thB:a
* */ L*vKIP<EMM
public Page(int everyPage){ gA@Zx%0j
this.everyPage = everyPage; ]T2Nr[vu
} L<Z,@q`
n"Bc2}{
/** The whole constructor */ :rjfAe=s
public Page(boolean hasPrePage, boolean hasNextPage, apfr>L3
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(vchZn#
int everyPage, int totalPage, +"k?G
int currentPage, int beginIndex){ ?~yJ7~3TS<
this.hasPrePage = hasPrePage; 5wl;fL~e
this.hasNextPage = hasNextPage; #5'&
|<
this.everyPage = everyPage; ``6-
this.totalPage = totalPage; Nv6"c<(L=
this.currentPage = currentPage; <dr2 bz
this.beginIndex = beginIndex; D&~%w!
} Vry_X2
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/** g0B%3v
* @return ,_,*I/o>B
* Returns the beginIndex. YgS,5::SU
*/ 1)zXv
publicint getBeginIndex(){ 4i+%~X@p
return beginIndex; LNHi}P~
} K'
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jI H^
/** Dh?I
* @param beginIndex W7!iYxO
* The beginIndex to set. u|.7w2
*/ Ek6g?rj_
publicvoid setBeginIndex(int beginIndex){ c/v|e&q
this.beginIndex = beginIndex; o;
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} N3@[95
g-"G Zi
/** MtN!Xx
* @return $60`Hh 4/
* Returns the currentPage. >V)"TZH
*/ gw[Eu>I
publicint getCurrentPage(){ !@N?0@$/
return currentPage; uN>5Eh&=Pf
} h8(>$A-
Pw thYy
/** 0\B{~1(^
* @param currentPage 0_MtmmL.
* The currentPage to set. RtpV08s\
*/ W g6H~x
publicvoid setCurrentPage(int currentPage){ iemp%~UZ
this.currentPage = currentPage; $gD8[NAIx=
} z0SF2L H
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/** N2duhI6
* @return V %D1Q}X
* Returns the everyPage. nb<o o:^
*/ jC{KI!kPt
publicint getEveryPage(){ K5BL4N
return everyPage; #d-zH:uq
} eNVuw: Q+
u'>94Gm}
/** TB+k[UxB
* @param everyPage k,k>w#&
* The everyPage to set. P R3Arfle
*/ AovBKB
$
publicvoid setEveryPage(int everyPage){ zp<B,Ls
this.everyPage = everyPage; vlE]RB
} 7}6CUo
ms&1P
/** +{V`{'
* @return v~x4Y,m%
* Returns the hasNextPage. OHsA]7S
*/ #RaqNu
publicboolean getHasNextPage(){ |('o g *$
return hasNextPage; X:;x5'|
} jnTTj l
}zQgS8PQH
/** 3,6f}:CG
* @param hasNextPage NlKVl~_ C
* The hasNextPage to set. U&Vu%+B
*/ gD4vV'|
publicvoid setHasNextPage(boolean hasNextPage){ dpylJ2
this.hasNextPage = hasNextPage; 18QqZ,t
} uW=G1 *n-
=r7!QXPH}
/** :/$WeAg
* @return `?3f76}h
* Returns the hasPrePage. ThI}~$Y
*/ X~D[CwA|`
publicboolean getHasPrePage(){ $8%"bR;Hu
return hasPrePage; Y<irNp9
} f pq|mY
6uFw+Ya#
/** -bHlFNRm
* @param hasPrePage /(51\RYkir
* The hasPrePage to set. 'hs4k|B
*/ aK@
Y) Ju'
publicvoid setHasPrePage(boolean hasPrePage){ t(uvc{K*
this.hasPrePage = hasPrePage; }^&f {
} PgT8
1u
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/** =f{v:n6
* @return Returns the totalPage. '6&o:t
* 1(IZ,*i
*/ v
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publicint getTotalPage(){ d!0rq4v7
return totalPage; .7gh2K
} WK(X/!1/k
UgS`{&b36
/** -8Mb~Hfl0
* @param totalPage Ue
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* The totalPage to set. rpm \!O
*/ "IT7.!=@9
publicvoid setTotalPage(int totalPage){ %gAT\R_f
this.totalPage = totalPage; Y'iyfnk
} Xi[]8o
n>j2$m1[
} Q/
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j_N<aX
j7kX"nz
kF~(B]W(
k/wD@H N
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 qfE0J;e
6Uk+a=Ar
个PageUtil,负责对Page对象进行构造: 7`;sX?R
java代码: W
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K8X7IE
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/*Created on 2005-4-14*/ 9AX}V6\+
package org.flyware.util.page; n2B%}LLa
1?FG3X 5
import org.apache.commons.logging.Log; DMG~56cTO,
import org.apache.commons.logging.LogFactory; Jp]?tlT
KxX [8
/** yef\Y3X
* @author Joa _Ik?WA_;
* bAZoi0LR
*/ kP&I}RY
publicclass PageUtil { ^py=]7[I
ya8p
4N{_
privatestaticfinal Log logger = LogFactory.getLog 9Sxr9FLW~
6Qt(Yu*s
(PageUtil.class); [_(J8~va
@NRN#~S,_]
/** aX;>XL4
* Use the origin page to create a new page NknS:r&2
* @param page B=a+cT
* @param totalRecords )
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* @return )/;+aDk
*/ 1~L;S
publicstatic Page createPage(Page page, int fOHbgnL>
&`l\Q\_[@
totalRecords){ B&6NjLV
return createPage(page.getEveryPage(), =?6c&Z
@9HRGxJ=}
page.getCurrentPage(), totalRecords); :
"|/
} fc*>ky.v
1 #,4P1"
/** rx gSQ+G_
* the basic page utils not including exception 9,INyEyAL
B\RAX#
handler Zpkd8@g@
* @param everyPage =eU=\td^
* @param currentPage vY m:V:7Y2
* @param totalRecords Za{O9Qc?D|
* @return page /f1]U
LmC:
*/ Q/4-7
publicstatic Page createPage(int everyPage, int @c]KHWI
{S{ %KkAV
currentPage, int totalRecords){ rzAf {2
everyPage = getEveryPage(everyPage); m1pA]}Y/5o
currentPage = getCurrentPage(currentPage); @-dGZ5
int beginIndex = getBeginIndex(everyPage, 9m)$^U>oz
Hp=BnN
currentPage); -a)1L'R
int totalPage = getTotalPage(everyPage, hi!A9T3%}M
;^xM"
{G8
totalRecords); $C7a#?YF,
boolean hasNextPage = hasNextPage(currentPage, +Pl)E5W!=`
:6nD "5(
totalPage); qhGz2<}_j
boolean hasPrePage = hasPrePage(currentPage); _HHvL=
HXKM<E{j
returnnew Page(hasPrePage, hasNextPage, 6T$=(I <4
everyPage, totalPage, ,yltt+e
currentPage, AyO%,6p[
i#*[,
P~
beginIndex); KBB)xez8
} e^O:I
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privatestaticint getEveryPage(int everyPage){ r&4Xf#QD6
return everyPage == 0 ? 10 : everyPage; =;0-t\w!
} DH?n~qKpC
@FN|=?8%
privatestaticint getCurrentPage(int currentPage){ nKm#
kb
return currentPage == 0 ? 1 : currentPage; a*5KUj6/TL
} }9"''Z
)&1v[]%S
privatestaticint getBeginIndex(int everyPage, int ^H.B6h?
Fa>f'VXx
currentPage){ l{dsm1#W~
return(currentPage - 1) * everyPage; 9?,i+\)qK@
} >wh v*@Fr
OK80-/8HI
privatestaticint getTotalPage(int everyPage, int "++\6H<
1@L18%h
totalRecords){ n/5T{ NfG
int totalPage = 0; O.B9w+G=
2/4zg
if(totalRecords % everyPage == 0) t<` As6}
totalPage = totalRecords / everyPage; p$\>3\
else ]oV{JR]
totalPage = totalRecords / everyPage + 1 ;
b M1\z
|iHMAo
return totalPage; g& e u
} EU[eG^/0@
bIiuna\
privatestaticboolean hasPrePage(int currentPage){ J]TqH`MA
return currentPage == 1 ? false : true; _l7_!Il_
} `Jc/ o=]
?2&= +QaT
privatestaticboolean hasNextPage(int currentPage, dHIk3j-!
S3Y.+. 0U
int totalPage){ GmR3
a
return currentPage == totalPage || totalPage == e El)wZ,A
$,~Ily7w
0 ? false : true; jvB[bS`<H
} U)8yd,qG[%
.m]}Ba}J$
pZ>yBY?R8>
} _ARG
"
BFW b0;+
%!nI]|
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R#hy2kA
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。 PN 93.G(W
vQ*[tp#qU
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 0fewMS*
FJZ'P;3
做法如下: i1uoYb?4(I
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~".@mubt1$
I.3~ctzu
的信息,和一个结果集List: s0' haU
java代码: 32 i6j
7{}E{/
7_2D4CI
/*Created on 2005-6-13*/ sg7h&<Xx
package com.adt.bo; CnB[ImMs(A
j<~Wp$\i7>
import java.util.List; 3FR(gr$X
SQ,-45@W
import org.flyware.util.page.Page; -kk7y
G~1;_'
/** T MMKRC1<
* @author Joa !=:>y WQ
*/ \B4H0f
publicclass Result { id:,\iJ
yo#r^iAr
private Page page; ] x)>q
AT1cN1:4?
private List content; R/v|ZvI
u&Ic
/** p*c(dkOe8
* The default constructor N]
sbI)Z@
*/ &AJ bx
public Result(){ Y|LL]@Lv
super(); k";dK*hD,
} O z0-cM8t
H*N <7#
/** P6GTgQ<'BA
* The constructor using fields ooJxE\L
* M^ '1Q.K
* @param page .9vS4C
* @param content >;4q
*/ .5Y{Yme
public Result(Page page, List content){ z]N#.utQ
this.page = page; U*a#{C7"
this.content = content; {%3WHGr%L
} |V\{U j
Jai]z
/** 90}vFoy
* @return Returns the content. AF#:*<Ev
*/ ysOf=~1
publicList getContent(){ [nxYfER7
return content; ~JT2el2W7p
} 8~O#@hB~3
I]eeV+U8W
/** E'\gd7t ;
* @return Returns the page. t[q2W"#.
*/ y7UU'k`
public Page getPage(){ xH2'PEjFM
return page; GG>53}7{
} #[M^Q
h
ywp_,j9F
/** fSbLkd 9
* @param content j:cu;6|
* The content to set. t/t6o&
*/ #|E#Rkw!
public void setContent(List content){ 6ZIPe~`
this.content = content; 01@WU1IN
} S Q:H2vvD
:0y-n.-{
/** >!1]G"U
* @param page s;bGg
* The page to set. AHs%?5YTY;
*/ enPtW
publicvoid setPage(Page page){ !LH;K
this.page = page; lx2#C9L_
} /4Wf\
Zu
} g
sm%4>sc
R8[VD iM6E
0 8L;u7u
tkV[^OeU>
#D_Ti%.^}
2. 编写业务逻辑接口,并实现它(UserManager, K{_~W yRF
liYsUmjZ=
UserManagerImpl) Vw w 211
java代码: z+.G>0M
VL*5
\9,lMK[b
/*Created on 2005-7-15*/ OulRqbL2
package com.adt.service; ?M'CTz}<\
|[n\'Xy;{
import net.sf.hibernate.HibernateException; --y,ky#
Pa{DB?P
import org.flyware.util.page.Page; g"sb0d9
/ZiMD;4@y
import com.adt.bo.Result; lB _9b_|2
Z]Xa:[
/** qGag{E5!
* @author Joa YL*FjpVW
*/ >A D!)&c
publicinterface UserManager { #8t=vb3
XwEMF5[
public Result listUser(Page page)throws hub]M
Ch?yk^cY
HibernateException; iyCH)MA
x=rMjz-`_
} z#RwgSPw6
MX~h>v3_R4
\
&|xMw[
'KmM%tN
7|=SZ+g
java代码: !Dc?9W!b
$xW9))
GjEV]hqR
/*Created on 2005-7-15*/ C4E}.``Hm
package com.adt.service.impl; S".|j$
<P1nfH
import java.util.List; R5b,/>^'A
pqs!kSJV
import net.sf.hibernate.HibernateException; 0UpRSh)#
+>1Yp"> ?
import org.flyware.util.page.Page; %62|dhl6
import org.flyware.util.page.PageUtil; ([$KXfAi]h
)xc1Lsrr9
import com.adt.bo.Result; axnVAh|}S
import com.adt.dao.UserDAO; 9u=]D> kb
import com.adt.exception.ObjectNotFoundException; JT}"CuC
import com.adt.service.UserManager; x!I@cP#O
Wp
=
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/** Z5rL.a&
* @author Joa ^'N!k{x
*/ |7|'JTy
publicclass UserManagerImpl implements UserManager { wIRU!lIF9
dW/(#KP/+
private UserDAO userDAO; ) %Xp?H_
_@\-`>J
/** xM)P=y_!M+
* @param userDAO The userDAO to set. @&HLm^j2O
*/ &:d`Pik6
publicvoid setUserDAO(UserDAO userDAO){ zLr:zf l
this.userDAO = userDAO; ~yN>9f U
} eYRd#w
Zu#^a|PE*
/* (non-Javadoc) vKoQ!7g
* @see com.adt.service.UserManager#listUser 'GW~~UhdW
}c9RDpjh~
(org.flyware.util.page.Page) }:?_/$};
*/ D'g@B.fXd
public Result listUser(Page page)throws lnl>!z
8}oe))b
HibernateException, ObjectNotFoundException { -{L 7%j|R
int totalRecords = userDAO.getUserCount(); r8y,$Mv<)0
if(totalRecords == 0) 'h&>K,U?5
throw new ObjectNotFoundException f
4K)Z
e
} 5"Rj<
("userNotExist"); ]\ZJaU80I~
page = PageUtil.createPage(page, totalRecords); I7XM2xM
List users = userDAO.getUserByPage(page); Y]&2E/oc
returnnew Result(page, users); j5hQ;~Fa|
} IwXQbJ3v_
)q!dMZ(
} r^s$U,e#~
sWA-_ 4
jbOwpyH
V:D?i#%,z
,!AYeVq
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5#_GuL%
V+'zuX
询,接下来编写UserDAO的代码: !Y^B{bh
3. UserDAO 和 UserDAOImpl: bneP>Bd
java代码: L eUp!
q2Gm8>F1y.
IH=%%AS
/*Created on 2005-7-15*/ z5^Se!`5
package com.adt.dao; suX^"Io%!
[mUC7Kpi
import java.util.List; q 3,p=ijJ
l
Hu8ADva
import org.flyware.util.page.Page; +^,&z}(
Ak
}i;!p
Ue$
import net.sf.hibernate.HibernateException; !9zs>T&9a\
0}_1ZU
/** sZa>+
* @author Joa r_^]5C\
*/ 1- GtZ2
publicinterface UserDAO extends BaseDAO { $KRpu<5i}
YTe8C9eO
publicList getUserByName(String name)throws mk-L3H1@J3
w(%$~]h
HibernateException; 0a$hK9BH
ewYk>
publicint getUserCount()throws HibernateException; KmF+3g~#s
n?^X/R.22
publicList getUserByPage(Page page)throws vO;:~
"8[Vb#=*e
HibernateException; Ip,0C8T`Q
K]U8y$^
} f xD|_
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AIQ]lQ(
I}
]s(
qy!pD
R;
java代码: )Vy}oFT\
6:bvq?5a5
Ga"<qmLMc
/*Created on 2005-7-15*/ Zg;Ht
package com.adt.dao.impl; bu\D*-
Wf
*b"#
import java.util.List; wqn}t]
`t#Ie*
import org.flyware.util.page.Page; @aoHz8K
Q0_|?]v
import net.sf.hibernate.HibernateException; ;cZ]^kof
import net.sf.hibernate.Query; bJ.68643
ps]s
Tw
import com.adt.dao.UserDAO; J}&xS<
8+~|!)a
/** ZnB|vfL?
* @author Joa x6~`{N1N
M
*/ / ='/R7~
public class UserDAOImpl extends BaseDAOHibernateImpl z:tu_5w!,
k@C]~1
implements UserDAO { gl6 *bB=
Y4/ !b
/* (non-Javadoc) ?37Kc,o
* @see com.adt.dao.UserDAO#getUserByName r`=!4vY2
z9*7fT
(java.lang.String) NB/ wJ3 F
*/ P^bcc
publicList getUserByName(String name)throws }"9jCxXL
[hXU$Y>"0
HibernateException { /&'rQ`nd
String querySentence = "FROM user in class H!{Cr#=
L
sMS`o6
com.adt.po.User WHERE user.name=:name"; \5^GUT
Query query = getSession().createQuery iu.+bX|b
I'RhA\`
(querySentence); @Nt$B'+S&
query.setParameter("name", name); #%tN2cFDN
return query.list(); k*xgF[T
8
} ?IV3"\5
bQ2 '*T
/* (non-Javadoc) uYwJ[1C
* @see com.adt.dao.UserDAO#getUserCount() &mp@;wI6@
*/ 1=%\4\
publicint getUserCount()throws HibernateException { mH} 1Zy
int count = 0; A
ptzBs/
String querySentence = "SELECT count(*) FROM 6tmn1:
z+B"RV
user in class com.adt.po.User"; <P1sK/IZb
Query query = getSession().createQuery i;B)@op.#
+-OqO3R
(querySentence); .B9rG~
count = ((Integer)query.iterate().next wrW768WR
j"8|U
E
()).intValue(); t.oP]_mI
return count; p2~MJ
LK4
} w;Na9tR
2s@<k1EdPl
/* (non-Javadoc) 6<<ihm+
* @see com.adt.dao.UserDAO#getUserByPage JB= L\E}
A#j'JA>_
(org.flyware.util.page.Page) p1L8g[\
*/ Gvw:h9v
publicList getUserByPage(Page page)throws eu|cQ^>
Y/_b~Ahn
HibernateException { IGd]!
String querySentence = "FROM user in class _(s|@UT#
!'^gqaF+
com.adt.po.User"; >*%mJX/F
Query query = getSession().createQuery E5G=Kh[NP
\a8<DR\@O
(querySentence); Yl#r9TM
query.setFirstResult(page.getBeginIndex()) ;u0MY
.setMaxResults(page.getEveryPage()); $k|k 5cP8x
return query.list(); }l>0m
} LCRZ<?O[|
H`;q@
} 2!b+}+:
-HU5E>xG
P p[?E.]P
v(/T<^{cuk
Zi fAn
至此,一个完整的分页程序完成。前台的只需要调用 =FXZcP>h
@<O
Bt d
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ul@yXtj
+AyrKs?h
的综合体,而传入的参数page对象则可以由前台传入,如果用 257pO9]
fE;<)tU
webwork,甚至可以直接在配置文件中指定。 ?HBNd&gZ1G
0;j)rmt
下面给出一个webwork调用示例: ~P85Or
java代码: s1xl*lKX%
ch}t++`l]
Kuz
/
/*Created on 2005-6-17*/ "$*&bC#dE
package com.adt.action.user; B#_<?
Vs)Pg\B?
import java.util.List; dtw4cG
((}T^
import org.apache.commons.logging.Log; tN=B9bm3j
import org.apache.commons.logging.LogFactory; R(sPU>`MX
import org.flyware.util.page.Page; ?6F\cl0.
_>8ZL)NQQ
import com.adt.bo.Result; W4Ey]y"
import com.adt.service.UserService; wtCz%!OYB
import com.opensymphony.xwork.Action; P"LbWZ6Nj
%># VhK
/** %(IkUD
* @author Joa 9"3 7va
*/ K"O+`2$
publicclass ListUser implementsAction{ I65W^b4y
gUs.D_*
privatestaticfinal Log logger = LogFactory.getLog ao]Dm#HiO
.|Pq!uLvc
(ListUser.class); b Z0mK$B
j>(O1z7
private UserService userService; 0yhC_mI
N|OI~boV%
private Page page; |^^'GZ%a
_H9.AI
privateList users; \YE(E04w57
B 3Y,|*
/* K]{Y >w
* (non-Javadoc) yF-EHNNf
* WleE$ ,
* @see com.opensymphony.xwork.Action#execute() Nv@SpV'
*/ :nZVP_d+
publicString execute()throwsException{ )_eEM1
Result result = userService.listUser(page); a7+w)]r
page = result.getPage(); 7cTDbc!E-
users = result.getContent(); !=7(3<?
return SUCCESS; ]_6w(>A@3#
} gJE m
Em?Z
/** ' XJ>;",[
* @return Returns the page. SW!lSIk
*/ ToWiXH)4
public Page getPage(){ #)&kF+
return page; x{_:B
DY
} Ib(q9!L
b*w@kLLN
/** [ZC{eg+D
* @return Returns the users. \wR $_X&
*/ !2-f%x]tO
publicList getUsers(){ _?"P<3/iF
return users; 1 !N+hf
} .gL%0
z ;>xI~
/** I8R#EM%C#
* @param page i^SuVca
* The page to set. ;m<22@,E&
*/ d<{>&
publicvoid setPage(Page page){ {t<E*5N]a
this.page = page; ~:`5Y"Av:
} EDQKb TaPt
v?Z30?_&h
/** F xek#
* @param users |$*1!pL-QP
* The users to set. or~2r8
*/ LhN?j5XqM
publicvoid setUsers(List users){ #|<\q* <
this.users = users; ME.l{?v
} kj_MzgC'?
.dA_}
/** @d&(*9Y
* @param userService s!WGs_1@
* The userService to set. _ebo
*/ 0, b.;r
publicvoid setUserService(UserService userService){ e"7<&%
Oq
this.userService = userService; T_\Nvzb}
} ;gS)o#v0
} Y fRjr
Gw!VPFV>W
sIUhk7Cd8
=35g:fL
<v&L90+s\;
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, HQtR;[1
52X[{
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
BK$cN>J
k }amSsE
么只需要: f4%Z~3P
java代码: Z^tTR]u\$
>A5*=@7bY?
0R2KI,WI
<?xml version="1.0"?> WC&V9Yk
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +2:\oy}!8
'e&L53n
1.0//EN" "http://www.opensymphony.com/xwork/xwork- p.wed%O.
@c;XwU]2t
1.0.dtd"> 0m2%ucKw
m*bTELb
<xwork> |7Dc7p"D
QZwUv<*
<package name="user" extends="webwork- rra|}l4Y
4S%s=vw
interceptors"> E?v9c>c
,>
Ya%;h2k
<!-- The default interceptor stack name [3K& cX}B
pc/x&VY%
--> \#50;
8VJ
<default-interceptor-ref xG_LEk( zD
u[:-^H
name="myDefaultWebStack"/> ke2zxX2f
U/}("i![Dy
<action name="listUser" V ,+&.A23
ttP|}|O
class="com.adt.action.user.ListUser"> ~ 3!yd0[k
<param hs;YMUA"
:)9CG!2y<M
name="page.everyPage">10</param> Ew<
sK9[o
<result 'c7'iDM
<z.Y#{p?k
name="success">/user/user_list.jsp</result> $^TxLv
</action> g5&ZXA
p>ba6BDJT
</package> 4h*c{do
'hGUsi
</xwork> oV/:T\Qn=
H*.v*ro9_
K#%@4]jO3
=I.uf
=67ab_V
&0*7]Wo*
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 5'<J@3B
I]@QhCm0
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。 p=XEMVqm
(X?HuWTm
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !We9T )e
*w#^`yeo
QbJE+m5
}j)][{i*x
zQxTPd
我写的一个用于分页的类,用了泛型了,hoho E8/Pi>QW
uv|RpIv e:
java代码: sB@9L L]&|
Nf5zQ@o_y
i}L*PCP
package com.intokr.util; $x/VO\Z{-
A3Xfu$[u
import java.util.List; <B
Vx%
l5T0x=y9!
/** n-he|u
* 用于分页的类<br> t5aX9WIW
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pP-L{bT
* NwcRH9};i
* @version 0.01 &W8fEQwa
* @author cheng ,Mr_F^|
*/ <YM!K8hu$
public class Paginator<E> { P<CPA7K
privateint count = 0; // 总记录数 2RU/oqmR
privateint p = 1; // 页编号 ~v@.YJoZ4Z
privateint num = 20; // 每页的记录数 wzj:PS
privateList<E> results = null; // 结果 :u,Ji9
u
FrsXLUY
/** &c^tJ-s
* 结果总数 \zJb}NbnT
*/ ms&6N']
publicint getCount(){ XI'.L ~
return count; tXCgRU
} HGao} @'
/[qLf:rGI
publicvoid setCount(int count){ #e[S+a
this.count = count; 2Rqpok4
} Ofc
u4pi
/pC60y}O0
/** :-Wh'H(
* 本结果所在的页码,从1开始 HPY;UN
* [Mk:Zz%
* @return Returns the pageNo. j.yh>"de
*/
/s~BE ,su
publicint getP(){ 6/.kL;AI
return p; Z817f]l
} sis1Dh9:
c;,-I
/** b{CS1P
* if(p<=0) p=1 (sW$2a
* mKLWz1GZ
* @param p cte
Wl/v
*/ % kaV?j
publicvoid setP(int p){ M_O) w^
'
if(p <= 0) ~#dfZa&
p = 1; *EPJeblAV
this.p = p; $3S`A]xO
} 9T\\hM)k
!S'!oinV
/** 8{
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* 每页记录数量 z:8ieJ)C
*/ o?d`o$
publicint getNum(){ L@S1C=-/
return num; R].xT-1
} @dn&M9Z
BS2'BS8
/** tmQ,>
* if(num<1) num=1 b%h.>ij?
*/ t9.| i H
publicvoid setNum(int num){ (+nnX7V?I
if(num < 1) w5vzj%6i
num = 1; DH"_.j
this.num = num; q>6RO2,
} GF36G?iEi
5,BvT>zFY
/** y[/:?O}g4
* 获得总页数 <OrQbrWQa
*/ h%5keiA
publicint getPageNum(){ 5S ) N&%
return(count - 1) / num + 1; zCS&