Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >}?jO B
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 P|j|0o,8p
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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 \no6]xN;
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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 Zaime
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分页支持类: fab.%$
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java代码: vbBNXy/
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package com.javaeye.common.util; p>oC.[:4a
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import java.util.List; "%peYNZ&%
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publicclass PaginationSupport { 76::X:76
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publicfinalstaticint PAGESIZE = 30; _+7+90u
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privateint pageSize = PAGESIZE; (1IYOlG4
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privateList items; QHU|aC{r
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privateint totalCount; p~'iK4[&6
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privateint[] indexes = newint[0]; 6;:z?Q
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privateint startIndex = 0; Yyx sj9
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public PaginationSupport(List items, int Y-?0!a=e.
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totalCount){ r=Tz++!
setPageSize(PAGESIZE); HOaNhJ{7D
setTotalCount(totalCount); JtvZ~s
setItems(items); q\pI&B
setStartIndex(0); 6b2Z}B
} |` |#-xu
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public PaginationSupport(List items, int Z)&!ZlM
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totalCount, int startIndex){ Ko|m<;LX
setPageSize(PAGESIZE); Y1Q240
setTotalCount(totalCount); k=W~ot&
setItems(items); )-\C{>
setStartIndex(startIndex); ]-j.\+(*
} oBO4a^D
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public PaginationSupport(List items, int PZ>(cvX&
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totalCount, int pageSize, int startIndex){ X L3m#zW&
setPageSize(pageSize); J Bgq2
setTotalCount(totalCount); ["fUSQ
setItems(items); tVv/G~(
setStartIndex(startIndex); ))%f"=:wt
} U)[LKO1
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publicList getItems(){ -aq3Lqi
return items; ?6Wv["%
} =,b6yV+$D
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publicvoid setItems(List items){ )IVk4|
this.items = items; %9
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} ^Gi7th,
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publicint getPageSize(){ v M'!WVs
return pageSize; t`1M}}.
} #iKPp0`K*
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publicvoid setPageSize(int pageSize){ g`z;:ao
this.pageSize = pageSize; E~@&&dU8
} '7Mz]@
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publicint getTotalCount(){ GbC@ |
return totalCount; BG6.,'~7o
} -5oYGLS$y3
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publicvoid setTotalCount(int totalCount){ fig~z=m
if(totalCount > 0){ (mr*Thy`@
this.totalCount = totalCount; +zwS[P@
int count = totalCount / :_,a%hb+8
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pageSize; Yy~xNj5OS
if(totalCount % pageSize > 0) -9~$Ll+2h
count++; ?)ct@,Ek$
indexes = newint[count]; .i {yW
for(int i = 0; i < count; i++){ 2TG2<wqvE
indexes = pageSize * 1M.#7;#B3
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} $Zr \$z2
}else{ &pQ[(|=(
this.totalCount = 0; M]|]b-#
} Y<IuwS
} Ee_?aG
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publicint[] getIndexes(){ k`#E#1niN
return indexes; -X_\3J
} _&(L{cFx6
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publicvoid setIndexes(int[] indexes){ Oq$-*N
this.indexes = indexes; 6.9C4
} d~MY
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publicint getStartIndex(){ @3y
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return startIndex; NT2XG&$W>
} kh@O_Q`j
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publicvoid setStartIndex(int startIndex){ ?2_h.
if(totalCount <= 0) =;GmLi3A
this.startIndex = 0; q %j8Js
elseif(startIndex >= totalCount) {Q[ G/=mx
this.startIndex = indexes 9B![l=Gh
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[indexes.length - 1]; }.(DQwC}1k
elseif(startIndex < 0) z;?ztpa@
this.startIndex = 0; CDF;cM"td
else{ ,{\Ae"{6
this.startIndex = indexes q{Gh5zg5O
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[startIndex / pageSize]; +1I7K|M
} _xH<R
} QOgGL1)7-
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publicint getNextIndex(){ 3-E-\5I
int nextIndex = getStartIndex() + ~+d{:WY
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pageSize; Tay$::V
if(nextIndex >= totalCount) !vSq?!y6*P
return getStartIndex(); /NjBC[P
else auB
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return nextIndex; :{^~&jgL
} w#hg_RK(Jr
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publicint getPreviousIndex(){ &^K(9"
int previousIndex = getStartIndex() - :Tv>)N
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pageSize; 7x77s
if(previousIndex < 0) `\|@w@f|;
return0; Nmd{C(^o
else St(jrZb
return previousIndex; $&qLrKJ
}
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} ZXL'R|?
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抽象业务类 6`iYIXnz
java代码: *zN~x(0{E
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/** }Xk_
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* Created on 2005-7-12 Sk"hqF.2
*/ ~QlF(@ue
package com.javaeye.common.business; #AP;GoIf"j
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import java.io.Serializable; OiXO<1'$
import java.util.List; .gGO+8[N*
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import org.hibernate.Criteria; mA$86 X_
import org.hibernate.HibernateException; 1=5HQ~|[TO
import org.hibernate.Session; Z9NND
import org.hibernate.criterion.DetachedCriteria; 3bXfR,U
import org.hibernate.criterion.Projections; 7.Z-
import h)fsLzn]Tf
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org.springframework.orm.hibernate3.HibernateCallback; jjQDw=6
import q9p31b3
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org.springframework.orm.hibernate3.support.HibernateDaoS D
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upport; wkPjMmW+!
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import com.javaeye.common.util.PaginationSupport; qy.$5-e:[9
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public abstract class AbstractManager extends !;mn]wR>a
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HibernateDaoSupport { yGNpx3H
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privateboolean cacheQueries = false; rNJU &
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privateString queryCacheRegion; !hM`Oe`S
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publicvoid setCacheQueries(boolean !ht2*8$lQ
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cacheQueries){ 4eB oR%2o
this.cacheQueries = cacheQueries; 6it
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} u?fM.=/N
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publicvoid setQueryCacheRegion(String 0G-obHe0
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queryCacheRegion){ EI*~VFx
this.queryCacheRegion = P
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queryCacheRegion; ?<^8,H
} d/F^ez
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publicvoid save(finalObject entity){ WEX7=^k9
getHibernateTemplate().save(entity); 8f[ztT0`g
} [ dVBsi
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publicvoid persist(finalObject entity){ kppi>!6
getHibernateTemplate().save(entity); QEbf]U=
} AD<>)(
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publicvoid update(finalObject entity){ .tGz, z}
getHibernateTemplate().update(entity); vV$t`PEY
} LQr!0p.i"
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publicvoid delete(finalObject entity){ jSHFY]2
getHibernateTemplate().delete(entity); 6;:D!},'c
} .%7Le|Fb"
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publicObject load(finalClass entity, {DKZ~
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finalSerializable id){ \-]tvgA~&
return getHibernateTemplate().load n.a2%,|v
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(entity, id); 6,jCO@!
} 1eV&oN#
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publicObject get(finalClass entity, ?B;7J7 T
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finalSerializable id){ m:`M&Xs&
return getHibernateTemplate().get - E GZ
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(entity, id); {wA8!5Gu
} k7rg:P
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publicList findAll(finalClass entity){ <yX u!
return getHibernateTemplate().find("from wMN{ 9Ce3j
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" + entity.getName()); [pp|*@1T
} Y DHP-0?
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publicList findByNamedQuery(finalString XD8I.q
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namedQuery){ ~7KH/%Z-
return getHibernateTemplate -Z:x!M[Xr
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().findByNamedQuery(namedQuery); <'$>&^!^
} 7]1a3Jk
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publicList findByNamedQuery(finalString query, hx;kNcPbI
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finalObject parameter){ 1aIGC9xQ`
return getHibernateTemplate 4FZR }e\
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().findByNamedQuery(query, parameter); k'|yUJ,
} +x`pWH]2
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publicList findByNamedQuery(finalString query, XKZsX1=@R
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finalObject[] parameters){ !',%kvJI
return getHibernateTemplate b/m.VL
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().findByNamedQuery(query, parameters); {D",ao
} @ewi96
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publicList find(finalString query){ #"!ga)a%L
return getHibernateTemplate().find Q<D_QJ
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(query); ^?(#%~NS
} }PBL
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publicList find(finalString query, finalObject ({C[RsY=6
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parameter){ !lFNG:&`
return getHibernateTemplate().find `i(b%$|^&Z
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(query, parameter); B=n90XO |
} j #:
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public PaginationSupport findPageByCriteria ge?or]T1S
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(final DetachedCriteria detachedCriteria){ Z?=o(hkd
return findPageByCriteria =8tK]lb
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); $MQ<QP
} /{[<J<(8
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public PaginationSupport findPageByCriteria '/\*l<
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(final DetachedCriteria detachedCriteria, finalint oxeu%wj_
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i;
startIndex){ /Ta-3Eh!
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 2SlL`hN>Z
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startIndex); l(_|CkcZ
} %{ rb,6
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public PaginationSupport findPageByCriteria 5RWqHPw+
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(final DetachedCriteria detachedCriteria, finalint fB7Jx6
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pageSize, VO {z)_
finalint startIndex){ oGI'a:iff
return(PaginationSupport) z^tzP~nI
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getHibernateTemplate().execute(new HibernateCallback(){ P`Now7!
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publicObject doInHibernate D4hT Hh
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(Session session)throws HibernateException { | Z7j
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Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); JM/\n4ea:
int totalCount = &0bq3JGW
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((Integer) criteria.setProjection(Projections.rowCount rX5"p!z
}vY^eOK.
()).uniqueResult()).intValue(); YCb|eS^u
criteria.setProjection =Gzs+6A8
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(null);
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List items = ZD|F"v.
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criteria.setFirstResult(startIndex).setMaxResults l8+)Xk>
*$DD+]2
(pageSize).list(); hPz=Ec<zW
PaginationSupport ps = jz=V*p}6
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new PaginationSupport(items, totalCount, pageSize, pnp8`\cIH
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startIndex); f2o6GC_
return ps; Y7qQ`|
} lo6upirZX
}, true); GKF!GbGR@
} 4 Cd5-I
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public List findAllByCriteria(final mM?,e7Xhs
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DetachedCriteria detachedCriteria){ @oH\r-jsgu
return(List) getHibernateTemplate .XeZjoJ$z
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().execute(new HibernateCallback(){ I Ij:3HP
publicObject doInHibernate :XAyMK7
,ZY\})`p
(Session session)throws HibernateException { w<h8`K`3
Criteria criteria = LfW:G5@-
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detachedCriteria.getExecutableCriteria(session); b~ *iL!<
return criteria.list(); $ `\qY ^.(
} :a2[d1
}, true); s.;'-oA
} kxEq_FX
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public int getCountByCriteria(final ^q& Rl\
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DetachedCriteria detachedCriteria){ H$^9#{
Integer count = (Integer) #l-zY}&
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getHibernateTemplate().execute(new HibernateCallback(){ ZRw^<
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publicObject doInHibernate kRwY#
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(Session session)throws HibernateException { dZ*&3.#D5
Criteria criteria = Y$Rte.?
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detachedCriteria.getExecutableCriteria(session); q^^R|X1
return m;xa}b{(i
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criteria.setProjection(Projections.rowCount h\Y~sm?!`
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()).uniqueResult(); V(LfFO{^>?
} ZR|s]'
}, true); :?z@T[-
return count.intValue(); u-jc8W`Zd
} j p~Tlomp
} Syl 9j]
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用户在web层构造查询条件detachedCriteria,和可选的 N|@tP:j
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nI(w7qhub
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PaginationSupport的实例ps。 >Q"3dw
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ps.getItems()得到已分页好的结果集 =I&BO[d
ps.getIndexes()得到分页索引的数组 A/lznBHR
ps.getTotalCount()得到总结果数 _*sd#
ps.getStartIndex()当前分页索引 n[i:$! ,
ps.getNextIndex()下一页索引 [GK##z'5
ps.getPreviousIndex()上一页索引 ,d.5K*?aI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?=_w5D.3J
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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 @_c&lToj_
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一下代码重构了。 &F[N$6:v
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我把原本我的做法也提供出来供大家讨论吧: xi,fm
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首先,为了实现分页查询,我封装了一个Page类: ?l
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java代码:
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/*Created on 2005-4-14*/ U_Mag(^-
package org.flyware.util.page; -<T>paE9
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/** } 21!b :a
* @author Joa cL#zE
* OQg}E@LZ
*/ 4 s9^%K\8{
publicclass Page { Edcv>}PfE
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/** imply if the page has previous page */ T(cpU,Q
privateboolean hasPrePage; ,PKUgL}w
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/** imply if the page has next page */ <+%y
privateboolean hasNextPage; 1`Bhis9X8
}+u<w{-7/
/** the number of every page */ ,ag*
/
privateint everyPage; R Eo{E
{ VM^K1
/** the total page number */ C\bJ_vl;'
privateint totalPage; mB
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/** the number of current page */ ,]9p&xu
privateint currentPage; 4/S3hH
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/** the begin index of the records by the current pA@R,O>zr
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query */ g*4^HbVxt
privateint beginIndex; _IxYnm`pc
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/** The default constructor */ 8yZs>Og?
public Page(){ rJ6N'vw>
!{g>g%2!
} @qA11C.hq
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/** construct the page by everyPage pd.pY*B<[
* @param everyPage tgeXX1Eq!
* */ t""Y -M
public Page(int everyPage){ Nh4&3"g|
this.everyPage = everyPage; CzDg?w b
} &RHx8zScP
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/** The whole constructor */ )U}`x }:,
public Page(boolean hasPrePage, boolean hasNextPage, <]`|HJoy
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int everyPage, int totalPage, k&u5`F
int currentPage, int beginIndex){ k$7Kz"
this.hasPrePage = hasPrePage; JRtDjZ4>
this.hasNextPage = hasNextPage; \y7\RV>>3b
this.everyPage = everyPage; Oo>Uu{{
this.totalPage = totalPage; Jep/%cT$w
this.currentPage = currentPage; f/,8sGkX;
this.beginIndex = beginIndex; qyY/:&E, Z
} n2'XWbMaL
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/** kp)1s>c
* @return [4PiQyr
* Returns the beginIndex. q((%sWp
*/ !(j<Y0xo:
publicint getBeginIndex(){ =C^4nP-
return beginIndex; P}!pmg6V
} /(}YjeS
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/** -Ji uq
* @param beginIndex PL3oV<\4s>
* The beginIndex to set. 1n>AN.nI
*/ |B\76Nk
publicvoid setBeginIndex(int beginIndex){ {q);1Nnf
this.beginIndex = beginIndex; W{]r_`=:6S
} m='_O+ $
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/** QT(]S>--n
* @return MBol_#H
* Returns the currentPage. Fj&8wZ)v)
*/ [bBPs&7u
publicint getCurrentPage(){ ?,eq86-M
return currentPage; [F,s=,S'M
} `cRRdD:dA
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/** ;s$
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* @param currentPage ECuNkmUI
* The currentPage to set. *E/CNMn=E
*/ EPEn"{;U
publicvoid setCurrentPage(int currentPage){ I$fm"N
this.currentPage = currentPage; =u5( zaBe
} R]S!PSoL
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/** S^5Qhv
* @return M(Yt9}Z%Y
* Returns the everyPage. vH"^a/95|
*/ nc#} \
publicint getEveryPage(){ M&rbXi.
return everyPage; lBG"COu
} CG!9{&F
xl(R|D))
/** gI+dyoh
* @param everyPage !qs3fe<uh"
* The everyPage to set. 1#vi]CX
*/ !~}@Eoii4
publicvoid setEveryPage(int everyPage){ r{Z4ifSl(
this.everyPage = everyPage; mr XmM<
} i%r+/D)KvG
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/** L5]uT`Twa
* @return qI2&a$Zb$
* Returns the hasNextPage. WG5)-;>q|
*/ )6U^!95
publicboolean getHasNextPage(){ Xc
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return hasNextPage; R)]+>M-.
} e1R<+`]
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/** o-<.8Z}>at
* @param hasNextPage :CXm@yF~4=
* The hasNextPage to set. f(c#1AJE53
*/ TJ0;xn6o
publicvoid setHasNextPage(boolean hasNextPage){ >ZnnGX6$(
this.hasNextPage = hasNextPage; N >];xb>
} qoC<qn{.a
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/** FBA th
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* @return *XG.?%x*|
* Returns the hasPrePage.
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*/ kcl Z+E
publicboolean getHasPrePage(){ iGIry^D
return hasPrePage; Rw`64 L_
} wG&rkg";#
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/** `_pVwa<@w
* @param hasPrePage ]/?$DNjCc
* The hasPrePage to set. xL!@$;J
*/ 7$JE+gL/7
publicvoid setHasPrePage(boolean hasPrePage){ {$_Gjv
this.hasPrePage = hasPrePage; .oe\wJ S6
} 2<uBC
8qv>C)~~`
/** xyi4U(;
* @return Returns the totalPage. /}3I:aJwb
* h&EF)~G
*/ h"ATRr^
publicint getTotalPage(){ )1Z
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return totalPage; Vx=tP.BO]
} !/EN
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/** fa(- &;q
* @param totalPage nm@.]
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* The totalPage to set. j
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*/ -)!;45
publicvoid setTotalPage(int totalPage){ 3\a VZx!
this.totalPage = totalPage; Qs8Rb ]%|
} b'(Hwc\ t
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} 2;ac&j1
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 bMN]co
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个PageUtil,负责对Page对象进行构造: ~Z$Ro/;l
java代码: E.^F:$2
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/*Created on 2005-4-14*/ L=kETJ:g
package org.flyware.util.page; $`"$ZI6[
)$QZ",&5
import org.apache.commons.logging.Log; NxN~"bfh
import org.apache.commons.logging.LogFactory; Z"
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/** 'F Cmbry
* @author Joa 6@=ipPCR
* *30T$_PiX|
*/ li%A?_/m<&
publicclass PageUtil { D<Z]kR(
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privatestaticfinal Log logger = LogFactory.getLog s#)0- Zj
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(PageUtil.class); uB+:sX-L
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/** NnO%D^P]
* Use the origin page to create a new page u~1 ,88&U
* @param page .N Z
* @param totalRecords GBGna3
* @return r5PZ=+F
*/ x{$/|_
publicstatic Page createPage(Page page, int ffem7eQ
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totalRecords){ *4[P$k$7
return createPage(page.getEveryPage(), a- 7RJ.
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page.getCurrentPage(), totalRecords); <O~ieJim
} saVX2j6Y
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/** g ~>nT>6
* the basic page utils not including exception P+Sgbtc
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handler w,;ox2
* @param everyPage $qM&iI-l0
* @param currentPage OA&r8WK3
* @param totalRecords
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* @return page !.w|+-JKO
*/ =wFl(Q6J
publicstatic Page createPage(int everyPage, int #[sJKW
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currentPage, int totalRecords){ "Q;Vy t
everyPage = getEveryPage(everyPage); e@g=wN"@
currentPage = getCurrentPage(currentPage); !+n'0{
int beginIndex = getBeginIndex(everyPage, >,c'Z<TM
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currentPage); -hZw.eChQa
int totalPage = getTotalPage(everyPage, ]t_ Wl1*|
vW5>{
totalRecords); "VA'W/yv!
boolean hasNextPage = hasNextPage(currentPage, 5YQJNP
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totalPage); @ [j%V ynf
boolean hasPrePage = hasPrePage(currentPage); C0H@
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returnnew Page(hasPrePage, hasNextPage, qex::Qf
everyPage, totalPage, +Q+!#
currentPage, c"NGE
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beginIndex); %Wt F\p
} x=V3_HI/}
>*]B4Q
privatestaticint getEveryPage(int everyPage){ ,-1d2y
return everyPage == 0 ? 10 : everyPage; M0woJt[&
} _`xhP-,`S
s~g]`/h$r
privatestaticint getCurrentPage(int currentPage){ UDHMNubB
return currentPage == 0 ? 1 : currentPage; #kAk
d-QY6
} ?)e6:T(
'o1lJ?~kH
privatestaticint getBeginIndex(int everyPage, int z"V`8D
d@
tD0s
currentPage){ 1c:/c|shQ_
return(currentPage - 1) * everyPage; /B5rWJ2AS
} |i- S}M
1N +ju"2R
privatestaticint getTotalPage(int everyPage, int fP{IW`t}]
bl4I4RB
totalRecords){ $A>]lLo0
int totalPage = 0; K(_8oB784
k(_^Lq f-
if(totalRecords % everyPage == 0) }XRRM:B|)(
totalPage = totalRecords / everyPage; B'D~Q
else 0B(Y{*QB
totalPage = totalRecords / everyPage + 1 ; CZ,2Rq
Dos';9Uq
return totalPage; ^fti<Lw5
} hIwqSKq9
n/+G^:~_
privatestaticboolean hasPrePage(int currentPage){ LEY k
return currentPage == 1 ? false : true; k<%y+v
} (^^}Ke{J
TR!7@Mu3
privatestaticboolean hasNextPage(int currentPage, v8K4u)
X9#i!_*
int totalPage){ *%2,=
p
return currentPage == totalPage || totalPage == ?P Mi#H
3q`Uq`t4mR
0 ? false : true; 57:27d0y
} T$tO[QR/
*TYOsD**9
1#nY Z%
} l!%V&HJV
Ol*|J
=${ImMwj
#
0/,teJk
6R!AIOD>
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 MG74,D.f
T@Th?
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 BU=Ta$#BZ
u$+nl~p[&
做法如下: 5hp)Z7
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 JiRfLB
1yjP`N
的信息,和一个结果集List: DK(8Ml:k
java代码: Ikgia:/-Z
i/F].Sag
(2r808^2
/*Created on 2005-6-13*/ 3s Mmg`
package com.adt.bo; \n0MqXs#
%?!TqJT?{
import java.util.List; Z+Ppd=||,
qz|xow/ns@
import org.flyware.util.page.Page; A7TV-eWG
%(g!,!l)
/** zCSLV>.F
* @author Joa @;>Xy!G
*/ gdG#;T'
publicclass Result { 2yA+zJ
46B
8<Ex`
private Page page; N-}|!pqb
Q=#!wWVP
private List content; jQpG7H
z=DK(b;$z
/** M.KXDD#O
* The default constructor Ir3|PehB
*/ \,yg@R
public Result(){ 9a{9|p>L
super(); >`+lEob
} Xh`Oin}<
6('xIE(R
/** l7uEUMV
* The constructor using fields yeN(_t2.
* #,rP1#?
* @param page K=!?gd!Vw
* @param content !&Us^Q^
*/ \D}$foHg
public Result(Page page, List content){ 4
zipgw
this.page = page; n2&M?MGX
this.content = content;
A}n7A
} ?f=7F
%
c_syJ<
/** ~JohcU}d
* @return Returns the content. Fzn#>`qG
*/ _)^`+{N<
publicList getContent(){ ;e\K8*o
return content; IYB;X
} }r:8w*47
~D!Y]
SK
/** K?,`gCN}v
* @return Returns the page. Hv|(V3-
*/ {fu[&@XV
public Page getPage(){ *jo1?
return page; )iCg,?SSw=
} a}7P:e*u
r8[Ywn<u
/** eHH9#Vrhc$
* @param content 3E:+DF-Z\
* The content to set. WvWZzlw
*/ a,\GOy(q{
public void setContent(List content){ +(vL~
this.content = content; KPI[{T\`ZM
} B \>W
^j]"5@f
/** `-<m#HF:)d
* @param page Bt"*a=t;
* The page to set.
3vF-SgCV
*/ "
{Nw K
publicvoid setPage(Page page){ =N{-lyr)
this.page = page; "gq_^&
} L&qY709
} T2i\S9X
[`=:uUf3
2%t!3F:
;%xG bg!lg
e}q!m(K]e-
2. 编写业务逻辑接口,并实现它(UserManager, Zz56=ZX*_
0p!N'7N
UserManagerImpl)
`;#I_R_K
java代码: kl9<l*
1Yy*G-7}
dF0:'y
/*Created on 2005-7-15*/ f`_6X~
p
package com.adt.service; ]\oE}7K%r
"aeKrMgc6V
import net.sf.hibernate.HibernateException; mS >I#?
[NguQ]B.
import org.flyware.util.page.Page; <N\#6m
/lN09j
import com.adt.bo.Result; EO\@#",a
vKNxL^x
/** Rj{D#5
* @author Joa `jH 0FJQ
*/ CiC@Z,ud`
publicinterface UserManager { ,v*<yz/
ED
R*1!d
public Result listUser(Page page)throws d)jX%Z$LC
o$bD?Zn
HibernateException; 8:4`q9
h_ J|uu
} j=TGe
XX'Rv]T
cLCzLNyKl
*saO~.-;4
D`r_ Dz
java代码: {t&+abY
p&,2@(Q
3W}xYYs]^
/*Created on 2005-7-15*/ z}*74lhF
package com.adt.service.impl; ;/<J.
v0S7 ]?_
import java.util.List; ShRkL<
U0%m*i
import net.sf.hibernate.HibernateException; + Ek('KOF
vt-53fa|
import org.flyware.util.page.Page; b-,]21
import org.flyware.util.page.PageUtil; F6\r"63
'aW<C>
import com.adt.bo.Result; E>6:59+
import com.adt.dao.UserDAO; }9ZcO\M
import com.adt.exception.ObjectNotFoundException; 5T;,wQ<
import com.adt.service.UserManager; cE0Kvqe`
Ok2>%e
/** >QM$
NIf@
* @author Joa wXxk+DV@
*/ ~",,&>#[K
publicclass UserManagerImpl implements UserManager { )t$|'c}
dsJHhsu6
private UserDAO userDAO; k!6wVJ|_Y
nFfwVqV
/** rC!~4xj-
* @param userDAO The userDAO to set. Q!dNJQpb
*/ "Hw%@
publicvoid setUserDAO(UserDAO userDAO){ Bn_@R`
this.userDAO = userDAO; _jCjq
} +A,t9 3:k
SH5G
/* (non-Javadoc) gKGM|0u|r
* @see com.adt.service.UserManager#listUser A1,- qv1s
#.n%$r
(org.flyware.util.page.Page) <xeo9'k6&
*/ y*5bF0
public Result listUser(Page page)throws Gd5J<K
Q.G6y,KR
HibernateException, ObjectNotFoundException { u2 xb ^vu
int totalRecords = userDAO.getUserCount(); _ s[v:c
if(totalRecords == 0) zn|/h,.
throw new ObjectNotFoundException @}cZxFQ!C
`Dco!ih
("userNotExist"); kf<5`8
page = PageUtil.createPage(page, totalRecords); *FT )`
List users = userDAO.getUserByPage(page); bqDHLoB\1
returnnew Result(page, users); Hc{0O7
} qSWnv`hL
pZ4]oK\*
} P$= Y 5
U3yIONlt
/n SmGAO
gnp\z/'>
4X &\/X
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~y(-j[
z2QZ;ZjvRS
询,接下来编写UserDAO的代码: Ya)s_Zr7
3. UserDAO 和 UserDAOImpl: a jCx"J
java代码: ^#4?v^QNh
?#LbhO*
g qRwN p
/*Created on 2005-7-15*/ DEw_dOJ(
package com.adt.dao; kt; |
$
R)w|bpW
import java.util.List; B^SD5
V3u[{^^f
import org.flyware.util.page.Page; 6DG:imGl
'B>%5'SdD
import net.sf.hibernate.HibernateException; p ft6
@'q
|[VtYV _{
/** hd2 X/"
* @author Joa N}3$1=@Y
*/ 6h|@Bz/A
publicinterface UserDAO extends BaseDAO { |&t 2jD(
ui:
publicList getUserByName(String name)throws \&p MF
oiq7I@Y`x
HibernateException; j:9kJq>mv
< g<Lf[n$
publicint getUserCount()throws HibernateException; 0}UJP
_/_1:ivY8
publicList getUserByPage(Page page)throws ;$y(Tvd;
ec4jiE
HibernateException; 7lvUIc?krW
l ^*GqP5
} /IS
j0"/$
KGclo-,
Uk02VuS
jy] hP?QG
o[bG(qHZ
java代码: wr=h=vXU[
zOpl#%"
L$GhM!c
/*Created on 2005-7-15*/ Fs_umy#
package com.adt.dao.impl; oOhm`7iy
~R]E=/ m|
import java.util.List; DG x9 \8^
kN4nRW9z
import org.flyware.util.page.Page; n7"e 79
7RmL#f`
import net.sf.hibernate.HibernateException; av( d0E}}b
import net.sf.hibernate.Query; D@yg)$;z
yWACIaj
import com.adt.dao.UserDAO; H V`{YuP
gOI#$-L
/** *=1;HN3
* @author Joa &t+
*/ \guZc}V]:\
public class UserDAOImpl extends BaseDAOHibernateImpl .[hQ#3)W
%:n1S]Vr
implements UserDAO { 6rEt!v #K[
{6v|d{V+e
/* (non-Javadoc) /vl]Oa&U
* @see com.adt.dao.UserDAO#getUserByName !<!sB)
nu] k<^I5|
(java.lang.String) ={?} [E
*/ O /wl";-
publicList getUserByName(String name)throws I72UkmK`
Z1FO.[FV
HibernateException { zi23k=
String querySentence = "FROM user in class M#J OX/
5r<%xanXW/
com.adt.po.User WHERE user.name=:name"; "-y\F}TE
Query query = getSession().createQuery Sq&*K9:z
H(ht{.sjI
(querySentence); cWl)ZE<hM
query.setParameter("name", name); (XJehdB0
return query.list(); I?v)>||Q
} 0Ng6Xg(QHc
Bo?uwi
/* (non-Javadoc) CJ_X:Frj)
* @see com.adt.dao.UserDAO#getUserCount() ~4[2{M.0>@
*/ X6~y+R
publicint getUserCount()throws HibernateException { mD:d,,~
int count = 0; :4h4vp<
String querySentence = "SELECT count(*) FROM R0;c'W)
Wxg,y{(`
user in class com.adt.po.User"; Eo\#*Cv*
Query query = getSession().createQuery xDu11W+g
f)q\RJA)X
(querySentence); ^Ois]#py
count = ((Integer)query.iterate().next EH"iK2n\9
pvTV*
()).intValue(); (|Am
return count; }$V]00
X
} 5j`"@C5;O
Phl't~k
/* (non-Javadoc) k0?4vA
* @see com.adt.dao.UserDAO#getUserByPage _Kx
/z
S(5.y%"<
(org.flyware.util.page.Page) 0/<}.Z]
*/ [kzcsJ'/e
publicList getUserByPage(Page page)throws $nQ; ++
StWDNAf)
HibernateException { %4 cUa| =?
String querySentence = "FROM user in class 3O<<XXar
{o7ibw=E)
com.adt.po.User"; h[3N/yP
Query query = getSession().createQuery c6s*u%+},
"uCx.Q9ef
(querySentence); +DM+@F
query.setFirstResult(page.getBeginIndex()) B_M)<Ad
.setMaxResults(page.getEveryPage()); .G1NY1\
return query.list(); $Vbgfp~U-
} 673v
_%!C;`3Y
} Y>EwU
q|om^:n.
~R/7J{Sg
gE JmMh
m:/@DZ
至此,一个完整的分页程序完成。前台的只需要调用 %p"x|e
'/SMqmi
userManager.listUser(page)即可得到一个Page对象和结果集对象 SxC$EQgL
$I-$X?
的综合体,而传入的参数page对象则可以由前台传入,如果用 N7%Jy?-+
bXc7$5(!VB
webwork,甚至可以直接在配置文件中指定。 @g[p>t> *
&529.>
下面给出一个webwork调用示例: *-Y77p7u
java代码: WDKj)f9cy
e}f!zA
eg)=^b
/*Created on 2005-6-17*/ }_0?S0<#
package com.adt.action.user; 9M~EH?>+[
sU4(ed\gI\
import java.util.List; p{!aRB%
-hL8z$}
import org.apache.commons.logging.Log; 5|xFY/%
import org.apache.commons.logging.LogFactory; G-Z_pGer^
import org.flyware.util.page.Page; 1QE-[|
'/b,3:
import com.adt.bo.Result; dnNC
=
siY
import com.adt.service.UserService; d#I'9O0&
import com.opensymphony.xwork.Action;
k$}XZ,Q
zrU0YHmt
/** kJ>l,AD/
* @author Joa X6!u(plVQ
*/ CBs0>M/
publicclass ListUser implementsAction{ }k
duN0
C>N)~Ut
privatestaticfinal Log logger = LogFactory.getLog 9fvy)kX;s
;38DB o
(ListUser.class); sqei(OXy
nWbe=z&y8[
private UserService userService; ~m[^|w
W$B>O
private Page page;
v%/_*69a
]&yO>\MgJB
privateList users; Mmbb}(<
SYB
}
e
/* %#02Z%?%
* (non-Javadoc) bU=!~W5
* WUGPi'x
* @see com.opensymphony.xwork.Action#execute() 0fXdE ;M3
*/ kE,~NG9P
publicString execute()throwsException{ qUx!-DMY
Result result = userService.listUser(page); ep3_G\m
page = result.getPage(); N|z-s
users = result.getContent(); joAR;J
return SUCCESS; wz9V)_V*
} sJ7r9O`x
YQ4;X8I`r
/** Bca\grA
* @return Returns the page. 9,82Uta
*/ ??aOr*%
public Page getPage(){ <QugV3e
return page; !a~>;+
} MT$OjH'Q`
^]Lr_k
/** mNKe,H0
* @return Returns the users. p44d&9
*/ 6fY(u7m|p
publicList getUsers(){ n+rAbn5o$
return users; g*b%
} %$Wt"~WE"O
EfcoJgX
/** ^;<s"TJ(m)
* @param page ZBdZr
* The page to set. cA`R~o"
*/ R5r )01
publicvoid setPage(Page page){ >UE_FC*u
this.page = page; EW0H"YIC
} `{N0+n
ZJ 8~f
/** W.-[ceM
* @param users X"y rA;,o
* The users to set. ,@khV
*/ ]3NH[&+
publicvoid setUsers(List users){ +yVz)
X
this.users = users; (JocnM|U
} VDx=Tsu-
nDkyo>t.
/** %QVX1\>]
* @param userService )j4]Y dJ
* The userService to set. z62e4U][
*/ 8QE0J$d5
publicvoid setUserService(UserService userService){ k5$_Q#
this.userService = userService; }7IS:"tu
} SM@l4GH
} YCj"^RC^
37v!:xF!
QSW03/_f
f%an<>j^w
,`^B!U3m
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 9 @!Og(l
c`#E#
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 c;&m}ImLe.
bDeHU$
么只需要: w[uK3A v
java代码: T6Z 2 #
q^JJ5{36e
@r%[e1.
<?xml version="1.0"?> >O&(G0!N+}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^Gq4Yr
(WVN*OR?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- TF}<,aR
hWJ\dwF
1.0.dtd"> !?DPI)
U8c0N<j
<xwork> 2L[/.|
/j0<x^m/
<package name="user" extends="webwork- 1/jJ;}
X)e6Y{vO
interceptors"> g:dw%h
jF<Y,(C\
<!-- The default interceptor stack name !l?Go<^*L
.</d$FM JE
--> we4e>)
<default-interceptor-ref Tsxl4ZK
azr|Fz/
name="myDefaultWebStack"/> lE78Yl]
x>A(016:C
<action name="listUser" /1zi(z
\L}Soe'
class="com.adt.action.user.ListUser"> f>s3Q\+
<param k:Da+w_'1
t.t$6+"5We
name="page.everyPage">10</param> |g;hXr#~
<result ?SK1*; i
!>TVDN>
name="success">/user/user_list.jsp</result> jX-v9eaA
</action> M`-#6,m3
X~*1
</package> u>
XCE|D*
+7U$qEG
</xwork> Yz us=
?[hIv6c
yd$_XWp?\
KS!mzq-
!X$e;V"HX
|>5NH'agV
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 )'?3%$EM
iOkRB[hi
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。 e%uPZ >'q
3lcd:=
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Z
`sM(?m
\hai
8~YhT]R=
^q-]."W]t~
q(p]6Ha|
我写的一个用于分页的类,用了泛型了,hoho H5'/i;
'h53:?~
java代码: z|^:1ov,
bX6eNk-L
2 DJs'"8
package com.intokr.util; 7m~.V[l1
\XFF(
import java.util.List; +)k%jIi!
=e=sK'NvD
/** 3.Z}2F]
* 用于分页的类<br> @d:TAwOI'
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #!wu}nDu
* VI:
!#
* @version 0.01 .aV#W@iyK
* @author cheng H:Y?(" k
*/ @W[`^jfQ
public class Paginator<E> { f]W$4f{
privateint count = 0; // 总记录数 %ZF47P%6
privateint p = 1; // 页编号 kG@~;*;l
privateint num = 20; // 每页的记录数 9dn~nnd'n
privateList<E> results = null; // 结果 Jz(wXp
btoye \rl
/** JnQ5r>!>3
* 结果总数 _LU]5$\b
*/ =&jLwy
publicint getCount(){ }K1v=k
return count; ad+@2-Y
} P /|2s
J5e
publicvoid setCount(int count){ '=C)Hj[D
this.count = count; c}v>Mx
} ZFpi'u.&
)65 o
/** <Dojl
#
* 本结果所在的页码,从1开始 P>n}\"z4
* C +S
* @return Returns the pageNo. FC[8kq>Hk
*/ `1k0wT(
publicint getP(){ ,7-@eZ
return p; r#hA kOw
} OZ##x
,'w9@A
/** ncZ5r0
* if(p<=0) p=1 Q{-T;T
* *gF8"0s
* @param p O(q1R#n-}+
*/ i
E p{
publicvoid setP(int p){ uvC ![j^~
if(p <= 0) 9jW/"
p = 1; M9so3L<N0
this.p = p; $fZVh%
} w6FtDl$
P(AcDG6K
/** |rW,:&;
* 每页记录数量 n1n->l*HGP
*/ s\&qvL1D
publicint getNum(){ }\Kki
return num; <4UF/G)
} H{qQ8j)
W
Cz+
/** ip.aM#
* if(num<1) num=1 ${ fJ]
*/ Tk1U
publicvoid setNum(int num){ 'PiQ|Nnb|
if(num < 1) bDK%vx!_
num = 1; 4'EC(NR7N
this.num = num; kq+`.
} 2smQD8t
k6.<