Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 QM'>)!8
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ,@t#)HV
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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 v9Ez0 :)
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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 #4!6pMW(&7
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分页支持类: G_?qY#"(
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java代码: zuvP\Y=V`
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package com.javaeye.common.util; K|.!)L
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import java.util.List; \K(#
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publicclass PaginationSupport { RTTEAh:.
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publicfinalstaticint PAGESIZE = 30; &qZ:"k
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privateint pageSize = PAGESIZE; ,YmTx
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privateList items; YCNpJGM
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privateint totalCount; ys|};*
}ABHGr5[
privateint[] indexes = newint[0]; xiQ;lE
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privateint startIndex = 0; ,U'E!?=:VS
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public PaginationSupport(List items, int `d:cq.OO
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totalCount){ n\H.NL)
setPageSize(PAGESIZE); 6-uB[$ko
setTotalCount(totalCount); Di #E m[
setItems(items); o<%s\n
setStartIndex(0); sxQMfbN
} G-sA)WOF
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public PaginationSupport(List items, int ]}dAm S/
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totalCount, int startIndex){ Q
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setPageSize(PAGESIZE); kM/;R)3t4/
setTotalCount(totalCount); ;923^*\:F{
setItems(items); >zB0+l
setStartIndex(startIndex); b
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} JV9Ft,xk
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public PaginationSupport(List items, int !Ql&Ls
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totalCount, int pageSize, int startIndex){ 6B>H75S+H
setPageSize(pageSize); /h73'"SpDy
setTotalCount(totalCount); Iw) 'Yyg
setItems(items); qluaop
setStartIndex(startIndex); f}F
} viR-h
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publicList getItems(){ k/V:QdD Sb
return items; 2u'h,on?
} "WHt9 yZ
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publicvoid setItems(List items){ bO?Us
this.items = items; C\p _
}
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publicint getPageSize(){ m;KD@E!
return pageSize; zAdZXa[MRY
} ;?0r,0l2$
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publicvoid setPageSize(int pageSize){ "+:IA|1wD
this.pageSize = pageSize; Se-n#
} "#a,R^J
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publicint getTotalCount(){ iu6NIy7D
return totalCount; $N)b6(}F10
} SV96eYT<
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publicvoid setTotalCount(int totalCount){ -|~tZuf
if(totalCount > 0){ A&6qt
this.totalCount = totalCount; C|Vz
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int count = totalCount / o2M4?}TpIV
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pageSize; |VD}:
if(totalCount % pageSize > 0) )$e_CJ}9e
count++; 7cJh^M
indexes = newint[count]; fbK`A?5K
for(int i = 0; i < count; i++){ LdM9k(
indexes = pageSize * F[5\
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i; b^]@8I[M
} /DBldL7yi
}else{ n:wZL&ZV0
this.totalCount = 0;
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} 1ti4 ZM
} 3A.T_mGCs
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publicint[] getIndexes(){ D/-$~u_o
return indexes; c$HZvv
} Td6"o&0A!
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publicvoid setIndexes(int[] indexes){ e[a?5,s2
this.indexes = indexes; :F`yAB3
} WMLsKoby
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publicint getStartIndex(){ R87e"m/C%
return startIndex; B> LL
*
} Ho; bgva
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publicvoid setStartIndex(int startIndex){ +Tw ]u`
if(totalCount <= 0) \6U$kMGde
this.startIndex = 0; $pg1Av7l
elseif(startIndex >= totalCount) yl[6b1
this.startIndex = indexes sjj*7i*
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[indexes.length - 1]; `vPc&.-K
elseif(startIndex < 0) u9}k^W)E
this.startIndex = 0; 'P^6H$0
else{ %>G(2)Fb\\
this.startIndex = indexes ;,yjkD[mWE
_ X*
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[startIndex / pageSize]; L'?0*t
} R2[-Q"|Ra
} u\zP`Y
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publicint getNextIndex(){ b:w {7
int nextIndex = getStartIndex() + ZNEWUt{+;^
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pageSize; (n,!v)
if(nextIndex >= totalCount) r g$2)z1
return getStartIndex(); +/E
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else F};G&
return nextIndex; 3M[b)At V.
} a!US:^}lu
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publicint getPreviousIndex(){ _#8OHG.x
int previousIndex = getStartIndex() - ZCbnDj
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pageSize; &gL &@';,
if(previousIndex < 0) 8T#tB,<fFW
return0; \%FEQa0u
else )Q%hd |R
return previousIndex; -}Iw!p#O3
} Uxyj\p
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} *uq}jlD`!
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抽象业务类 viJK%^U=-
java代码: wA#w]8SM
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/** *"pf3x6
* Created on 2005-7-12
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*/ H?(I-vO
package com.javaeye.common.business; &7 YTz3aj
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import java.io.Serializable;
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import java.util.List; o=1M<dL
u,R;=DNl
import org.hibernate.Criteria; z[I3k
import org.hibernate.HibernateException; `;9Z?]}`
import org.hibernate.Session; 9y~5@/32R
import org.hibernate.criterion.DetachedCriteria; nKzS2u=:Y
import org.hibernate.criterion.Projections; @,Iyn<v{B
import MyyNYZ
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org.springframework.orm.hibernate3.HibernateCallback; GuV.7&!x
import ,y+}0q-Ou
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org.springframework.orm.hibernate3.support.HibernateDaoS VqeK~,}
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upport; J(
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import com.javaeye.common.util.PaginationSupport; ]R$
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public abstract class AbstractManager extends B3lP#ckh
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HibernateDaoSupport { oA;sP'
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privateboolean cacheQueries = false; Vk/!_)
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privateString queryCacheRegion; 'V=i;2mB*
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publicvoid setCacheQueries(boolean tR,&|?0
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cacheQueries){ NT^m.o~4
this.cacheQueries = cacheQueries; LB1AjNJ
} YQ&Ww|xe
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publicvoid setQueryCacheRegion(String 6i6m*=h
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queryCacheRegion){ P,|%7'? Y
this.queryCacheRegion = ]>33sb
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queryCacheRegion; [=})^t?8
}
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publicvoid save(finalObject entity){ ne=?'e4
getHibernateTemplate().save(entity); _NfdJ=[Xh
} \lJCBb+k
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publicvoid persist(finalObject entity){ BP& T|s
getHibernateTemplate().save(entity); ]5V=kNui
} [p+]H?(A
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publicvoid update(finalObject entity){ Pp*:rA"N
getHibernateTemplate().update(entity); 8gQg#^,(t
} [O"9OW'2!B
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publicvoid delete(finalObject entity){ g H+s)6
getHibernateTemplate().delete(entity); |4J ;s7us
} 3KyIBrdi?
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publicObject load(finalClass entity, 1%v!8$
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finalSerializable id){ 59Lv/Mfy
return getHibernateTemplate().load Dsl,(qm5
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(entity, id); vn]e`O>y
} MY8[)<q"
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publicObject get(finalClass entity, KI@OEy
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finalSerializable id){ <sALA~p|0
return getHibernateTemplate().get 7Rba@ cs9
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(entity, id); U?bQBHIC
} PQ u_]cXI
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publicList findAll(finalClass entity){ >FVBn;1
return getHibernateTemplate().find("from {Dc{e5K
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" + entity.getName()); m| /?((s
} hU3!
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publicList findByNamedQuery(finalString v%ldg833l
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namedQuery){ BHNcE*U}@?
return getHibernateTemplate CAbeb+O
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().findByNamedQuery(namedQuery); .T2P%Jn.
} pR3@loFQ`o
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publicList findByNamedQuery(finalString query, UJ/=RBfkJ
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finalObject parameter){ %nRz~3X|+v
return getHibernateTemplate 9JDdOjqo
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().findByNamedQuery(query, parameter); F*}.0SQ
} w$aiVOjgT
X6T*?t3!9[
publicList findByNamedQuery(finalString query, \>DMN #
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finalObject[] parameters){ m]7oTmS
return getHibernateTemplate n$*e(
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;@Pd
().findByNamedQuery(query, parameters); !08\w@
} T5AoBUw
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publicList find(finalString query){ )YtdU(^J$
return getHibernateTemplate().find ?;bsg9
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(query); 33M10
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} SHAC(3o/e
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publicList find(finalString query, finalObject "f
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parameter){ 3pk=c-x
return getHibernateTemplate().find .|VWYN
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(query, parameter); u ?
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} *_ U=KpZF
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public PaginationSupport findPageByCriteria "PK`Ca@`v
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(final DetachedCriteria detachedCriteria){ <`f~Z|/-_(
return findPageByCriteria oEuV&m|yX
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); j><8V Qx
} z6Xn9
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public PaginationSupport findPageByCriteria Zv"qA
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(final DetachedCriteria detachedCriteria, finalint xoYaL
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startIndex){ >.76<fni
return findPageByCriteria smJ#.I6/L
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(detachedCriteria, PaginationSupport.PAGESIZE, L'@@ewA
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startIndex); K:JM*4W
} A7hWAq
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public PaginationSupport findPageByCriteria ssx#\
}#Q?\
(final DetachedCriteria detachedCriteria, finalint 6p}dl>T_y
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pageSize, j,J/iJs
finalint startIndex){ {SOy-
return(PaginationSupport) ~stG2^"[
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getHibernateTemplate().execute(new HibernateCallback(){ UWPzRk#s"
publicObject doInHibernate l2S1?*
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(Session session)throws HibernateException { 8wX|hK!Gz
Criteria criteria = ~\QN.a
)/Mk\``j
detachedCriteria.getExecutableCriteria(session); .!^}sp,E
int totalCount = }Y=X{3+~.
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((Integer) criteria.setProjection(Projections.rowCount Q$B\)9`v[
? JliKFD%
()).uniqueResult()).intValue(); T:G8xI1
P
criteria.setProjection 3yXSv1
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(null); 8ED}!;ZU
List items = Es^=&2''
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criteria.setFirstResult(startIndex).setMaxResults 5_yu4{@;y
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(pageSize).list(); +W}dO#
PaginationSupport ps = b&_u+g
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new PaginationSupport(items, totalCount, pageSize, X[;-SXq
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startIndex); S4!}7NOh
return ps; #sJL"GB
} ~1g)4g~
}, true); G1?m}{D)
} Mf_urbp]
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public List findAllByCriteria(final Ts c2;I
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DetachedCriteria detachedCriteria){ 6qYK"^+xu
return(List) getHibernateTemplate QZ?%xN(4
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().execute(new HibernateCallback(){ /@xL {
publicObject doInHibernate .{t]Mc
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(Session session)throws HibernateException { hha!uD~(
Criteria criteria = dZ;rn!dg>
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detachedCriteria.getExecutableCriteria(session); ^a #
return criteria.list(); U_oei3QP
} CeD(!1VG
}, true); v;$cx*?
} & Do|Hw
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public int getCountByCriteria(final [`/d$V!e
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DetachedCriteria detachedCriteria){ yE=tuHv(0
Integer count = (Integer) !IAd.<,
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getHibernateTemplate().execute(new HibernateCallback(){ p/4}SU
publicObject doInHibernate ?'%9
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(Session session)throws HibernateException { qV&ai {G:
Criteria criteria = _fmOTz G
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detachedCriteria.getExecutableCriteria(session); 'j oE-{
return {+@M!
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criteria.setProjection(Projections.rowCount 34s>hm=0.
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()).uniqueResult(); a$2WL g,
} a&)4Dv0
}, true); _a&Mk
return count.intValue(); <v+M ~"%V
} OtD!@GQ6
} F0 ^kUyF|
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用户在web层构造查询条件detachedCriteria,和可选的 ?I}0[+)V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Ou,Eu05jt'
& 8'QD~
PaginationSupport的实例ps。 y>iot e~
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ps.getItems()得到已分页好的结果集 _ H$^m#h
ps.getIndexes()得到分页索引的数组 y1*z,"dx
ps.getTotalCount()得到总结果数 GkYD:o=qx
ps.getStartIndex()当前分页索引 `bMwt?[*
ps.getNextIndex()下一页索引 S/H!a:_5r
ps.getPreviousIndex()上一页索引 QbG`F8dj
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l.AG^b
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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 :j4i(qcF
q A?j-H
一下代码重构了。 01AzM)U3"m
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我把原本我的做法也提供出来供大家讨论吧: * u{CnH
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首先,为了实现分页查询,我封装了一个Page类: 0$e]?]X6
java代码: y+K21(z.
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/*Created on 2005-4-14*/ B%^ $fJ|
package org.flyware.util.page; N%" /mcO
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/** zm`^=cV
* @author Joa {xS\CC(g
* ~ @Au <
*/ n3LCQ:]Tf
publicclass Page { xK;WJm"
elw}(l<F
/** imply if the page has previous page */ E])X$:P?
privateboolean hasPrePage; dt=5 Pnf[y
dX>l"))yR
/** imply if the page has next page */ tW7*(D
privateboolean hasNextPage; {nl4(2$
=`y.L5
/** the number of every page */ *3r{s'm
privateint everyPage; G>H',iOI
Kl)PF),
/** the total page number */ gt=
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privateint totalPage; fsVQZ$h73
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/** the number of current page */ G: p!PB>=
privateint currentPage; ' *x?8-K P
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/** the begin index of the records by the current M+q|z0 U
~.'NG?
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query */ 1XvB,DhJ
privateint beginIndex; 2gC.Z:}
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/** The default constructor */ `fUem,$)1F
public Page(){ <D!\"C
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} KN"V(<!)~
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/** construct the page by everyPage v4V|j<R
* @param everyPage 8LouCv(>
* */ 5
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public Page(int everyPage){ /92m5p
this.everyPage = everyPage; sG~5O\,E
} h0)Wy>B=,
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/** The whole constructor */ Tfba3+V
public Page(boolean hasPrePage, boolean hasNextPage, s]p3dB#
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int everyPage, int totalPage, 9G'Q3?
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int currentPage, int beginIndex){ D{!NTr
this.hasPrePage = hasPrePage; "77 j(Vs9
this.hasNextPage = hasNextPage; !SFF 79$c
this.everyPage = everyPage; R;*3";+v|:
this.totalPage = totalPage; N>$Nw<wV
this.currentPage = currentPage; t6)wR
this.beginIndex = beginIndex; ,Uh7Q-vd
} /o19/Pvwm
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/** ~+GMn[h
* @return UEvRK?mm=
* Returns the beginIndex. 9V%s1@K
*/ Ba],ONM4k
publicint getBeginIndex(){ *CH lg1
return beginIndex; oKJj?%dHK9
} PB :Lj
e Ert_@}
/** =O)dHY}
* @param beginIndex !PzlrH)M=p
* The beginIndex to set. u!X$M?D4
*/ uW8LG\Z>D5
publicvoid setBeginIndex(int beginIndex){ [ Yzh(a8
this.beginIndex = beginIndex; coxMsDs
} #.(6.Li
J=gerdIk
/** [8VB"{{&
* @return s C9j73vf
* Returns the currentPage. tCk;tu!d
*/ Vc!;O9dP
publicint getCurrentPage(){ 'j)xryw
return currentPage; 0.~Pzg
} w6fVZY4
76\ir<1up
/** eoS8e$}
* @param currentPage \wxS~T<&L
* The currentPage to set. ]Xur/C2A
*/ pv=g)
publicvoid setCurrentPage(int currentPage){ ;^Vsd\ac0
this.currentPage = currentPage; K>h=
} 8gv\`
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/** @}K'Ic
* @return T
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* Returns the everyPage. L44/eyrp
*/ 3+<}Hm+
publicint getEveryPage(){ !po8[fz~x
return everyPage; <|M cE
} 0@yHT-Dy
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/** cp0@wC#d
* @param everyPage 8Vkw
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* The everyPage to set. gsn3]^X
*/ O;9'0-F ?
publicvoid setEveryPage(int everyPage){ -;TqdL@
this.everyPage = everyPage; ?*~W
} ThX%Uzd"[;
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/** x.CNDG
* @return /HsJyp+t
* Returns the hasNextPage. *7Ct#GC
*/ %pNK ?M+
publicboolean getHasNextPage(){ -v4kW0G
return hasNextPage; a
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} ,%#FK|
YK/?~p9:
/** |hjm^{!TpW
* @param hasNextPage ~n$VCLa
* The hasNextPage to set. fPf8hz>
*/ ca@0?q#
publicvoid setHasNextPage(boolean hasNextPage){ 9Xt5{\PJ
this.hasNextPage = hasNextPage; ErK5iTSD
} -aDGXQM{~
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/** oZxC.;xJ
* @return kzqW&`xn?
* Returns the hasPrePage. ;Ft_ Xiq
*/ LMf_wsp
publicboolean getHasPrePage(){ }1P>^I"[Y
return hasPrePage; |*W`}i
} JzJS?ZF
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/** wK+%[i&,
* @param hasPrePage N/QTf1$
* The hasPrePage to set. Z~o6%_xe
*/ _-$"F>
publicvoid setHasPrePage(boolean hasPrePage){ lCBb0k2
this.hasPrePage = hasPrePage; cF9bSY_Eh
} Xm./XC
P08=?
/** +1R?R9^Fw
* @return Returns the totalPage. n0_q-8r
* R _WP r[P
*/ CfKvC
publicint getTotalPage(){ *Ppb;
return totalPage; eXY*l>B
} dd#=_xe
\jDD=ew
/** ufE;rcYE
* @param totalPage >NWrT^rk
* The totalPage to set. yrOWC
*/ ?!=yp#
publicvoid setTotalPage(int totalPage){ :DTKZ9>2D
this.totalPage = totalPage; 095:"GvO
}
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h?
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} JsohhkJNGi
cRPW
;/w-7O:
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?.d6!vA
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个PageUtil,负责对Page对象进行构造: q(sEN!^L`
java代码: =e2|:Ba!
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/*Created on 2005-4-14*/ u`I&&
package org.flyware.util.page; ;i*<HNQ
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import org.apache.commons.logging.Log; "]\sw"zO?
import org.apache.commons.logging.LogFactory; D#}t)$"
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/** d[mmwgSR?I
* @author Joa v?e@`;-
<
* F?#^wm5TZ
*/ 6-8,qk
publicclass PageUtil { xj8yQ Y1
0$)uOUVJ
privatestaticfinal Log logger = LogFactory.getLog HBHDu;u
\$GM4:R D
(PageUtil.class); mw2/jA7
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/**
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* Use the origin page to create a new page 32nB9[l
* @param page a *?bnw?
* @param totalRecords nBw4YDR!
* @return {~J'J $hn8
*/ coa+@g,w7#
publicstatic Page createPage(Page page, int t5:
1' N9P
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totalRecords){ z,pKyInw
return createPage(page.getEveryPage(), = F*SAz
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page.getCurrentPage(), totalRecords); }LK +w+h~
} g=*'kj7c3
A[W3.$s
/** h9<*+T
* the basic page utils not including exception 6Ih8~Hu
g{|F<2rd[m
handler \4$V;C/n,
* @param everyPage ncw)VH;_-
* @param currentPage SI_u0j4%*
* @param totalRecords uG-t)pej
* @return page ykAZP[^'
*/ F|mppY'<J
publicstatic Page createPage(int everyPage, int Y:f"Zx
u^2)oL
currentPage, int totalRecords){ kAc8[Hn
everyPage = getEveryPage(everyPage); [;6,lI}
currentPage = getCurrentPage(currentPage); C_CUk d[
int beginIndex = getBeginIndex(everyPage, (*qMs)~]B
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currentPage); 4FwtC"G3
int totalPage = getTotalPage(everyPage, 7]\_7L|>]
h 8Shf"
totalRecords); g$X4ZRSel
boolean hasNextPage = hasNextPage(currentPage, b&wyp@k
KZeaM
totalPage); ^w|D^F=o
boolean hasPrePage = hasPrePage(currentPage); iO$Z?Dyg9
;og[q
returnnew Page(hasPrePage, hasNextPage, olA 1,8
everyPage, totalPage, -hy`Np
currentPage, %=w@c
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beginIndex); {"rYlN7,
} {&u`d.Lk2p
2!@ER i
privatestaticint getEveryPage(int everyPage){ 0c{-$K}
return everyPage == 0 ? 10 : everyPage; q>X30g
} JWB3;,S
AFM Ip^F
privatestaticint getCurrentPage(int currentPage){ dd?ZQ:n
return currentPage == 0 ? 1 : currentPage; _P].Z8
} IA6,P>}N
qoZUX3{
privatestaticint getBeginIndex(int everyPage, int 0NB5YQ8_]
S/?!ESW6
currentPage){ FdwlRu G
return(currentPage - 1) * everyPage; \d:AV(u
} 5xb1FH d:
P3e}G-Oz
privatestaticint getTotalPage(int everyPage, int :"G x
{7F?30: ]
totalRecords){ +HAd=DU
int totalPage = 0; [B_(,/?
&$H7vdWNy
if(totalRecords % everyPage == 0) RyuI2jEy
totalPage = totalRecords / everyPage; NzBX2
else 0&21'K)pW
totalPage = totalRecords / everyPage + 1 ; mMt~4(5
+uqP:z
return totalPage;
dj}y6V&
} "|,;~k1
,$oz1,Q/
privatestaticboolean hasPrePage(int currentPage){ A?zxF5rfp
return currentPage == 1 ? false : true; =NNA7E7c
} XYrZI/R
|'+ [ '
privatestaticboolean hasNextPage(int currentPage, $ca>bX]
Id}@
int totalPage){ 6+.8nx:9X
return currentPage == totalPage || totalPage == Jf</83RZ
WHk rd8
0 ? false : true; w~a_FGYX
} iJaA&z5sr
n/
m7+=]v
7eU|iDYo
} ^630%YO
(?ofL|Cg(
e$Npo<u
vyhxS .[9
9{-
Sa
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。 SbYsa
zNh$d;(O$^
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 .dw;b~p
:k&5Z`>)
做法如下: _GtG8ebr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 lm[LDtc
8|2I/#F}]
的信息,和一个结果集List: }uo.N
java代码: -<Oy5N
?ISv|QpC
%CaF-m=Pq
/*Created on 2005-6-13*/ x6iT"\MO
package com.adt.bo; ^v+7IFn
*Q`y'6S
import java.util.List; d@QC[$qXj
0(h'ZV
import org.flyware.util.page.Page; egHvI&w"o
n[c/L8j
/** &{=`g+4n
* @author Joa V|T3blG?D
*/ uc?`,;8{`
publicclass Result { {!av3Pz\
=JDa[_lpN
private Page page; .NX>d@
Kc
'kE^oX_
private List content; ~'u %66
TM*<hC
/** k1sR^&{l
* The default constructor j"J[dlm2M
*/ R1j)0b6cQ%
public Result(){ R2B0?fu
super(); ptCAtEO72
} ;Y@"!\t}
zKf.jpF^
/** R1/87eB
* The constructor using fields > Du>vlTY
* 'i7!"Y6>
* @param page \!Fx,#r$7-
* @param content uEE#A0
*/ k_A
9gj1
public Result(Page page, List content){ 0o*
this.page = page; ;Y"*Z2U
this.content = content; H'2Un(#Al
} eGW~4zU
RxrUnMF
/** c
;@k\6
* @return Returns the content. YA'_Ba(v)
*/ jb
{5
publicList getContent(){ "PtOe[Xk
return content; 9xZ?}S:d
} (U@uJ
S/)J<?<b
/** X!=*<GF)
* @return Returns the page. r<XlIi
*/ I]B[H6
public Page getPage(){ 0ofl,mXW
return page; t^(#~hx
} 1Yb9ILX[J
BdYl
sYp
/** > qDHb'
* @param content @"$rR+r'
* The content to set. Ymr\8CG/
*/ >x6$F*:W}
public void setContent(List content){ K" U!SWv
this.content = content; a8[Q1Fa4|
} g$eZT{{W
R`F8J}X_
/** .|Bmg6g*
* @param page \&)k{P>=
* The page to set. 0Q= o"@
*/ GK.U_` 4?
publicvoid setPage(Page page){ 8~s-@3J
this.page = page; AcCM
W@e
} `h+1u`FJ
} u,Rhm-`
Vo-]&u&cr
4}t&AW4
v*.#LJEm
DfL>fk
2. 编写业务逻辑接口,并实现它(UserManager, AG==A&d>$
4t;m^Iv
UserManagerImpl) d;c<" +
java代码: kn 1+lF@
A_\ZY0Xt
sJ(q.FRM'
/*Created on 2005-7-15*/ A[.5Bi
package com.adt.service; D8I)3cXa'
zcTY"w\b
import net.sf.hibernate.HibernateException; :1JICxAU
qf
qp}g\
import org.flyware.util.page.Page; Y
=BXV7\
afWEt -
import com.adt.bo.Result; `+go|
5N2
Q8sCI An{
/**
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* @author Joa HxmCKW!
*/ YvP u%=eF
publicinterface UserManager { [
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_Mis-K:]{?
public Result listUser(Page page)throws B hnwb0b<
NXyuv7%5=
HibernateException; te b~KM
~jqh&u$(
} =*u:@T=d5
Gr
a(DGX
VSI.c`=,
yt-F2Z&
wc
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v /A
java代码: LpJ_HU7@lk
$*u{i4b
<Gr775"
/*Created on 2005-7-15*/ }nW) +
package com.adt.service.impl; ,UD,)ZPf[
ecI[lB
import java.util.List; E*t0ia8
&_!g|-
import net.sf.hibernate.HibernateException; 2\,vq
R
5E#koy7
$s
import org.flyware.util.page.Page; fWBI}~e
import org.flyware.util.page.PageUtil; u+RdC;_
sN
`NZyG
import com.adt.bo.Result; bof{R{3q
import com.adt.dao.UserDAO; cP~?Iz8nD
import com.adt.exception.ObjectNotFoundException; s: .5S
import com.adt.service.UserManager; &Z^,-Y
{=NHidi~
/** ,6%{9oW9Z:
* @author Joa X|WAUp?
*/ y&.[Nt '+
publicclass UserManagerImpl implements UserManager { zDk^^'
v$`AN4)}
private UserDAO userDAO; Odo"S;)
-;?5<>zZ
/** w]{NaNIeq1
* @param userDAO The userDAO to set. }0({c~z\
*/ ]bq<vI%
publicvoid setUserDAO(UserDAO userDAO){ 8 '2lc
this.userDAO = userDAO; +c699j;[
} R":nG7o
p5KM(N6f
/* (non-Javadoc) f]BG`rJX
* @see com.adt.service.UserManager#listUser E&/D%}Wl
"5-S:+
(org.flyware.util.page.Page) hOX$|0i
*/ 1MV\
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public Result listUser(Page page)throws [Q/')5b
U?6YY`A8
HibernateException, ObjectNotFoundException { BHwQB2t gc
int totalRecords = userDAO.getUserCount(); cs ?@Ri=g
if(totalRecords == 0) jG3}V3|.
throw new ObjectNotFoundException S"iQQV{)Z
vYD>m~Qc^
("userNotExist"); {9<2{$Og
page = PageUtil.createPage(page, totalRecords); l.i"Z pik
List users = userDAO.getUserByPage(page); *mM+(]8US
returnnew Result(page, users); bT@7&
} V;Zp3Qo!
!Cj1:P
} :zC'jceO
_[SP*"
]H
N.q4Ar[x#p
1:%m
>4U
<[^nD>t_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 yiUJ!m
2O|o%`?
询,接下来编写UserDAO的代码: FxKb
3. UserDAO 和 UserDAOImpl: G6zFCgFJ^y
java代码: gz[Ng> D+
V 'Gi2gNaP
E (M\U5o:
/*Created on 2005-7-15*/ $J#}3;a
package com.adt.dao; \<VwGbzFi
?S8cl7;+
import java.util.List; Y962rZ
j\nnx8`7
import org.flyware.util.page.Page; RGGP6SDc
&50Kn[
import net.sf.hibernate.HibernateException; )S$!36Ni[
N1Y*IkW"
/** VwoCRq*
* @author Joa (~TP
*/ t%Z_*mIfmE
publicinterface UserDAO extends BaseDAO { ??rx\*,C</
,z)7rU`
publicList getUserByName(String name)throws @T1/S&F=
$7aR f'
HibernateException; lC6#EU;
Kbc-$oneR
publicint getUserCount()throws HibernateException; L_jwM^8
_Bh-*l?K>
publicList getUserByPage(Page page)throws o(~>a
piO+K!C0n:
HibernateException; c3|;'s
yov:JnWo
} [^W4%S
\1RQ),5 %]
cW),Y|8
!+ IxPn
c?d+>5"VX
java代码: 4i[3|hv'
+I2P{7
0-g,C=L
/*Created on 2005-7-15*/ K+H?,I
package com.adt.dao.impl; Z>a_vC
b]mRn{r?
import java.util.List; DB_
x
71Ssk|L
import org.flyware.util.page.Page; 9U58#
/U)w:B+p/g
import net.sf.hibernate.HibernateException; K4xZT+Qb
import net.sf.hibernate.Query; %yQ-~T@
*ZGQ`#1.X6
import com.adt.dao.UserDAO; mCtuyGY
)xP]rOT
/** ~@z5Ld3xz
* @author Joa @P"q`*
*/ )G
,LG0"-
public class UserDAOImpl extends BaseDAOHibernateImpl Z8kO*LYv
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implements UserDAO { bqf=;N vog
X8bo?0
/* (non-Javadoc) Lq
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* @see com.adt.dao.UserDAO#getUserByName )TM ![^d
+:It1`A~]
(java.lang.String) +F 6KGK[
*/ D}!U?]la&
publicList getUserByName(String name)throws {C*mn !u
(7}v}3/
HibernateException { ms
;RJT2O'
String querySentence = "FROM user in class 3Du&KZ
u!nt0hS
com.adt.po.User WHERE user.name=:name"; I_#)>%H
Query query = getSession().createQuery nH% /
y~1UU3k5
(querySentence); Ft`#]=IS
query.setParameter("name", name); pWps-e
return query.list(); e7/J:n$
} Bi
kCjP[b
b]Rn Cu"
/* (non-Javadoc) 9A3Q&@,
* @see com.adt.dao.UserDAO#getUserCount() &)fPz-s
*/ 4pq >R
publicint getUserCount()throws HibernateException { ?Dm! ;Z+7
int count = 0; H:9(
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String querySentence = "SELECT count(*) FROM DfV_08
wGISb\rr
user in class com.adt.po.User"; f|6%71
Query query = getSession().createQuery ?ArQ{9c
X.Z?Ie
(querySentence); v_5DeaMF'
count = ((Integer)query.iterate().next sNX$ =<E
R,Tw0@{O*
()).intValue(); %DPtK)X1
return count; $j{ynh)^
} R) @k|
d-N<VVcy\
/* (non-Javadoc) ])~*)I~Y
* @see com.adt.dao.UserDAO#getUserByPage 3QUe:8
D9H|]W ~
(org.flyware.util.page.Page) <ze'o.c
*/ C)#:zv m
publicList getUserByPage(Page page)throws aQFYSl
f
21w`Uk48
HibernateException { 1 ,D2][
String querySentence = "FROM user in class "!Mu5Ga
uaJ5'*
com.adt.po.User"; A7|"0*62
Query query = getSession().createQuery #wM0p:<
.D4D!!
(querySentence); $!obpZ~ }
query.setFirstResult(page.getBeginIndex()) v
l{hE~
.setMaxResults(page.getEveryPage()); -+Q,xxu
return query.list(); "[GIW+ui
} 4sZ^:h,1
>454Yir0Mk
} T| 4c\
KDQux
<hy>NM@$
s|,gn 5
X[Y!=e4z
至此,一个完整的分页程序完成。前台的只需要调用 4eaC18?
4f"be
userManager.listUser(page)即可得到一个Page对象和结果集对象 VIi|:k
L1rov
的综合体,而传入的参数page对象则可以由前台传入,如果用 Xx?Jt
Vaq=f/
webwork,甚至可以直接在配置文件中指定。 #M`ijN!Y
3<JZt.|
下面给出一个webwork调用示例: "_#%W
oo
java代码: z=ppNP0
Nb]qY>K
)b!q
/*Created on 2005-6-17*/ 'a"<uk3DT
package com.adt.action.user; ZQ20IY|,
-'q=oTZ
import java.util.List; m"x~Fjvd
9=<
Z>
import org.apache.commons.logging.Log; z9dVT'
import org.apache.commons.logging.LogFactory; E>'pMw
import org.flyware.util.page.Page; NoYu"57\
zo\XuoZ
import com.adt.bo.Result; @1n
import com.adt.service.UserService; ?;{A@icr
import com.opensymphony.xwork.Action; 4F:RLj9P!
L</"m[
/** Brpin
* @author Joa AQ0L9?
*/ &S|laqH
publicclass ListUser implementsAction{ JHO9d:{-
*Z/B\nb
privatestaticfinal Log logger = LogFactory.getLog "
*Ni/p$I
9m6w.:S
(ListUser.class); *$l8H[
jH:*x$@
=
private UserService userService; 6 #{=
E@
`kj7I{'l%9
private Page page; j 6v +S
&F.lo9JJ
privateList users; 4G`YZZQ
B:x4H}`vh
/* 7Q[P
* (non-Javadoc) WMUw5h
* ]e"NJkcm
* @see com.opensymphony.xwork.Action#execute() E-"Jgq\aC
*/ MESQAsx%
publicString execute()throwsException{ }W|CIgF*
Result result = userService.listUser(page); gJF;yW4
page = result.getPage(); 'QW 0K]il
users = result.getContent(); #x%O0
return SUCCESS; {UPIdQ'g
} HQUL?URt
41C=O@9m
/** ?xG #4P<C=
* @return Returns the page. +>:X4A*
*/ ;\&7smE[
public Page getPage(){ T Z>z5YTv
return page; $x2<D :
} vF([mOZ
`$#64UZ>U1
/** :YV!;dKJ
* @return Returns the users. <N`rcKE%~P
*/ j5/H#_.
publicList getUsers(){ 75v*&-
return users; RyM2CQg[
} 6Q wL
`zsKc 6%
/** ]mqB&{g
* @param page u>? VD%
* The page to set. (ZI&'"H
*/ I'yhxymZ;
publicvoid setPage(Page page){ 74[}AA
this.page = page; a\MU5%}\
} }h]:I'R!
6 8_UQ.
/** )0'O!O
* @param users <A6<q&g|E
* The users to set. "3>#[o
*/ hB^"GYZ
publicvoid setUsers(List users){ f'.yM*
this.users = users; j<gnh
} }3i@5ctQ
:#|77b0
/** \NSwoP
* @param userService ?=T&|pp
* The userService to set. j1d=$'a "
*/ ,~kMkBkl~
publicvoid setUserService(UserService userService){ 43VuH
this.userService = userService; +V7p?iEY
} uC}YKT>V7
} Cy2X>Tl"<E
Mz{>vb
My1E@<
AzQ}}A;TSx
4%]{46YnK
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, jBB<{VV|
-0Q!:5EC
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 $zbg
r8>
q*0~s
么只需要: ; 6zu!
java代码: p1D-Q7F
!C+25vup
Wx-{F
<?xml version="1.0"?> ilHj%h*z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork !#?tA/t@
<
xV!vN
1.0//EN" "http://www.opensymphony.com/xwork/xwork- tN0>5'/
G.N3R
1.0.dtd"> I2/wu(~>
3&zmy'b*:
<xwork> f2Slsl;
C[Fh^
<package name="user" extends="webwork- zZ wD)p?_g
CkflEmfe
interceptors"> #&/*ll)
iN)@Cu7
<!-- The default interceptor stack name Gmc"3L
yZ P+
--> |_rj12.xo
<default-interceptor-ref p;H1,E:Re#
D\TL6"wo
name="myDefaultWebStack"/> Op0
#9W
:V"}"{(6
<action name="listUser" jIW:O
duqu}*Jw
class="com.adt.action.user.ListUser"> ]#q dA(Kl
<param &0lNj@/
kP6r=HH@
name="page.everyPage">10</param> l&yR-FJ7KY
<result <)&ykcB
ruW6cvsvet
name="success">/user/user_list.jsp</result> (+U!#T]'D
</action> ML]?`qv '
}s|v-gRM{
</package> &]M<G)9
5N6%N1
</xwork> `BvcIn4do
n}+
DO6J
nxJhK
T
v{jl)?`~w
?L
$KlF Y
&O[o;(}mFI
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 &sllM
N7;2BUIXJ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 M-Js"cB[
o+vf
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 YnMph0\Y^
bw[!f4~
>i.+v[)#
(5I]um tge
m1<B6*iG"
我写的一个用于分页的类,用了泛型了,hoho );6zV_^!
3646.i[D
java代码: Y'Af I^K
|#sP1w'l]
Vr^wesT\Hx
package com.intokr.util; N8vWwN[3
9UwDa`^
import java.util.List; \i&yR]LF
EbW7Av
/** j`
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* 用于分页的类<br> LY|h*a6Ym
* 可以用于传递查询的结果也可以用于传送查询的参数<br> J^W.TM&q$,
* 1idEm*3&(
* @version 0.01 :{fsfZXXr
* @author cheng S*]IR"YL
*/ <O*q;&9
public class Paginator<E> { !1l2KW<be
privateint count = 0; // 总记录数 dfrq8n]
privateint p = 1; // 页编号 !!QMcx_C#/
privateint num = 20; // 每页的记录数 EmH{G
privateList<E> results = null; // 结果 ucn aj|
mkWIJH
/** !pN,,H6Y
* 结果总数 X3"V1@-i4$
*/ mA4v 4z
publicint getCount(){ 4j | vzyc
return count; lDH0bBmd0
} Qj=l OhM
R_*\?^k|A
publicvoid setCount(int count){ "L,FUo^&
this.count = count; %'>. R
} $a-~ozr`C
`KL`^UqR
/** 8'?e4;O
* 本结果所在的页码,从1开始 -r,J>2`l
* \\'!<Bn2d
* @return Returns the pageNo. ^GbyA YEp
*/ eL(T
publicint getP(){ X23TS`
return p; :?S2s Ne2
} 2"mO"2d%
/0r2v/0
/** RFZrcM
* if(p<=0) p=1 Q~]R#S
* 9xSAWKr,l
* @param p 7Ua
Ll
*/ & .#0jb1r
publicvoid setP(int p){ a@ lK+t
if(p <= 0) w3& F e=c
p = 1; c_".+Fa
this.p = p; $$8"i+,K
} 9LFg":
9(iJ=ao (
/** pymT-
* 每页记录数量 :l6sESr
*/ rdC(+2+Ay
publicint getNum(){ Q!"Li
return num; nc3 1X
} :;JJvYIs
[<%yU y
/** u54+oh|,M
* if(num<1) num=1 $;@s
*/ l"MEX/
publicvoid setNum(int num){ K=~h1qV:
if(num < 1) w,l1&=d
num = 1; "'PDreS
this.num = num; xLGAP-mx]
} C!.6:Aj
:n>h[{o%
/** ! g}9xIL
* 获得总页数 !q/?t XM!
*/ KN%Xp/lkX
publicint getPageNum(){ Q0r_+0[7j
return(count - 1) / num + 1; <}UqtDF 0
} ")LF;e
W0?yPP=.
/** J%}}(G~
* 获得本页的开始编号,为 (p-1)*num+1 {o]OxqE@
*/ bFTWuM
publicint getStart(){ Xu'u"amt
return(p - 1) * num + 1; PM_q"}-
} ypml22)kz
v&?Bqj
/** xWV_Do)z
* @return Returns the results. xi.;`Q^#
*/ hTy#Q.=
publicList<E> getResults(){ 7?kvrIuY&
return results; s{CSU3vYmi
} Z1>pOJm
PvA%c<z
public void setResults(List<E> results){ EJ86k>]
this.results = results; R{*p\;
} SQliF[-
PanyN3rC*
public String toString(){ CUYp(GU
StringBuilder buff = new StringBuilder zZDr=6|r_
yP"_j&ef7
(); is`a_{5e=
buff.append("{"); ?$o8=h
buff.append("count:").append(count); Jw86P=
buff.append(",p:").append(p); 2x`#
f0[
buff.append(",nump:").append(num); m=n
V$H
buff.append(",results:").append 1dKLNE
#}A!Bk
(results); {~=[d`t
buff.append("}"); FS20OD
return buff.toString(); =,(Ba'
} 3kJAaI8
R!,RZ?|v
} S4tdWA
ah}aL7dgO
F 6SIhf.;