Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 B|XrjI?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 jkTC/9AE|
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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 yK9:LXhf
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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 }@6ws/5
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分页支持类: q(xr5iuP_
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java代码: n .is+2t
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package com.javaeye.common.util; ~;$,h ET
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import java.util.List; rMr:\M]t
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publicclass PaginationSupport { ;&7dX^oH
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publicfinalstaticint PAGESIZE = 30; bji5X')~#
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privateint pageSize = PAGESIZE; ,^wjtA3j8
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privateList items; <OgwA$abl%
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privateint totalCount; JX!z,X?r4
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privateint[] indexes = newint[0]; 1?I_fA}
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privateint startIndex = 0; R|D%1@i]
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public PaginationSupport(List items, int (:er~Y}
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totalCount){ gug9cmA/Q7
setPageSize(PAGESIZE); _ \&vA5-
setTotalCount(totalCount); Mbm'cM&}
setItems(items); 'k'"+
setStartIndex(0); t?Ku6Z'
} Dxvizd>VU
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public PaginationSupport(List items, int (}B3df
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totalCount, int startIndex){ >G9YYt~
setPageSize(PAGESIZE); *RYok{w
setTotalCount(totalCount); L0\~K~q
setItems(items); xqSoE[<v
setStartIndex(startIndex); ,F%2'W
} R<djW5 ()f
i 1dE.f;
public PaginationSupport(List items, int M:M"7>:
&c[ISc>N{
totalCount, int pageSize, int startIndex){ +h]~m_O
setPageSize(pageSize); PPAcEXsIu
setTotalCount(totalCount); Kj53"eW
setItems(items); w`YN#G
setStartIndex(startIndex); h-.xx4D
}
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publicList getItems(){ eQqnPqi-
return items; v`r![QpYf
} !P8Y(i
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publicvoid setItems(List items){ E]O/'-
this.items = items; t7-6A
} I3qTSX-
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publicint getPageSize(){ $sxRRem{?
return pageSize; 9 1.gE*D
} &M>o
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publicvoid setPageSize(int pageSize){ [CG3&J
this.pageSize = pageSize; b^:frjaE3
} #fx>{ vzH
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publicint getTotalCount(){ &K*Kr=9N
return totalCount; \/s0p
} NR3h|'eC
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publicvoid setTotalCount(int totalCount){ 9ls*L!Jw
if(totalCount > 0){ J
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this.totalCount = totalCount; tdsfCvF=a
int count = totalCount / "IHFme@^
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pageSize; y[{}124
if(totalCount % pageSize > 0) 3ytlD '
count++; Na>w~
indexes = newint[count]; !aB~G}'
for(int i = 0; i < count; i++){ O70#lvsM;
indexes = pageSize * ;I9g;}
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} WES$B7y
}else{ kBU`Q{.
this.totalCount = 0; S2jn pf}
} )7C+hQe
} W m&*
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publicint[] getIndexes(){ ]f~!Qk!I7r
return indexes; >fi_:o
} )g?ox{Hol
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publicvoid setIndexes(int[] indexes){ 704_ehrlE
this.indexes = indexes; :b0|v`FU
} [sNvCE$\]
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publicint getStartIndex(){ *C);IdhK%y
return startIndex; Tb:6IC7="
} Pcjrv:0$
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publicvoid setStartIndex(int startIndex){ X[!S7[d-y
if(totalCount <= 0) sd9b9?qiu
this.startIndex = 0; "$/1.SX;]
elseif(startIndex >= totalCount) 8VtRRtl
this.startIndex = indexes |>RNIJ]
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[indexes.length - 1]; ||L^yI~_d
elseif(startIndex < 0) T/FZn{I
this.startIndex = 0; ce[
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else{ |xF!3GGms
this.startIndex = indexes Gs\D`|3=
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[startIndex / pageSize]; y=0)vi{]
} GExr] 2r
} kl1/(
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publicint getNextIndex(){ }eF
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int nextIndex = getStartIndex() + g[*"LOw
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pageSize; S17;;w0
if(nextIndex >= totalCount) \ Q^grX
return getStartIndex(); 0(>3L :
else ^/VnRpU
return nextIndex; {+]tx46$
} "@^Q"RF
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publicint getPreviousIndex(){ SOZs!9oi
int previousIndex = getStartIndex() - )PkW,214#
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pageSize; )FSEHQ
if(previousIndex < 0)
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return0; +|x{?%.O
else G`;\"9t5h
return previousIndex; z%1e>`\E
} c39j|/!;Y
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} Y/5(BK)
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抽象业务类
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java代码: i&8|@CACb
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/** D2GF4%|
* Created on 2005-7-12 } '?qUy3x
*/ _%er,Ed
package com.javaeye.common.business; S dN&%(ZE
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import java.io.Serializable; 6Xz d>5x
import java.util.List; 61b*uoq0w?
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import org.hibernate.Criteria; MsBm0r`a
import org.hibernate.HibernateException; IMncl=1
import org.hibernate.Session; ;l1.jQh
import org.hibernate.criterion.DetachedCriteria; B;S'l|-?
import org.hibernate.criterion.Projections; #
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import rW090Py
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org.springframework.orm.hibernate3.HibernateCallback; [2YPV\=
import 8;L;R~Q
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org.springframework.orm.hibernate3.support.HibernateDaoS &CcW(-
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upport; {bADMj1
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import com.javaeye.common.util.PaginationSupport; SQhVdYU1'
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public abstract class AbstractManager extends {6WG
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HibernateDaoSupport { OR*JWW[]
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privateboolean cacheQueries = false; t|V<K^
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privateString queryCacheRegion; )0/*j]Kf
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publicvoid setCacheQueries(boolean AorY#oq
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cacheQueries){ -EE'xh-zD
this.cacheQueries = cacheQueries; `U b*rOMu
}
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publicvoid setQueryCacheRegion(String i39ZBs@
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queryCacheRegion){ /t<
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this.queryCacheRegion = 2Wu`Dp;&l
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queryCacheRegion; Vfga%K%l F
} y631;dU
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publicvoid save(finalObject entity){ %8D>aS U
getHibernateTemplate().save(entity); g1|Pyt{
} t0jE\6r
XI ;] c5
publicvoid persist(finalObject entity){ t$%<eF@w
getHibernateTemplate().save(entity); }^0'IAXi
} FwlDP
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publicvoid update(finalObject entity){ |!9xL*A
getHibernateTemplate().update(entity); AT+l%%
} &6C]|13;
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publicvoid delete(finalObject entity){ l^}u S|c(
getHibernateTemplate().delete(entity); )c&ya|h
} 38T]qz[Sn
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publicObject load(finalClass entity,
;}?ZH4.S
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finalSerializable id){ W^h,O+vk
return getHibernateTemplate().load fv#ov+B
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(entity, id); xGQP*nZ
} qR!ZtJ5j
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publicObject get(finalClass entity, b@&uwS v
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finalSerializable id){ }~|`h1JF
return getHibernateTemplate().get _S7?c^:~
@2L^?*n=
(entity, id); G![d_F"e
} 4K'U}W
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publicList findAll(finalClass entity){ T0")Ryu
return getHibernateTemplate().find("from @wa"pWx8
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" + entity.getName()); wW p7N
} W{.:Cf9
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publicList findByNamedQuery(finalString zN!yOlp5
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namedQuery){ HZ%V>88
return getHibernateTemplate wkGr}
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().findByNamedQuery(namedQuery); i8k} B
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} fMFkA(Of^
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publicList findByNamedQuery(finalString query, yQUrHxm
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finalObject parameter){ +B " aUF
return getHibernateTemplate Be]z @E1x
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().findByNamedQuery(query, parameter); oNe:<YT
} iB(?}SaAZ
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publicList findByNamedQuery(finalString query, lAM)X&}0
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finalObject[] parameters){ H[p~1%Lq
return getHibernateTemplate Ar~/KRK
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().findByNamedQuery(query, parameters); |(*btdqy3
} I+;e#v,%U
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publicList find(finalString query){ hWbu
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return getHibernateTemplate().find { 22ey`@`h
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(query); .<>t2,Af
} 1aO(+](;
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publicList find(finalString query, finalObject *Vq'%b9
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parameter){ l<uI-RX"
return getHibernateTemplate().find Uz,P^\8^$
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(query, parameter); 4cSs=|m?+
} ! PGCoI
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public PaginationSupport findPageByCriteria qjkWCLOd
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(final DetachedCriteria detachedCriteria){ 5]]QW3
return findPageByCriteria 4y+hr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); O4f9n
} Lf^
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public PaginationSupport findPageByCriteria Z{B [r;
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(final DetachedCriteria detachedCriteria, finalint "?6*W"N9
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startIndex){ 9NVtvBA
return findPageByCriteria \G v\&_
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(detachedCriteria, PaginationSupport.PAGESIZE, faLfdUimJ
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startIndex); O}cfb4"
} _){u5%vv
cwaR#-#
public PaginationSupport findPageByCriteria 2i!R>`
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(final DetachedCriteria detachedCriteria, finalint ^Ff fc@=
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pageSize, W%ix|R^2]
finalint startIndex){ M<Z#4Gg#4
return(PaginationSupport) gM1:*YK
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getHibernateTemplate().execute(new HibernateCallback(){ CpN*1s})d
publicObject doInHibernate XU}i<5
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(Session session)throws HibernateException {
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Criteria criteria = bupW*fD:
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detachedCriteria.getExecutableCriteria(session); 8cY5:plK
int totalCount = K[noW
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((Integer) criteria.setProjection(Projections.rowCount Lp$&eROFVs
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()).uniqueResult()).intValue(); <LBCu;
criteria.setProjection 5ip ZdQ^
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(null); 7]L}~
List items = NPBOG1q%
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criteria.setFirstResult(startIndex).setMaxResults SP2";,%/9
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(pageSize).list(); 6tVp%@
PaginationSupport ps = e
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new PaginationSupport(items, totalCount, pageSize, 0[ n;ZL~
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startIndex); p|;#frj
return ps; E?K(MT&@
} ,82?kky
}, true); 2-g 5Gb2|
} d<\X)-"
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public List findAllByCriteria(final 'SG<F,[3
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DetachedCriteria detachedCriteria){ fH,h\0
return(List) getHibernateTemplate PR7bu%Y*eD
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().execute(new HibernateCallback(){ @&G
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publicObject doInHibernate bsc b
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(Session session)throws HibernateException { Vz,"vBds
Criteria criteria = pDr/8HEh
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detachedCriteria.getExecutableCriteria(session); J{uqbrJICr
return criteria.list(); fEK%)Z:0
} =1B;<aZH!
}, true); v%c--cO(S4
} :Z;kMrU
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public int getCountByCriteria(final p_g8d&]V
P)=$0kR3
DetachedCriteria detachedCriteria){ B$97"$#u
Integer count = (Integer) !qs~j=;y3
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getHibernateTemplate().execute(new HibernateCallback(){ G
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publicObject doInHibernate r`0oI66B/
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(Session session)throws HibernateException { 14-uy.0[
Criteria criteria = @DR?^
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detachedCriteria.getExecutableCriteria(session); Q?m= a0g
return rJd-e96
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criteria.setProjection(Projections.rowCount ~|wh/]{b9
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()).uniqueResult(); ''EFh&F
} J]*?_>"#8
}, true); ;2eZa|M*q
return count.intValue(); `@ Ont+
} ss7Z-A 4z
} Kzfy0LWM
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用户在web层构造查询条件detachedCriteria,和可选的 ~ln96*)M;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 x5W@zqj
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PaginationSupport的实例ps。 r<kqs,-~
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ps.getItems()得到已分页好的结果集 \9.@Tg8`
ps.getIndexes()得到分页索引的数组 _vE[TFy
ps.getTotalCount()得到总结果数 ~{yQsEU
ps.getStartIndex()当前分页索引 "g;}B"rG
ps.getNextIndex()下一页索引 K&vqk/JW1
ps.getPreviousIndex()上一页索引 V@ph.)z
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ZEU/6.
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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 |f&=9%
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一下代码重构了。 `OyYo^+D|.
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我把原本我的做法也提供出来供大家讨论吧: Q(YQ$i"S
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首先,为了实现分页查询,我封装了一个Page类: DKf:0E8
java代码: O>L
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/*Created on 2005-4-14*/ +D+Rf,D
package org.flyware.util.page; :E9 @9>3S
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/** Z0%Qy+%
* @author Joa 7(= 09z
* L[:b\O/p,
*/ 3/((7O[
publicclass Page { < G:G/
ob.=QQQs
/** imply if the page has previous page */ w!^{Q'/,Q
privateboolean hasPrePage; -r"h[UV)
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/** imply if the page has next page */ 5PCKBevV
privateboolean hasNextPage; +q3E>K9a
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/** the number of every page */ `~3y[j]kO
privateint everyPage; rwou[QU
sv?Lk4_
/** the total page number */ js\|xfDxP
privateint totalPage; |nj,]pA
wi/dR}*A
/** the number of current page */ |d8x55dk
privateint currentPage; :s OsG&y
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/** the begin index of the records by the current [P23.`G~J
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query */ H-.8{8
privateint beginIndex; 4#y
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/** The default constructor */ <jvSV5%
public Page(){ P 6|\
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p
} =m?x|Zc_v
!,< )y}L^)
/** construct the page by everyPage ?5g0#wqI
* @param everyPage Jk!*j
* */ 2aUy1*aM
public Page(int everyPage){ YAf`Fnmw
this.everyPage = everyPage; x7]Yn'^'
} &*#- %<=1
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/** The whole constructor */ sC.aT(meJ
public Page(boolean hasPrePage, boolean hasNextPage, ,s,VOyr @F
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int everyPage, int totalPage, |H'4];>R?
int currentPage, int beginIndex){ )tyhf(p6
this.hasPrePage = hasPrePage; wd`lN,WiW
this.hasNextPage = hasNextPage; !4f0VQI
this.everyPage = everyPage; l4sFT)}-J
this.totalPage = totalPage; do1aH$Iw
this.currentPage = currentPage; 2=6}! Y
this.beginIndex = beginIndex; IA XoEBlMs
} 80M"`6
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/** *h>KeIB;
* @return ]D;X"2I2'b
* Returns the beginIndex. ED={OZD8
*/ C&vUZa[p
publicint getBeginIndex(){ MZX-<p+
return beginIndex; }G#TYF}
} 3i'L5f67
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/** 26,!HmtC
* @param beginIndex CcZ\QOet&C
* The beginIndex to set. lklMdsIdj
*/ M8BN'%S
publicvoid setBeginIndex(int beginIndex){ +JMB98+l
this.beginIndex = beginIndex; iwl\&uNQU
} [y}0X^9,E
]HK|xO(
/** zMkjdjb
* @return xmEmdOoD
* Returns the currentPage. F`$V H^%V
*/ KU> $=Rd
publicint getCurrentPage(){ <"g ^V
return currentPage; ;oQ*gd
} <d GGH
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/** L)cy&"L|
* @param currentPage pUs s_3
* The currentPage to set. xi.L?"^/!
*/ pk*cch#
publicvoid setCurrentPage(int currentPage){ R)3P"sGuN
this.currentPage = currentPage; rVx%"_'*-
} #mNM5(o
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/** =W6AUN/%p
* @return RY(\/W#$
* Returns the everyPage. MHv2r
*/ tf?u ;n
publicint getEveryPage(){ \)=X=yn2
return everyPage; yk4Huq&2
} q#$4Kt;
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/** ^;b$`*M1
* @param everyPage YI=03}I
* The everyPage to set. <(YmkOS+
*/ xbFoXYqgP
publicvoid setEveryPage(int everyPage){ J1^6p*]GX
this.everyPage = everyPage; R)AFaP |
} Ub%al
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/** Rl7V~dUY
* @return +)#d+@-
* Returns the hasNextPage. P~V0<$C
*/ q^
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publicboolean getHasNextPage(){ >g]S"ku|
return hasNextPage; aN7VGc
} ZE@!s3\
30(O]@f~
/** %C_RBd
* @param hasNextPage 6OJ`R.DM`
* The hasNextPage to set. $z!o&3c'x
*/ )p&FDK#ob=
publicvoid setHasNextPage(boolean hasNextPage){ ;O*y$|+PA
this.hasNextPage = hasNextPage; NJG-~w
} e~C^*w L
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/** !\Y85o>JU
* @return w`(EW>i
* Returns the hasPrePage. FnN@W^/z
*/ 5eI3a!E]O
publicboolean getHasPrePage(){ e7f3dqn0
return hasPrePage; E?o1&(2p
} 28u)q2s^W|
N4$!V}pp
/** }[P1Va[!
* @param hasPrePage Ux~rBv''
* The hasPrePage to set. f?wn;;z`
*/ _L mDF8Q(
publicvoid setHasPrePage(boolean hasPrePage){ X6jW mo8]
this.hasPrePage = hasPrePage; .]+oE$,!
} Y%v?ROql
@|:_ ?
/** )_P|_(
* @return Returns the totalPage. sgdxr!1?y
* uV r6tb1
*/ .0l0*~[
publicint getTotalPage(){ ^u zJu(
return totalPage; 4^T@n$2N
} S) /(~
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/** acgtXfHR
* @param totalPage Y27x;U
* The totalPage to set. {AbQaw
*/ @EZ@X/8{&
publicvoid setTotalPage(int totalPage){ 5Z]zul@+*
this.totalPage = totalPage; :- B,Q3d
} zY\pZG
1ID0'j$
} o}&TFhT
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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 i1]*5;q
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个PageUtil,负责对Page对象进行构造: } 5~|h%
java代码: D"^4X'6
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/*Created on 2005-4-14*/ 9ALE6
package org.flyware.util.page; R[Q`2ggG
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import org.apache.commons.logging.Log; 413,O~^
import org.apache.commons.logging.LogFactory; 1!,xB]v1Ri
3.M<ATe^
/** :<ye:P1s
* @author Joa %|L+~ =
* m6J7)Wp
*/ 7%C6hEP/*W
publicclass PageUtil { <aJdm!6
T4,dhS|
privatestaticfinal Log logger = LogFactory.getLog 0 1U/{D6D
}eUeADbC
(PageUtil.class); \}SA{)
8)IpQG
/** )N`a4p
* Use the origin page to create a new page uK6`3lCD
* @param page xc[LbaBG
* @param totalRecords lub(chCE[
* @return _5'OQ'P2
*/ g4,>cqRkq
publicstatic Page createPage(Page page, int ?N2/;u>
%~ uMa
totalRecords){ U4]>8L
return createPage(page.getEveryPage(), + yX\!H"
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page.getCurrentPage(), totalRecords); 9%e&Z'l
} QAYhAOS|e
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/** LaL.C^K
* the basic page utils not including exception o7"2"(
=>
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handler DC4,*a~
* @param everyPage ?4%'6R
* @param currentPage t_HS0rxG
* @param totalRecords .#zmX\a
* @return page .v<c_~y
*/ asT:/z0
publicstatic Page createPage(int everyPage, int _"
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currentPage, int totalRecords){ &{${ Fq
everyPage = getEveryPage(everyPage); <fq?{z
currentPage = getCurrentPage(currentPage); MW|Qop[
int beginIndex = getBeginIndex(everyPage, NZ:A?h2JR
xQV5-VoFC
currentPage); 40cgsRa|
int totalPage = getTotalPage(everyPage, Ei!5Qya>
dn0?#=
totalRecords); ]m}<0-0
boolean hasNextPage = hasNextPage(currentPage, jj^{^,z\
j+0=)Q%I=
totalPage); dIiQ^M
boolean hasPrePage = hasPrePage(currentPage); pp{Za@j
jQjtO"\JG
returnnew Page(hasPrePage, hasNextPage, rW$ )f
everyPage, totalPage, E-,/@4k
currentPage, EU?)AxH^
1<#J[$V
beginIndex); #~J)?JL
} 4:\1S~WW
5 _X|U*+5
privatestaticint getEveryPage(int everyPage){ {=Y%=^! s
return everyPage == 0 ? 10 : everyPage; d<mj=V@bd
} Bbuy
y
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privatestaticint getCurrentPage(int currentPage){ w'[lIEP 2$
return currentPage == 0 ? 1 : currentPage; ]$ [J_f*x
} ax{+7 k
;O=tSEe
privatestaticint getBeginIndex(int everyPage, int p9]008C89
%Od?(m"&
currentPage){ )G$/II9d
return(currentPage - 1) * everyPage; IV$pA`|V
} s)Bl1\Q
ycAQHY~n
privatestaticint getTotalPage(int everyPage, int ]jNv}{
M&P?/Zi=L
totalRecords){ 4$Oakl*l
int totalPage = 0; m89-rR:Kc
P/;sZo
if(totalRecords % everyPage == 0) :wiQ^ea
totalPage = totalRecords / everyPage; zbsdK
else 7{HJjH!zx
totalPage = totalRecords / everyPage + 1 ; y.6D Z
vto^[a6?
return totalPage; SP][xdN7
} g:0-`,[
(`+%K_
privatestaticboolean hasPrePage(int currentPage){ II$B"-
return currentPage == 1 ? false : true; {@K>oaZ
} _l$V|
39| W(,
privatestaticboolean hasNextPage(int currentPage, ,!U._ic'B
ZdbZ^DUR<(
int totalPage){ ^`ah\L
return currentPage == totalPage || totalPage == : vN'eL|#
o*OYZ/_L
0 ? false : true; e|x1Dq
}
pv<$
o
wc7gOrPpm
7J@iJW],,
} g?,\bmH E
7b7~D +b
J})G l
f7B)iI!
]A oRK=aH
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。 v'`VyXetl
)cnH %6X
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 e>`+Vk^Jc
`I|$U)'
做法如下: (V2~txMh
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 K=|x"6\
e1$T%?(&[
的信息,和一个结果集List: GSzb
java代码: 7:7i}`O
bup)cX^
\"!Fw)wj
/*Created on 2005-6-13*/ vmW >$P
package com.adt.bo; yVQ0;h
IC&>PwXb
import java.util.List; ? <b>2j
l-` M
9#
import org.flyware.util.page.Page; 'Rbv3U
13
`Or(>U
/** AlP}H~|M7
* @author Joa sPMCN's
*/ ;hP43Bi
publicclass Result { zu8
Zpfsh2`
private Page page; b1An2e[
'qR)f\em
private List content; VJW%y)_[
ug]WIG7 S
/** ]%AmX-U
* The default constructor A")F7F31c
*/ t[HfaW1W
public Result(){ fBtTJ+51}
super(); Z$qLY<aV
} xUT]6T0dB
hSQ*_#
/** a<%Ivqni
* The constructor using fields X@l>mAk
* 9H^$cM9C
* @param page a2J01B
* @param content 3>60_:+Zb
*/ D#VUx9kugv
public Result(Page page, List content){ u.!}s2wT#
this.page = page; X2CpA;#;7l
this.content = content; }>`rf{T
} |~)!8N.{
WI@l2`X
/** {D6lSj
* @return Returns the content. ]w7wwU^^*U
*/ R@ksYC3 F
publicList getContent(){ nPlg5&E
return content; 05o +VF;z
} ^FO&GM2a
f]c{,LFvZ
/** TsiI5'tx
* @return Returns the page. BO5\rRa0
*/ +5AWX,9,-
public Page getPage(){ IIj
:\?r
return page; 6"@`iY
} jL^3/0"o
GYp}V0
/** "d1~(0=6<m
* @param content Cp!bsasj
* The content to set. jU~q~e7Te
*/ ,O`a_b]
public void setContent(List content){ KK-}&N8
this.content = content; VsIDd}~C%
} Y52f8qQq
d@d\9*mn
/** 4MM /i}
* @param page z89!\Q
* The page to set. pNt,RRoR
*/ zDakl*
publicvoid setPage(Page page){ =Oyn<
this.page = page; "pRi1Y5)l
} !>E$2}Q|]
} tfz"9PV80
mz-sazgV
f2*e&+LjTP
WdtZ{H
Y6+/_$N4|
2. 编写业务逻辑接口,并实现它(UserManager, (FVHtZi7
&/+LY_r'<I
UserManagerImpl) h*X5Oh6
java代码: fYxdG|>{u
BIQQJLu
+f){x9
:
/*Created on 2005-7-15*/ zCz"[9k
package com.adt.service; HpCTQ\H
W!Qaa(o?
import net.sf.hibernate.HibernateException; h^ o@=%b
5rX_85 ]
import org.flyware.util.page.Page; L!| `IK
8'<RPU}M
import com.adt.bo.Result; g#*LJ`1
4:Ton
/** (T65pP_P 7
* @author Joa ]a=n(`l?
*/ lGhhH_
publicinterface UserManager { = Z
/*
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public Result listUser(Page page)throws E'g?44vyw
.DrGr:UW
HibernateException; >;s!X(6b
u{J\X$]
} lZ'ZL*
Xd 5 vNmQn
'QOV! D
rbw~Ml0
y8.3tp
java代码: k-jlYHsA
9z'(4U
*8% nbR
/*Created on 2005-7-15*/ ^1w<wB\B
package com.adt.service.impl; ']C" 'b
"wi}/,)
import java.util.List; prw% )#,
`ElJL{Rn
import net.sf.hibernate.HibernateException; ,DIr&5>p2
'hNRIM1
import org.flyware.util.page.Page; V*,6_-^l
import org.flyware.util.page.PageUtil; nN'>>'@>
p3Z[-2I
import com.adt.bo.Result; K3;~|U-l
import com.adt.dao.UserDAO; #&sw%CD
import com.adt.exception.ObjectNotFoundException; =Sjf-o1V
import com.adt.service.UserManager; -/ YY.F-
N"[r_!
/** MwE^.6xl{
* @author Joa v;.w*x8Jw
*/ ?QRoSQ6
publicclass UserManagerImpl implements UserManager { q,>-4Cm
@v~<E?Un
private UserDAO userDAO; w,zm$s ^
BbG=vy8'l
/** o>^@s4t
* @param userDAO The userDAO to set. 1$n!Lj=5
*/
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publicvoid setUserDAO(UserDAO userDAO){ ~P,@">}
this.userDAO = userDAO; 3gQ2wP*K
} #,S0uA
ALi3JU
/* (non-Javadoc) Iy;bzHXs
* @see com.adt.service.UserManager#listUser |'QgL0?
DR<=C`<4(
(org.flyware.util.page.Page) Hd ${I",
*/ 4<btWbk5u*
public Result listUser(Page page)throws tGwQUn
OI)U c .
HibernateException, ObjectNotFoundException { h[& \OD,P
int totalRecords = userDAO.getUserCount(); cnL@j_mb
if(totalRecords == 0) g0M/Sv
throw new ObjectNotFoundException V8947h|&
i Qa=4'9;
("userNotExist"); ;mauA#vd
page = PageUtil.createPage(page, totalRecords); c:u2a/Q?
List users = userDAO.getUserByPage(page); y{9<>28
returnnew Result(page, users); [pzo[0G 'v
} \=
G8
8,&pX ga
} 1$v1:6
7hAc6M$h;
Gj- *D7X5
MT^krv(G
AiUK#I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Y;1J`oT
55V&[>|K5
询,接下来编写UserDAO的代码: K*aGz8N
3. UserDAO 和 UserDAOImpl: umI6# Vd`=
java代码: 4mci@1K#^
U&OE*dq
`{+aJ0<S
/*Created on 2005-7-15*/ >U62vX"
package com.adt.dao; qlg?'l$03)
I,7n-G_'
import java.util.List; FQBAt0
~+&Z4CYb
import org.flyware.util.page.Page; n_S)9C'=
pP*`b<|
import net.sf.hibernate.HibernateException; %0lJ(hm
yL"pzD`[H
/** 9V?:!%J
* @author Joa ,K8(D<{
*/ =P`l+k3
publicinterface UserDAO extends BaseDAO { =`f"8,5
WoDQg64
publicList getUserByName(String name)throws KFf6um
3.V-r59
HibernateException; ^cI 0d,3=
Y/`*t(/5
publicint getUserCount()throws HibernateException; B'-L-]\H
9~6~[z
publicList getUserByPage(Page page)throws i3<ZFR
m:C |R-IL
HibernateException; ^ jT1q_0
GU]_Z!3
} !A#(bC
ct@i]}"`
,_U3p ,
A>Xt 5vk+
o(3`-ucD`
java代码: `cpUl*Y=
95^-ptO{1`
(a@}J.lL
/*Created on 2005-7-15*/ #2Z\K>L
package com.adt.dao.impl; (6~~e$j
$|H7fn(r
import java.util.List; `dm}|$X|
$?dutbE
import org.flyware.util.page.Page; KO&oT#S
{PQ!o^7y
import net.sf.hibernate.HibernateException; DS>qth
import net.sf.hibernate.Query; XFrgnnt
M|\C@,F]8
import com.adt.dao.UserDAO; |s{[<;
=(]||1.
/** %z5P%F'5
* @author Joa Jsw%.<
*/ Bw*6X`'Q
public class UserDAOImpl extends BaseDAOHibernateImpl /]hE?cmj
l ArDOFl]x
implements UserDAO { YY9Ub
x
L]Z3"p%
/* (non-Javadoc) I;3Uzv
* @see com.adt.dao.UserDAO#getUserByName [LrA_N
&&sCaNb
(java.lang.String) XZ1WY(
*/ JB(P-Y#yyA
publicList getUserByName(String name)throws WG(%Pkowv
u{(-`Al}L
HibernateException { "bk'#?9
String querySentence = "FROM user in class VQ'DNv| 9
h$I
2T
com.adt.po.User WHERE user.name=:name"; TI^M9;b
Query query = getSession().createQuery jjU("b=
NiO|Aki{
(querySentence); ^laf!kIP
query.setParameter("name", name); 4KT-U6zNx
return query.list(); UWW_[dJr
} %N0cp@Vz
0Lki(
/* (non-Javadoc) F<|x_6a\
* @see com.adt.dao.UserDAO#getUserCount() 'qnnZE
*/ -40OS=wpA
publicint getUserCount()throws HibernateException { 8[mj*^P
int count = 0; z! /
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String querySentence = "SELECT count(*) FROM h;Se.{
@Sd l~'"
user in class com.adt.po.User"; 5Q.z#]Lg
Query query = getSession().createQuery ,`;Dre
O*y@4AR"S
(querySentence); BZ-)XF'4
count = ((Integer)query.iterate().next [SA$d`B/
=VM4Q+'K
()).intValue(); iJem9XXb
return count; ;'xd8Jf
} =EdLffU[J
v
%GcNjZk5
/* (non-Javadoc) /8tF7Mmr
* @see com.adt.dao.UserDAO#getUserByPage A3c&VT6Q
;,Q6AS!
(org.flyware.util.page.Page) (N` x
*/ d@0&
publicList getUserByPage(Page page)throws *m9,_~t
[sweN]b6F
HibernateException { n;,>Fv
String querySentence = "FROM user in class s2M|ni=
R8YA"(j!L
com.adt.po.User"; h!UB#-
Query query = getSession().createQuery /ng+IC3
u=9)A9
(querySentence); a<ztA:xt|1
query.setFirstResult(page.getBeginIndex()) +\@WOs
.setMaxResults(page.getEveryPage()); ;yVT:qd
%
return query.list(); O]N
8QH
} ~Y /55uC
1E|~;wo\
} f]JLFg7
!
fSM6Vo
Bq) aA)gF
d:1TSJff%/
OJ Y_u[
至此,一个完整的分页程序完成。前台的只需要调用 2Ed
xBW{Wyh
userManager.listUser(page)即可得到一个Page对象和结果集对象 6pi^ rpo
x0 dO^D
的综合体,而传入的参数page对象则可以由前台传入,如果用 v9K{oB
~[d |:]
webwork,甚至可以直接在配置文件中指定。 m_n*_tX
yk7 l{F
下面给出一个webwork调用示例: 'AjDB:Mt$
java代码: UM QsYD)
56Gc[<nR
{^qp~0
/*Created on 2005-6-17*/ __N#Y/e ]
package com.adt.action.user; 5\|u]
~b
M4m90C;dq
import java.util.List; I:9jn"
,}hJ)
import org.apache.commons.logging.Log; nax(V
import org.apache.commons.logging.LogFactory; &T)h9fyc
import org.flyware.util.page.Page; G,6Zy-Y9
O.g!k"nas&
import com.adt.bo.Result; -F+dmI,1$
import com.adt.service.UserService; Jf|6 FQo&
import com.opensymphony.xwork.Action; eX9Hwq4X44
eaGd:(
/** 5$C]$o}
* @author Joa ddiBjp2.!
*/ 07:N)y,
publicclass ListUser implementsAction{ A]k-bX= s
IU*w'a
privatestaticfinal Log logger = LogFactory.getLog ~0ku,P#D
;`P}\Q{
(ListUser.class); $7bl,~Z
TaN]{k
private UserService userService; js#72T/_n
L&s|<<L
private Page page; rS3* k3
6s$jt-bH
privateList users; 3]u[NR
<h7FS90S
/* &lp5W)D
* (non-Javadoc) s wIJmA
* 0~0OQ/>7
* @see com.opensymphony.xwork.Action#execute() Ws>2S
*/ fqcFfz6?x
publicString execute()throwsException{ ]sf1+3
Result result = userService.listUser(page); aHvsgp]
page = result.getPage(); 3.^Tm+ C
users = result.getContent(); ~-.^eT kP
return SUCCESS; +~~&FO2
} m2o)/:
|`50Tf\J
/** @&G< Np`
* @return Returns the page. ZC\&n4~7
*/ [c=T)]E1
public Page getPage(){ rIg5Wcd
return page; @h&crI[c
} Xob,jo}a
KNw{\Pz~w
/** `0qBuE_^h
* @return Returns the users. .h;PMY+
*/ *+wGXm
publicList getUsers(){ Pfv| K;3i
return users; ^bjaa
} ' `K-rvF,C
IV5B5Q'D
/**
=]auP{AlE
* @param page |dxcEjcY_
* The page to set. 1 ynjDin<
*/ T1&^IO-F7$
publicvoid setPage(Page page){ ief~*:5
this.page = page; Fu%%:3_
} ]U8VU
b+ g(=z+
/** a9=pZ1QAG
* @param users K3WhF
* The users to set. } 9qbF+b
*/ ?pAO?5Z:}
publicvoid setUsers(List users){ Vif0z*\e{
this.users = users; ]S=AO/'
} 0Ek+ }`
TL?(0]Hfe
/** 2unaK<1s
* @param userService MzY~-74aF
* The userService to set. dD Zds
k+!
*/ HaUfTQ8
publicvoid setUserService(UserService userService){ ZM~kc|&
this.userService = userService; xp4w9.X5(
} yl=_ /'*
} }95;qyQ$
E_[)z%&n2
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w^1!
4KkjBPV
,>^6ztM
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, <r{M(yZ?@
\VTNXEw*G
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 Q--VZqn
38[k o3
么只需要: Gw0_M&
java代码: 2'38(wXn#
nlfu y[oX
U60jkzIRH
<?xml version="1.0"?> $\DOy&e
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork dHtbl\6
kYVn4Wq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l^ @!,Z
Eep*,Cnt0
1.0.dtd"> @"\j]ZEnY
`Z}7G@ol
<xwork> uP:Y[$O
<#hltPyh
<package name="user" extends="webwork- kbxy^4"X
@LzqQ[
interceptors"> Zy>iaG9}
i09w(k?
<!-- The default interceptor stack name 4|Wglri
wQ4IQ!
--> 9 NO^ '
<default-interceptor-ref !w!}`|q
3y9K'
name="myDefaultWebStack"/> 7q' _]$
>z`^Q[
<action name="listUser" _msV3JBr
oj6b33z
class="com.adt.action.user.ListUser">
!IZbMn6
<param >~g(acH%`x
?3{R'Buv]
name="page.everyPage">10</param> l O)0p2
<result :< )"G&
q]-CTx$
name="success">/user/user_list.jsp</result> p;GT[Ds^
</action> d"1DE
4@qKML
</package> C;T:'Uws
=*AAXNs@3
</xwork> y}fF<qih'>
`+4>NT6cu9
,<^7~d{{3m
UogkQ& B
-7^A_!.
:%!}%fkxH
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 jAa{;p"jU
q*Hf%I"
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。 \,w*K'B_Y
U%Kv}s/(F{
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 D*>EWlZ
gbf-3KSp^
]kN<N0;\d
SG&VZY
%<g(EKl
我写的一个用于分页的类,用了泛型了,hoho 'E4`qq
!Od?69W, $
java代码: d ,Fj|}S
oBA]qI
H O^3v34ZO
package com.intokr.util; 6N{Vcfq
P <$)v5f
import java.util.List; Wz}8O]#/.
X}Ey6*D:
/** ~\4B 1n7
* 用于分页的类<br> ,Zpc vK/S
* 可以用于传递查询的结果也可以用于传送查询的参数<br> dFd^@b
* +>em
!~3
* @version 0.01 :QndeUw
* @author cheng GTj=R$%09
*/ o]&w"3vOP0
public class Paginator<E> { 9 >t
privateint count = 0; // 总记录数 9@Iz:!oqb
privateint p = 1; // 页编号 ')d&:K*M
privateint num = 20; // 每页的记录数 NF}QQwG3
privateList<E> results = null; // 结果 $[L8UUHY<8
P9Gjsu #
/** &B^zu+J
* 结果总数 yqy5i{Y
*/ (1
"unP-
publicint getCount(){ N2?o6)
return count; Vvth,
} 3'd(=hJ45$
){AtV&{$
publicvoid setCount(int count){ V~Zi #o
this.count = count; ]x8_f6;D
} h,Y!d]2w
L[]*vj
/** F:PaVr3q
* 本结果所在的页码,从1开始 u|!On
* 0ssKZ9Lc
* @return Returns the pageNo. &C~R*
*/ N1lhlw6
publicint getP(){ b8?qYm
return p; I)xB I~x
} e}x}Fj</(
r/X4Hy0!lT
/** LvWl*:z
* if(p<=0) p=1 ,0'Yj?U>
* ")/TbTVu
* @param p hX-([o
*/ vv2N;/;I
publicvoid setP(int p){ +GgJFBl
if(p <= 0) AL%gqt]
p = 1; *%G$[=
this.p = p; U~~Y'R\NU
} 1g_(xwUp+
6sRe. ct<