Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n!p<A.O7@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?HF%(>M
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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 h3LE>}6D
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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 S4=~`$eP
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分页支持类: I!e} )Y
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java代码: wiz$fj
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package com.javaeye.common.util; QFYWA1<pDh
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import java.util.List; O+y-}7YX
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publicclass PaginationSupport { &boOtl^
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publicfinalstaticint PAGESIZE = 30; rM'=_nmi
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privateint pageSize = PAGESIZE; 0TQ$C-%
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privateList items; cSXwYZDx?
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privateint totalCount; MyT q
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privateint[] indexes = newint[0]; bbrXgQ`s+w
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privateint startIndex = 0; 9 FB19
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public PaginationSupport(List items, int u(fm@+$^
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totalCount){ 0aG ni|
setPageSize(PAGESIZE); rg^'S1x|
setTotalCount(totalCount); e" St_z(
setItems(items); j'A_'g'^
setStartIndex(0); dBz/7&Q
} 7=;R& mqC
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public PaginationSupport(List items, int :]\([Q+a
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totalCount, int startIndex){ Vh_P/C+
setPageSize(PAGESIZE); i\,-oO
setTotalCount(totalCount); 3j\1S1
setItems(items); ,P;Pm68V
setStartIndex(startIndex); B} lvr-c#
} u6AA4(
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public PaginationSupport(List items, int ~ _/(t'9
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totalCount, int pageSize, int startIndex){ 7pe\M/kl
setPageSize(pageSize);
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setTotalCount(totalCount); #ZB~x6i6
setItems(items); Yt;MV)
setStartIndex(startIndex); <sBbT`
} ML|FQ
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publicList getItems(){ RZXjgddL
return items; \G*0"%!U
} Y$"O
VC
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publicvoid setItems(List items){ U~:-roQ(\
this.items = items; Dfmjw
} hb}+A=A=+
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publicint getPageSize(){ 5>[u `
return pageSize; ?8'*,bK
} ~"nxE
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publicvoid setPageSize(int pageSize){ <3LbNFP
this.pageSize = pageSize; 3 2&;`]C
} M/b Sud?@%
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publicint getTotalCount(){ ~E17L]ete
return totalCount; 3LOdj T
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} e"|efE
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publicvoid setTotalCount(int totalCount){ VK m&iidU
if(totalCount > 0){ '=b/6@&
this.totalCount = totalCount; {*G9|#[/@
int count = totalCount / qLD
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pageSize; *\
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if(totalCount % pageSize > 0) X%
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count++; IG2r#N|C#
indexes = newint[count]; F3On?x)
for(int i = 0; i < count; i++){ Te"ioU?.
indexes = pageSize * k\5c|Wq|g
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i; Hj^1or3R]
} :D~D U,e'
}else{ -t!~%_WCv
this.totalCount = 0; 'jWr<]3
} rNXQf'*I
} d;boIP`M;
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publicint[] getIndexes(){ ztcp/1jIvS
return indexes; j eoz*Dz
} (C\]-E>
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publicvoid setIndexes(int[] indexes){ I|qo+u)
this.indexes = indexes; )_HA>o_?C:
} p`olCp'
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publicint getStartIndex(){ u^^[Q2LDU}
return startIndex; 6'k<+IR
} bRFLcM
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publicvoid setStartIndex(int startIndex){ XP!S$Q]D
if(totalCount <= 0) mE+*)gb:Rd
this.startIndex = 0; ~Y^+M*
elseif(startIndex >= totalCount) (KjoSN(
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this.startIndex = indexes +}Dw3;W}m
\ 2M_\Q`NY
[indexes.length - 1]; rBQ _iB_
elseif(startIndex < 0) !|S(Ms
this.startIndex = 0; L+b6!2O,
else{ b/+u4'"
this.startIndex = indexes V(H1q`ao9
|3('
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[startIndex / pageSize]; R`NYEptJ
} ?+))}J5N\
} |mZxfI
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publicint getNextIndex(){ Z9v31)q(
int nextIndex = getStartIndex() + u|\1hLXX
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pageSize; /CrSu
if(nextIndex >= totalCount) rDdoOb]B
return getStartIndex(); (p" %O
else W: z6Koc0
return nextIndex; .73X3`P25
} 8SMxw~9$
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publicint getPreviousIndex(){ tH!]Z4}u
int previousIndex = getStartIndex() - g@d*\ P)
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pageSize; k
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if(previousIndex < 0) g_;\iqxL
return0; NDN7[7E
else /p/]t,-j2
return previousIndex; _P!m%34|
} tR#OjkvX
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} $zUP?Gq!
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抽象业务类
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java代码: 'lH|eU&-
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/** 4VHn \
* Created on 2005-7-12 )~X2
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*/ y#`tgJ:
package com.javaeye.common.business; ,<.V7(|t)
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import java.io.Serializable;
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import java.util.List; R7%#U`Q^A
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import org.hibernate.Criteria; \<bx[,?
import org.hibernate.HibernateException; n3WlZ!$
import org.hibernate.Session; oe^ I
import org.hibernate.criterion.DetachedCriteria; G0Iw-vf
import org.hibernate.criterion.Projections; 6 W/`07'
import rm7ANMB:
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org.springframework.orm.hibernate3.HibernateCallback; h0EEpL|\
import 6%' QjwM_
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org.springframework.orm.hibernate3.support.HibernateDaoS "69s)~
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upport; KS+'|q<?w
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import com.javaeye.common.util.PaginationSupport; !t"4!3
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public abstract class AbstractManager extends & l<.X
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HibernateDaoSupport { aj='b.2)
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privateboolean cacheQueries = false; ,~U>'&M;
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privateString queryCacheRegion; 1er
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publicvoid setCacheQueries(boolean KYm0@O>;
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cacheQueries){ $c!p&
this.cacheQueries = cacheQueries; A`%k:@
} b!t0w{^w
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publicvoid setQueryCacheRegion(String f_OQ./`
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queryCacheRegion){ G[ PtkPSJ
this.queryCacheRegion = 38B2|x
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queryCacheRegion; =jN.1}
} b=C*W,Q_#
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publicvoid save(finalObject entity){ ZvM(Q=^
getHibernateTemplate().save(entity); yZY \MB/
} qz_7%c]K[
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publicvoid persist(finalObject entity){ 6q\bB
getHibernateTemplate().save(entity); Pm6pv;WK
} K-)]
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publicvoid update(finalObject entity){ ;fTKfa
getHibernateTemplate().update(entity); HQdxL*N%^
} FjHv
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publicvoid delete(finalObject entity){ Y(ykng
getHibernateTemplate().delete(entity); 3DX*gsx(
} ^CYl\.Y@
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publicObject load(finalClass entity, ;+R&}[9,A)
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finalSerializable id){ B3`5O[6
return getHibernateTemplate().load {lzWrUGO
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(entity, id); 6Igz:eX
} ,<_A2t 2
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publicObject get(finalClass entity, !qQl@j O
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finalSerializable id){ |*xA8&/
return getHibernateTemplate().get d'gfQlDny
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(entity, id); NN{?z!
} x;KOqfawv
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publicList findAll(finalClass entity){ Tk[ $5u*,
return getHibernateTemplate().find("from p$c6<'UqH
e)k9dOR
" + entity.getName()); _yx>TE2e
} *KF#'wi
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publicList findByNamedQuery(finalString q9K)Xk$LF
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namedQuery){ r|8d
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return getHibernateTemplate cl3K<'D
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().findByNamedQuery(namedQuery); 3ZPWze6
} sE<V5`Z=
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publicList findByNamedQuery(finalString query, !*&V-4
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finalObject parameter){ 05#1w#i
return getHibernateTemplate PdFKs+Z`
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().findByNamedQuery(query, parameter); 2,oKVm+
} k"%~"9
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publicList findByNamedQuery(finalString query, :pY/-Cgv
*;slV3
finalObject[] parameters){ +o{R _
return getHibernateTemplate >>)b'c
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().findByNamedQuery(query, parameters); Kk0g0C:"EO
} eK=xrk
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publicList find(finalString query){ d"mkL-
return getHibernateTemplate().find .G.0WR/2
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(query); IMFDM."s
} i>A s;*
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publicList find(finalString query, finalObject T*Exs|N2P-
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parameter){ /t57!&
return getHibernateTemplate().find ~H_/zK6e
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(query, parameter); _Ey9G
} VA>35w
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public PaginationSupport findPageByCriteria 2#]#sZmk
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(final DetachedCriteria detachedCriteria){ \ZFGw&yN
return findPageByCriteria KP^V>9q
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @V sG'
} xC:L)7#aw
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public PaginationSupport findPageByCriteria LgU_LcoM*
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(final DetachedCriteria detachedCriteria, finalint [Td4K.c
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startIndex){ {hjhL: pg
return findPageByCriteria ~"H,/m%2o
{SPq$B_VR
(detachedCriteria, PaginationSupport.PAGESIZE, Oc#syfO
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startIndex); l"T44CL;
} %6,SKg p
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public PaginationSupport findPageByCriteria qvsd5P eCO
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(final DetachedCriteria detachedCriteria, finalint P>C~
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pageSize, w~A{(-
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finalint startIndex){ hGe/;@%
return(PaginationSupport) dJoaCf`w
~s*)f.l
getHibernateTemplate().execute(new HibernateCallback(){ X6X
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publicObject doInHibernate )gIKH{JYL
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(Session session)throws HibernateException { Xm}/0g&7
Criteria criteria = jDfC=a])
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detachedCriteria.getExecutableCriteria(session); L|:`^M+^w
int totalCount = nZyX|SPk
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((Integer) criteria.setProjection(Projections.rowCount Y@vTaE^w3
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()).uniqueResult()).intValue(); /QWvW=F2<
criteria.setProjection C*_C;6.~Y
5E;qM|Ns
(null); w^|*m/h|@u
List items = VcO0sa f`
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criteria.setFirstResult(startIndex).setMaxResults EStB#V^
8@Q$'TT6}
(pageSize).list(); mbxZL<ua
PaginationSupport ps = C.yQ=\U2
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new PaginationSupport(items, totalCount, pageSize, b\kdKVh&
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startIndex); f!uw zHA`?
return ps; @[<><uTH
} _Xc8Yg }`
}, true); Y-_`23x`
} R6Km\N
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public List findAllByCriteria(final KNvZm;Q6
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DetachedCriteria detachedCriteria){ y<|7z99L
return(List) getHibernateTemplate O7m(o:t x3
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().execute(new HibernateCallback(){ i{NzV
publicObject doInHibernate -`kW&I0
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(Session session)throws HibernateException { ThajHK|U
Criteria criteria = qZtzO2Mt
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detachedCriteria.getExecutableCriteria(session); v!6
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return criteria.list(); P6-s0]-g
} DS(}<HK{
}, true); l'-Bu(
} s4y73-J^.v
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public int getCountByCriteria(final wx=
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DetachedCriteria detachedCriteria){ *=/ { HvJ
Integer count = (Integer) Cazocq5
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getHibernateTemplate().execute(new HibernateCallback(){ x_N'TjS^{
publicObject doInHibernate x;P_1J%Q
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(Session session)throws HibernateException { _?m(V=z>
Criteria criteria = Eex~xiiV
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detachedCriteria.getExecutableCriteria(session); S]e|"n~@
return z,[Hli*0
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criteria.setProjection(Projections.rowCount QC
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{tuYs:
()).uniqueResult(); .Ni\\
} S"bg9o
}, true); ArI2wM/v
return count.intValue(); ~F|+o}a`
} y1eWpPJa
} l|JE#
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用户在web层构造查询条件detachedCriteria,和可选的 y*jp79G
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h,u,^ r
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PaginationSupport的实例ps。 B[Ku\A6&
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ps.getItems()得到已分页好的结果集 Xv5wJlc!d
ps.getIndexes()得到分页索引的数组 Ct <udO
ps.getTotalCount()得到总结果数 _/s$ZCd
ps.getStartIndex()当前分页索引 *MhRW,=
ps.getNextIndex()下一页索引 z;,u}u}aI
ps.getPreviousIndex()上一页索引 m{Wu"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i4Q@K,$
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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 Uou1mZz/
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一下代码重构了。 mUAi4N
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我把原本我的做法也提供出来供大家讨论吧: T9E+\D
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首先,为了实现分页查询,我封装了一个Page类: Drgv`z
java代码: +<Nn~1
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/*Created on 2005-4-14*/ iJ)_RSFK
package org.flyware.util.page; ojm @t
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/** #K_ii)n
* @author Joa [B*x-R[FI
* HTv2#
*/ @|Cz-J;D
publicclass Page { 8+Lm's=W*
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/** imply if the page has previous page */ +/4A
privateboolean hasPrePage; V# }!-Xj
}1L4"}L.
/** imply if the page has next page */ e }?db
privateboolean hasNextPage; *k7+/bU~~
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/** the number of every page */ D#9m\o_
privateint everyPage; G/y5H;<9M
]!W=^!
/** the total page number */ A_"w^E{P
privateint totalPage; &)#
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/** the number of current page */ #X+JHl
privateint currentPage; T8?Ghbn
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<
/** the begin index of the records by the current <6%?OJhp
e-})6)XgA
query */ GLH0 ]
privateint beginIndex; U#7#aeI
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/** The default constructor */ '|6]_
public Page(){ @(EAq<5{
1SQ3-WUs
} Ljm[?*H#
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/** construct the page by everyPage IkL#SgY
* @param everyPage gMi0FO'
* */ l5Ui w2
public Page(int everyPage){ <`8n^m*
this.everyPage = everyPage; gmUz9P(
} P1.[
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/** The whole constructor */ nmee 'oEw
public Page(boolean hasPrePage, boolean hasNextPage, |"q5sym8Y_
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k&M;,e3v6
int everyPage, int totalPage, {r,.!;mHu
int currentPage, int beginIndex){ ]? c
B:}
this.hasPrePage = hasPrePage; JMCKcZ%N
this.hasNextPage = hasNextPage; ydEoC$?0
this.everyPage = everyPage; xWH.^o,"
this.totalPage = totalPage; ?.m bK
this.currentPage = currentPage; >F|>cc>_E
this.beginIndex = beginIndex; 6$hQ35
} M5LfRBO
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/** LRxZcxmy
* @return i]c!~`
* Returns the beginIndex. h:))@@7MJ
*/ ,hDWPs2S
publicint getBeginIndex(){ 4Co6(
return beginIndex; B6+khuG(
} +zqn<<9
7uqzm
/** A;q9rD,_
* @param beginIndex "m):Y;9iQ?
* The beginIndex to set. ZuzEg *lb
*/ YsC>i`n9
publicvoid setBeginIndex(int beginIndex){ ,C\i^>=
this.beginIndex = beginIndex; Gq)]s'r2
} DaQ?\uq
u= *FI
/** c1(RuP:S
* @return .|KyNBn
* Returns the currentPage. 1/B>XkCJ
*/ U7,e/?a
publicint getCurrentPage(){ G<zwv3
return currentPage; EmWn%eMN
} AG
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vQG5*pR*w
/** |u% )gk
* @param currentPage P-_6wfg,;>
* The currentPage to set. Rxt^v+ ,$
*/ eI}aQ]$ED
publicvoid setCurrentPage(int currentPage){ e-/&$Qq
this.currentPage = currentPage; ](]i 'fE>
} [-1^-bb
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/** $?iLLA~
* @return gT{Q#C2Baw
* Returns the everyPage. x
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*/ Ys9[5@7
publicint getEveryPage(){ T9|m7
return everyPage; 79rD7D&g
} .^33MWu6
aH(J,XY
/** ,Q$q=E;X
* @param everyPage ah$b[\#C
* The everyPage to set. un"Gozmt5
*/ w>&aEv/f
publicvoid setEveryPage(int everyPage){ dh\'<|\K
this.everyPage = everyPage; Xh"n]TK
} =+-UJo5
oAVnK[EMq`
/** wc@X.Q[
* @return e`_LEv
* Returns the hasNextPage. &ee~p&S,>
*/ hp50J
publicboolean getHasNextPage(){ e(;,`L\*
return hasNextPage; z]y.W`i
} ~8Fk(E_
;\dBfP
/** Z9ZPr?C=
* @param hasNextPage +4~_Ei[i
* The hasNextPage to set. ./Zk`-OBT
*/ Lnl(2xD
publicvoid setHasNextPage(boolean hasNextPage){ :K,i\
this.hasNextPage = hasNextPage; T@B/xAq5!
} /N10
k/_ 59@)
/** dh iuI|?@
* @return oG?Xk%7&\
* Returns the hasPrePage. 3BUSv#w{i
*/ 9wUkh}s
publicboolean getHasPrePage(){ <?.&^|kS
return hasPrePage; rl;~pO5R9
} yjX9oxhtL
K&]G3W%V
/** Hyl%mJ
* @param hasPrePage .p3,O6y2(F
* The hasPrePage to set. 3BJ0S.TF
*/ Xza(k
publicvoid setHasPrePage(boolean hasPrePage){ >Eto(
y"q
this.hasPrePage = hasPrePage; K#d`Hyx
} ;(Or`u]Dr
CNyIQ}NJ
/** S!CC
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* @return Returns the totalPage. CAWNDl4
* BoWg0*5xb
*/ (k.[GfCbD
publicint getTotalPage(){ 1N-\j0au
return totalPage; Y\k#*\'Y~
} z'n:@E
b94DJzL1z
/** {$
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* @param totalPage *u [BP@vE
* The totalPage to set. pofie$
*/ U(g:zae
publicvoid setTotalPage(int totalPage){ L|xbR#v
this.totalPage = totalPage; s Y Qk
} {rw|# Z>A
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} ;bib/
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dn+KH+v
s} ;{ZAtE
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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 *Kgks 4
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个PageUtil,负责对Page对象进行构造: }2.`N%[
java代码: /nNN,hz
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/*Created on 2005-4-14*/ Vn}0}Jz
package org.flyware.util.page;
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import org.apache.commons.logging.Log; oW*16>IN9l
import org.apache.commons.logging.LogFactory; 0R'?~`aTt
!)0;&e5
/** d.d/<
* @author Joa Id .nu/
* 6ojo :-%Vf
*/ ?M9=yA
publicclass PageUtil { ChPmX+.i_
v MH
privatestaticfinal Log logger = LogFactory.getLog Ckuh:bs
<uw9DU7G
(PageUtil.class); x2\qXN/R
om z
/** >uhaW@d
* Use the origin page to create a new page K`zdc`/
* @param page m@v\(rT.
* @param totalRecords IK=a*}19L
* @return |&) dh<
*/ YkKi|k
publicstatic Page createPage(Page page, int SsDmoEeB[
c9 _rmz8
totalRecords){ :>f )g
return createPage(page.getEveryPage(), 6}Ci>_i4#
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page.getCurrentPage(), totalRecords); `0gyr(fES
} nT$SfGFj8
WO>nIo5Y
/** D8?Vn"
* the basic page utils not including exception s$`0yGmQ
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0t
handler c]o'xd,T8\
* @param everyPage {]@= ijjf
* @param currentPage YZ8>OwQz2
* @param totalRecords [<yaXQxl
* @return page P{>!5|k
*/ >jLY"
publicstatic Page createPage(int everyPage, int O-hAFKx
@:vwb\azVD
currentPage, int totalRecords){ `kXs;T6&
everyPage = getEveryPage(everyPage); ]Q3ADh
currentPage = getCurrentPage(currentPage); \?k'4rH
int beginIndex = getBeginIndex(everyPage, %XQ(fj>
-zeG1gr3
currentPage); Jk
n>S#SZ
int totalPage = getTotalPage(everyPage, G<J?"oQbRT
AH7}/Rc
totalRecords); wc4{)qDE
boolean hasNextPage = hasNextPage(currentPage, E4/Dr}4
2eY_%Y0
totalPage); bwMm#f
boolean hasPrePage = hasPrePage(currentPage); o|<!"AD7
~HsJUro
returnnew Page(hasPrePage, hasNextPage, N5
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everyPage, totalPage, Z=o2H Bm7
currentPage, 3bH'H*2
}9OC,Y8?D
beginIndex); j6 z^Tt12
} y?? XIsF
x
g
privatestaticint getEveryPage(int everyPage){ vXZOy%$o
return everyPage == 0 ? 10 : everyPage; '_FsvHQ
} f46t9dxp$
PKiy5D*8p
privatestaticint getCurrentPage(int currentPage){ =-n}[Y}A
return currentPage == 0 ? 1 : currentPage; nmKp[-5
} [hv~o~q
eru.m+\
privatestaticint getBeginIndex(int everyPage, int r[iflBP
;[OH(!
currentPage){ i<Zc"v;
return(currentPage - 1) * everyPage; VjZ|$k
} Qpc__dA\
}WXi$(@v
privatestaticint getTotalPage(int everyPage, int 7;wd(8
. 3T3EX|G
totalRecords){ ( ^Nz9{
int totalPage = 0; 5<Nx^D
=m#?neop
if(totalRecords % everyPage == 0) `+:`_4
totalPage = totalRecords / everyPage; &d^m 1
else S;#'M![8
totalPage = totalRecords / everyPage + 1 ; /@TF5]Ri
je=a/Y=%U{
return totalPage; yYA$I'Bm\
} >_ T-u<E
s9DYi~/,
privatestaticboolean hasPrePage(int currentPage){ h
J)h\
return currentPage == 1 ? false : true; y _k
l:Ssa
} #c.K/&Gc7j
E{P|)`,V
privatestaticboolean hasNextPage(int currentPage, g(CI;f}y
Txb#C[`
int totalPage){ |t#)~Oo
return currentPage == totalPage || totalPage == j{+.tIzpq[
[/41%B2
0 ? false : true; /"Uqa,{
} R8Fv{7]c
=MDysb&:
],Do6
@M-
} P{lB50
sWnLEw
;+hH
v;D~Pa
YO}<Ytx
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。 /!XVHkX[
LBDjIpR6
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
HvJs1)Wo&
_
*Pf
做法如下: r0% D58
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *#+An<iT ;
^9:Z7 >Z
的信息,和一个结果集List: _ZSR.w}j/
java代码: wgGl[_)
Y\g3hM
pG;U2wE
/*Created on 2005-6-13*/ 3"~!nn0;
package com.adt.bo; 07{)?1cod4
t&e{_|i#+
import java.util.List; }a(dyr`S
0*{%=M
import org.flyware.util.page.Page; )|#sfHv7
k!'a,R:
/** ,/|T-Ka
* @author Joa m#\dSl}
*/ bq0zxg%
publicclass Result { UH"%N)[
'YSHi\z ](
private Page page; z9Rp`z&`E
3eQ&F~S
private List content; YNsJZnGr8#
$kp{Eg '
/** hZt!/?dc
* The default constructor Bh-ym8D
*/ %:*
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public Result(){ :&."ttf=
super(); tf`^v6m%]
} ds[|
qF;|bF
/** 9V*qQS5<p
* The constructor using fields /hyN;.hpOO
* *VxgARIL
* @param page i?^L/b`H
* @param content =U?dbSf1*
*/ j/?kL{B
public Result(Page page, List content){ X$W~mQma6
this.page = page; fVpMx4&F
this.content = content; u;2[AQ.
} GC}==^1
Wdbed U~`Q
/** .3Oap*X
* @return Returns the content. a<bwzX|.
*/ T1=fNF
publicList getContent(){ Z4
=GMXj
return content; 1o{Mck
} 2`=7_v
_KAQ}G3
/** ^s"R$?;h
* @return Returns the page. ;>7De8v@@
*/ 0YDR1dO(*
public Page getPage(){ w~qT1vCCN
return page; Vs!Nmv`
} .eVG:tl\
t;\Y{`
/** XU(eEnmom
* @param content 4@ai6,<
* The content to set. o0KL5].
*/ ##" HF
public void setContent(List content){ Oxd]y1
this.content = content; ]~3V}z,T*
} -6B4sZpzD
h(EhkCf
/** +T Dw+
* @param page 6qnzBA7
* The page to set. c9h6C
*/ Wvf
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publicvoid setPage(Page page){ C1QA)E['V
this.page = page; 0flRh)[J
} [ v*ju!
} 1yu4emye4
[` 7ThHX
20Wg=p9L
cyz3,3\e
r*Ca}Z
2. 编写业务逻辑接口,并实现它(UserManager, +QJ#2~pE
YNi.SXH
UserManagerImpl) 5$C-9
java代码: T9[Q
Btcy)LRk
+52{-a,>
/*Created on 2005-7-15*/ -nV9:opD
package com.adt.service; I
b5rqU\
E~"y$Fqe
import net.sf.hibernate.HibernateException; o?\?@H
/%io+94
import org.flyware.util.page.Page; C;^X[x%h7$
~Z'?LV<t
import com.adt.bo.Result; fI|Nc
i=2N;sAl
/** R4:b{ )=O
* @author Joa e$rZ5X
*/ },-H"Qs
publicinterface UserManager { Pe3o;mx
X=&KayD
public Result listUser(Page page)throws hp|YE'uYT
I%KYtv~`
HibernateException; /cP"h!P}~~
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} ?4T-@~~*`=
ysY*k` 5
/N.U/MPL_
IJcsmNWm
\qJXF|z<K
java代码: d8P^lv*rQW
|P?*5xPB
AFwdJte9e
/*Created on 2005-7-15*/ uQKT
package com.adt.service.impl; ;
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-aCKRN85
import java.util.List; O?#7N[7
b@hqz!)l`
import net.sf.hibernate.HibernateException; '!B&:X)
Ml-6OvQ7g
import org.flyware.util.page.Page; Ab.(7GFK
import org.flyware.util.page.PageUtil; $/Uq0U
{]4LULq
import com.adt.bo.Result; !R`{ TbN
import com.adt.dao.UserDAO; ~*];pV]A[
import com.adt.exception.ObjectNotFoundException; $6R-5oQ
import com.adt.service.UserManager; 5]:U9ts#
j^RmrOg,
/** NC6&x=!3
* @author Joa H3-hcx54T
*/ (KZ{^X?a
publicclass UserManagerImpl implements UserManager { a/xn'"eli
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private UserDAO userDAO; \1M4Dl5!
_;\_l
/** SNk=b6`9
* @param userDAO The userDAO to set. ysnx3(+|
*/ ('+d.F[109
publicvoid setUserDAO(UserDAO userDAO){ F#5~M<`.o
this.userDAO = userDAO; 5'u<iSmBo
} R[]Mdt<
EQSQFRk;
/* (non-Javadoc) 2&J)dtqz
* @see com.adt.service.UserManager#listUser {Ou1KDy#)
mgU<htMr1
(org.flyware.util.page.Page) 5L}/&^E#p
*/ W=+ Y|R!
public Result listUser(Page page)throws m+z&Q
@d1Q"9}B
HibernateException, ObjectNotFoundException { +k R4E23:
int totalRecords = userDAO.getUserCount(); qwAT>4
if(totalRecords == 0) &m;*<}X
throw new ObjectNotFoundException Bdpy:'fJn
l,aay-E
("userNotExist"); V0 a3<6@4
page = PageUtil.createPage(page, totalRecords); w7&A0M
List users = userDAO.getUserByPage(page); k$:|-_(w
returnnew Result(page, users); t4-[Z$n5
} TIg3`Fon
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} {R{=+2K!|k
_Y m2/3!
v4 E}D
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Bk{]g=DO
vtJJ#8a]
询,接下来编写UserDAO的代码: k4zZ7H
3. UserDAO 和 UserDAOImpl: lPAQ3t!,
java代码: SSzIih@u
,|/f`Pl
X2'0PXv>!
/*Created on 2005-7-15*/ sV*H`N')S
package com.adt.dao; NvX[zqNP_R
E _|<jy$`
import java.util.List; )D%~`,#pQ
@IZnFHN
import org.flyware.util.page.Page; ~pky@O#b
uCB=u[]y4
import net.sf.hibernate.HibernateException; ;722\y(Y
;-Aa|aT!
/** +1!ia]
* @author Joa <wHP2|<l*
*/ >/6 _ ^
publicinterface UserDAO extends BaseDAO { {id4:^u&;
u)Whr@m
publicList getUserByName(String name)throws 8H`[*|{'
]hV*r@d
HibernateException; &BSn?
:b!s2n!u
publicint getUserCount()throws HibernateException; X"*5+* z]
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publicList getUserByPage(Page page)throws 1k^oS$UT
?Q;=v~-Q
HibernateException; 2st3
x.4m|f0;
} :Llb< MY2
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(**oRwr%
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C/
m(P]k'ZH?
java代码: -D:b*D
1{.9uw"2S
X5w$4Kj&4l
/*Created on 2005-7-15*/ :rP=t ,
package com.adt.dao.impl; asqV~n
9A#i_#[R
import java.util.List; >8[Z.fX
z'7]h TA
import org.flyware.util.page.Page; V28M lP
yIE!j%u
import net.sf.hibernate.HibernateException; z0Z%m@
import net.sf.hibernate.Query; !dT4
5~S5F3
import com.adt.dao.UserDAO; lNv|M)I
s,_m{ to
/** Rk8P
ax/JK
* @author Joa NX&_p!_V
*/ dQG=G%W
public class UserDAOImpl extends BaseDAOHibernateImpl 2 ? 4!K.
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implements UserDAO { J9 I:Q<;
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/* (non-Javadoc) G KeU%x
* @see com.adt.dao.UserDAO#getUserByName 4 H&#q>
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(java.lang.String) og>uj>H&
*/ f,Ghb~y
publicList getUserByName(String name)throws !TcJ)0
&,)&%Sg[
HibernateException { A/?7w
String querySentence = "FROM user in class c4z R*
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+
com.adt.po.User WHERE user.name=:name"; ,tRj4mx
Query query = getSession().createQuery fd9k?,zM
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(querySentence); V G~Vs@c(
query.setParameter("name", name); :MDKC /mC
return query.list(); @KUWxFak
} = WJNWt>
`QY)!$mUIF
/* (non-Javadoc) ;GD]dW#
* @see com.adt.dao.UserDAO#getUserCount() 8JUwf
*/ 4`=mu}Y2
publicint getUserCount()throws HibernateException { |+"(L#wk
int count = 0; t3^&;&[
String querySentence = "SELECT count(*) FROM U`s{Jm
3= ;<$+I6
user in class com.adt.po.User"; R/a*LSe@&
Query query = getSession().createQuery (4-CF3D
CTA3*Gn
(querySentence); cl/_JQ&
count = ((Integer)query.iterate().next hFBe,'3M
]}X
()).intValue(); Vf1^4t
return count; Dum9lj
} k==h|\|
AwF:Iu^3n
/* (non-Javadoc) 8Cv?Z.x5
* @see com.adt.dao.UserDAO#getUserByPage h@wgd~X9
HkVB80hv
(org.flyware.util.page.Page) Jfl!#UAD|n
*/ +qdEq_m
publicList getUserByPage(Page page)throws 3T0"" !Q
j_7mNIr
HibernateException { t.C5+^+%
String querySentence = "FROM user in class <
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z([</D?
com.adt.po.User"; mXs; b
2r^
Query query = getSession().createQuery Mrb)
<QGXy=
(querySentence); 1yY0dOoLG)
query.setFirstResult(page.getBeginIndex()) 3HK\BS
.setMaxResults(page.getEveryPage()); kg\>k2h
return query.list(); |! "eWTJ
} 6D_D' ;o
|
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} IO:G1;[/2L
FML(4BY,
Wh{tZ~c
?|Zx!z ($
X#;bh78&-
至此,一个完整的分页程序完成。前台的只需要调用 Ilm^G}GB
Rbv;?'O$L
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;YL i{
Z;)%%V%o
的综合体,而传入的参数page对象则可以由前台传入,如果用 h2J
x]FJ
eh#(eua0/
webwork,甚至可以直接在配置文件中指定。 vs{s_T7Mz]
R0-j5&^jju
下面给出一个webwork调用示例: lU8Hd|@-
java代码: b5n'=doR/I
lsNd_7k
iO;
7t@]-
/*Created on 2005-6-17*/ ,~W|]/b<q
package com.adt.action.user; FJ?IUy 6
Q#zmf24W
import java.util.List; _v]MsT-q
\xoP)Ub>
import org.apache.commons.logging.Log; 0#^v{DC
import org.apache.commons.logging.LogFactory; <1M-Ro?5k
import org.flyware.util.page.Page; ;t`&n['N>
+^T@sa`[I
import com.adt.bo.Result; |$_sX9\`?|
import com.adt.service.UserService; @U}1EC{A
import com.opensymphony.xwork.Action; H}
g{Cr"Ex
@Do= k
/** ;sFF+^~L
* @author Joa [j'X;tVX{
*/ c~
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publicclass ListUser implementsAction{ $PHvA6D
.#pU=v#/[
privatestaticfinal Log logger = LogFactory.getLog nzeX[*
JqiP>4Uwm^
(ListUser.class); jo@J}`\Zt
jW@Uo=I[
private UserService userService; *-p}z@8
Mf``_=K
private Page page; uu687|Pm
H$4:lH&(
privateList users; h 9W^[6
/&94 eC
/* ,zY$8y]
* (non-Javadoc) 'uEl~> l7
* 2jhxQL
* @see com.opensymphony.xwork.Action#execute() 1|wL\I
*/ $E.I84UfX
publicString execute()throwsException{ N87B8rDl
Result result = userService.listUser(page); ?FcAXA/J{
page = result.getPage(); cExS7~*
users = result.getContent(); *;*r8[U}q
return SUCCESS; rw
#$lP
} J-hbh
&:)Wh[
/** 83q6Sv
* @return Returns the page. ^y%T~dLkp'
*/ V "h
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public Page getPage(){ @;RXLq/8
return page; u.Dz~$T
} CeC6hGR5
~/P[J
/** BThrO d
* @return Returns the users. kZ3ThIk%
*/ ,nm*q#R,0
publicList getUsers(){ [q #\D
return users; C~iL3Cb
} Dm<A
^u8
n6a`;0f[R
/** kW&TJP+5*
* @param page [IhYh<i
* The page to set. Ek]'km!
*/ ?(i{y~
publicvoid setPage(Page page){ *!7O~yQ
this.page = page; d-dEQKI?;
} N<injx
e**qF=HCw
/** [HZv8HU|
* @param users L/G6Fjg^
* The users to set. `+Q%oj#FF
*/ j8lb~0JD
publicvoid setUsers(List users){ 9;-p'C
this.users = users; %8~NqS|=
} a!AA]
SI-Ops~e
/** 'SF<_aS(
* @param userService ^ (zYzd
* The userService to set. W9GVt$T7
*/ %d<"l~<5;
publicvoid setUserService(UserService userService){ 7O-x<P;
this.userService = userService; _zi|
} WEi2=3dV
} SNI)9k(T{
Hja3a{LH
nc|p )
G*P#]eO
^3L0w}#
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, '16b2n+F@#
V[Ui/M!9Z
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 ,1o FPa{?
j+
0I-p
么只需要: 5C5sgR C
java代码: b}TS0+TF
JrRH\+4K
Dwfu.ZJa
<?xml version="1.0"?> j\^CV?}sm'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork a HR"n|7{
y/ef>ZZ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- @QP z#-
M:B=\&.O
1.0.dtd"> 338k?nHxv
U#WF;q0L
<xwork> l)l^[2
_.Uh)-yR
<package name="user" extends="webwork- %aVq+kC h
x-&@wMqkc
interceptors"> |H+UOEiv,p
8NAON5.!
<!-- The default interceptor stack name PBTnIU
CN8Y\<Ar
--> *mvlb
(' &
<default-interceptor-ref H*'IK'O
l?n\i]'
name="myDefaultWebStack"/> JO6)-U$7UG
|imM#wF
<action name="listUser" pJ'"j 6Q
U>}w2bZ*
class="com.adt.action.user.ListUser"> ,M
^<CJ
<param @O^6&\s>
:(*V?WI
name="page.everyPage">10</param> K:#I
<result jkF^-Up.
=R$u[~Xl2X
name="success">/user/user_list.jsp</result> @>Km_Ax
</action> VY=jc~c]v
h^(*Tv-!
</package> CU2*z(]&
_H7x9
y=
</xwork> #( 146
'$]97b7G
>$/>#e~
EDl!w:
l L@XM2"
y(yHt=r
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 HJ[c M6$2
$1L>)S
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。 9w"4K.
1JG'%8}#8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 L2i_X@/
~YWQ2]
e)?
.r9pA;
=|y9UlsD
j[J-f@F \Y
我写的一个用于分页的类,用了泛型了,hoho E,x+JeKV
xHLlMn4M
java代码: r1{@Ucw2
">,|V-H
ag;pN*z
package com.intokr.util; czgO ;3-C
"
9wvPC ^
import java.util.List; yEoF4bt
Ww+IWW@
/** Ad9}9!<
* 用于分页的类<br> x,pjpx
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l'E*=Rn
* %axh`xK#
* @version 0.01 5 ,B_u%bb
* @author cheng V1`o%;j
*/ w(3G&11N?
public class Paginator<E> { K+K#+RBK
privateint count = 0; // 总记录数 (Y? gn)*t
privateint p = 1; // 页编号 j[G
privateint num = 20; // 每页的记录数 $2M$?4S/T
privateList<E> results = null; // 结果 x,@B(9No
GdxnpE
/** g63(E,;;J
* 结果总数 /cQueUME`
*/ vDhh>x(
publicint getCount(){ B:S>wFE(.
return count; i0kak`x0
} }t=!(GOb}
}"P|`"WW
publicvoid setCount(int count){ b)5uf'?-
this.count = count; 1N#|
}ad
}
}Gm>`cw-
S8wLmd>
/** N&+x+;Kx
* 本结果所在的页码,从1开始 $)ijN^hV
* U175{N%3
* @return Returns the pageNo. c&?m>2^6
*/ /}fHt^2H
publicint getP(){ 8hz^%vm
return p; G kl71VX
} %i9E @EV
GxI!{oi2
/** U}e!Wjrc
* if(p<=0) p=1 S.94edQ
* K6/Q}W
* @param p CR`Q#Yi
*/ RYQR(v
publicvoid setP(int p){ t?-n*9,#S
if(p <= 0) 5z8d}
I
p = 1; b"uu
this.p = p; P%:wAYz1^O
} ~"&|W'he[
vkx7paY_
/** JHM9
* 每页记录数量 'qb E=
*/ t~EPn.
publicint getNum(){ ]7F=u!/`<C
return num; Ng2@z<>.
} %Ycy{`
qn<|-hA*
/** R'bTN|Cq
* if(num<1) num=1 +\c5]`
*/ ^T;*M_
publicvoid setNum(int num){ ?FeYN+qR
if(num < 1) G%AbC"
num = 1; \378rQU
this.num = num; 0w\zLU
} %S@ZXf~:
Pg0x/X{t
/** mzaWST]
* 获得总页数 vv3*
j&I
*/ 0d"[l@UU0
publicint getPageNum(){ 7$vYo
_
return(count - 1) / num + 1; a LroD$#
} mPtZO*Fc
EyD=q! ZVZ
/** q77;ZPfs8
* 获得本页的开始编号,为 (p-1)*num+1 jk; clwyz/
*/ Pmr5S4Ka
publicint getStart(){ 6S'yZQ|b
return(p - 1) * num + 1; 8>2.UrC
} j9x<Y]
fcRxp{*zO
/** 'RQ+g}|Ba!
* @return Returns the results. [LjT*bi
*/ L%*!`TN
publicList<E> getResults(){ hYT0l$Ng
return results; W#4 7h7M
} e#L8X
{f
SIF/-{i(X
public void setResults(List<E> results){ [fya)}
this.results = results; @Q
]=\N:
} 7 S#J>*
L3u&/Tn2
public String toString(){ LEbB(x;@
StringBuilder buff = new StringBuilder BOb">6C
JgKO|VO
(); xjuN-
buff.append("{"); ?*G|XnM&
buff.append("count:").append(count); }{K)
4M
buff.append(",p:").append(p); $<dH?%!7
buff.append(",nump:").append(num); 0U(@=7V
buff.append(",results:").append Ga-k
:j9l"5"
(results); <Dl*l{zba
buff.append("}"); VuhGx:Xl
return buff.toString(); *KZYv=s,u
} M)J5;^["
9-VNp;V
} -j#2}[J7
iW]j9} t
v}}F,c(f