Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;Q} H'Wg,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O:3DIT1#>
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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 bZsg7[: C
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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 !u=,b fyH
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分页支持类: fnm:Wa|,%|
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java代码: vs~lyM/
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package com.javaeye.common.util; Co#_Cyxg=9
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import java.util.List; /i)1BaF
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publicclass PaginationSupport { %[C-KQH
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publicfinalstaticint PAGESIZE = 30; _{5t/^w&!
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privateint pageSize = PAGESIZE; h*GU7<F:a
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privateList items; !p~K;p,
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privateint totalCount; E[RLBO[*n
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privateint[] indexes = newint[0]; M :Aik&
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privateint startIndex = 0; d4#Ra%
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public PaginationSupport(List items, int ^BFD -p
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totalCount){ !bi}9w
setPageSize(PAGESIZE); 9k@`{+wmZ
setTotalCount(totalCount); X519}
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setItems(items); Qb;5:U/x
setStartIndex(0); g6. =(je
} \!tS|h
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public PaginationSupport(List items, int 4{r_EV[(
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totalCount, int startIndex){ bu2'JIDR
setPageSize(PAGESIZE); t[ZumQ@HC
setTotalCount(totalCount); !F|iL
setItems(items); k5@_8Rc
setStartIndex(startIndex); dIR6dI
} =abth6#)
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public PaginationSupport(List items, int d^w*!<8
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totalCount, int pageSize, int startIndex){ F& 'HZX
setPageSize(pageSize); Um$a9S8b&
setTotalCount(totalCount); ymsqJ
setItems(items); Mwdw7MZ"S
setStartIndex(startIndex); 69v[*InSd
} ]cv|A^
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publicList getItems(){ ewn/@;E
return items; |UO1v A@
} 2.K"+%
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publicvoid setItems(List items){ \JLiA>@@
this.items = items; JqdNO:8
} n>dM OQb
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publicint getPageSize(){ IrRn@15,
return pageSize; adJoT-8P6
} 2rw<]Ce
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publicvoid setPageSize(int pageSize){ "Jp6EL%
this.pageSize = pageSize; 2Z-BZu K6p
} 3o'SY@'W
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publicint getTotalCount(){ IP1|$b}sq
return totalCount; C3 %, pDh
} \4SFD3$&
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publicvoid setTotalCount(int totalCount){ $Q:5KNF+p
if(totalCount > 0){ 7<=7RPWmD
this.totalCount = totalCount; )W@H
int count = totalCount / o4kNDXP#S
m,u?
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pageSize; >oc7=F<8lS
if(totalCount % pageSize > 0) Lh &L5p7
count++; c3lfmTT6^
indexes = newint[count]; *ihg'
for(int i = 0; i < count; i++){ w?AE8n$8
indexes = pageSize * Oz9k.[j(
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} b>%I=H%g
}else{ ^3`98y.Q
this.totalCount = 0; s8``U~D
} is}Fy>9i
} na
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publicint[] getIndexes(){ utwh"E&W
return indexes; <,0&Ox
} tS2lex%
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publicvoid setIndexes(int[] indexes){ 5b B[o6+
this.indexes = indexes; -o#0Yt}3
} s=huOjKL]
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publicint getStartIndex(){ |y%pP/;&!
return startIndex; 0;TMwE
} a~ REFy
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publicvoid setStartIndex(int startIndex){ cQPH le2
if(totalCount <= 0) N13 <!QQ
this.startIndex = 0; CWkm\=
elseif(startIndex >= totalCount) !wrl.A/P
this.startIndex = indexes Dz)bP{iq"
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[indexes.length - 1]; A|>a
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elseif(startIndex < 0) wCvD4C.WH
this.startIndex = 0; t9pPG {1
else{ nbpN+a%
this.startIndex = indexes 7<.f&1MgI
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[startIndex / pageSize]; '~ ]b;nA
} ij hMJ?3
} {/7'uD\
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publicint getNextIndex(){ !s)2H/KM 8
int nextIndex = getStartIndex() + $]81 s`
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pageSize; NHc+QMbou(
if(nextIndex >= totalCount) 6-X7C9`C
return getStartIndex(); N&>D/Z;"
else QW2% Gv:
return nextIndex; \iVYhl
} 1<R
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publicint getPreviousIndex(){ &2\.6rb.
int previousIndex = getStartIndex() - y6jTT%
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pageSize; M(3E
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if(previousIndex < 0) 6
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return0; % 9WWBxS
else *`jEg=)
return previousIndex; ZRxB" a'
} i&LbSxUh9
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} mU&J,C
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抽象业务类 jY?%LY@5I
java代码: *smo{!0Gg
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/** :!A@B.E
* Created on 2005-7-12 z(%Zji@!N
*/ W4YC5ZH{l
package com.javaeye.common.business; krl yEAK=
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import java.io.Serializable; /cjf 1Dc
import java.util.List; H+0 *
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import org.hibernate.Criteria; a,tP.Xsl
import org.hibernate.HibernateException; j/Kw-h ,5"
import org.hibernate.Session; Kc{wv/6}T
import org.hibernate.criterion.DetachedCriteria; T@S+5(
import org.hibernate.criterion.Projections; ]jYl:41yI
import dvj`%?=
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org.springframework.orm.hibernate3.HibernateCallback; r-V./M@L
import l;;:3:
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org.springframework.orm.hibernate3.support.HibernateDaoS eeX)JC0A
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upport; {"y6l
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import com.javaeye.common.util.PaginationSupport; @)0gXg
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public abstract class AbstractManager extends DuFlN1Z
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HibernateDaoSupport { O,;SA
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privateboolean cacheQueries = false; G
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privateString queryCacheRegion; /;>EyWW
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publicvoid setCacheQueries(boolean #QB`'2)vw
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cacheQueries){ P"#^i<ut@T
this.cacheQueries = cacheQueries; Av[jFk
} $OO[C={v[
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publicvoid setQueryCacheRegion(String *!Dzst-J3
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queryCacheRegion){ 0Nfj}sXCWE
this.queryCacheRegion = %|I|Mc
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queryCacheRegion; 4>W`XH
} L9.#/%I\
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publicvoid save(finalObject entity){ e'`oisJU?q
getHibernateTemplate().save(entity); N4:'X6u;
} QJ/SP
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publicvoid persist(finalObject entity){ o6r4tpiR5
getHibernateTemplate().save(entity); uu:)jx i
} Dn[1BWM/7
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publicvoid update(finalObject entity){ JjmL6(*ui
getHibernateTemplate().update(entity); ymzm x$o=
} S;NXOsSu
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publicvoid delete(finalObject entity){ zxh"@j$?
getHibernateTemplate().delete(entity); =
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} gr;M
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publicObject load(finalClass entity, q2Kn3{
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finalSerializable id){ |h7v}Y
return getHibernateTemplate().load H07j&
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(entity, id); 5c"kLq6r
} E;qwoTmul
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publicObject get(finalClass entity, X=3@M_Jzo
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finalSerializable id){ |(%H O@i
return getHibernateTemplate().get vf2K2\fn
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(entity, id); /K^cU;E,
} (Y>MsqwWfC
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publicList findAll(finalClass entity){ (yP55PC
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return getHibernateTemplate().find("from
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" + entity.getName()); xeI{i{8
} "YL-!P
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publicList findByNamedQuery(finalString '!R,)5l0h
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namedQuery){ _#C}hwOR>X
return getHibernateTemplate Xo`1#6xsE
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().findByNamedQuery(namedQuery); v\ Ljm,+
} |=LkV"_v
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publicList findByNamedQuery(finalString query, >-P0wowL
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finalObject parameter){ 'T[zh#v>S
return getHibernateTemplate kgz{m;R
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().findByNamedQuery(query, parameter); Q$1K{14I
} Nd!VR+IZ
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publicList findByNamedQuery(finalString query, F:S,{&jB
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finalObject[] parameters){ ~-5@- V
return getHibernateTemplate D,\=zX;
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().findByNamedQuery(query, parameters); $]kg_l)
} 3J
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publicList find(finalString query){ bSf(DSqx
return getHibernateTemplate().find Zjg\jo
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(query); ?Z>.G{Wm@
} "!tw
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publicList find(finalString query, finalObject A+I&.\QAR
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parameter){ N;'HR)
return getHibernateTemplate().find s.` d<(X?
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(query, parameter); G%!\ p:w
} vo(NB
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public PaginationSupport findPageByCriteria L\NZDkd
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(final DetachedCriteria detachedCriteria){ 7E`(8i
return findPageByCriteria hFMst%:y$
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); AwUc{h l<
} \oX8/-0 f
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public PaginationSupport findPageByCriteria PuCDsojclh
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(final DetachedCriteria detachedCriteria, finalint o^Yspp
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startIndex){ hF"g91P
return findPageByCriteria QO{=Wi-
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(detachedCriteria, PaginationSupport.PAGESIZE, eJw="
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startIndex); (YHvGGr
} bz0P49%
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public PaginationSupport findPageByCriteria P4j 8`}&/
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(final DetachedCriteria detachedCriteria, finalint xwnoZ&h
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pageSize, vo
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finalint startIndex){ t-i6 FS-
return(PaginationSupport) ]<T8ZA_Y;
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getHibernateTemplate().execute(new HibernateCallback(){ ;{f?? G
publicObject doInHibernate ZuvPDW%
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(Session session)throws HibernateException { Hpi%9SAM
Criteria criteria = `n`"g<K)Q
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detachedCriteria.getExecutableCriteria(session); 7TkxvSL X
int totalCount = vM7v f6
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((Integer) criteria.setProjection(Projections.rowCount {Mr~%y4
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()).uniqueResult()).intValue(); i9eyrl+!
criteria.setProjection s
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(null); s!ZW'`4!z
List items = z8/xGQn
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criteria.setFirstResult(startIndex).setMaxResults +K%pxuVh
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(pageSize).list(); pEVgJ/>
PaginationSupport ps = D!}K)T1~R
/.)[9bQ<
new PaginationSupport(items, totalCount, pageSize, -~\.n
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startIndex); 5m^Hi}S_
return ps; a-5HIY5
} "f|(@a
}, true); >u5g?yzw
} 58&{5YpS
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public List findAllByCriteria(final ?#m<\]S<
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DetachedCriteria detachedCriteria){ *el(+ib%
return(List) getHibernateTemplate yYToiW *
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().execute(new HibernateCallback(){ nFe` <Al$N
publicObject doInHibernate m0j|58~
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(Session session)throws HibernateException { W&e'3gk _
Criteria criteria = cRh\USS
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detachedCriteria.getExecutableCriteria(session); H5Ux.]y
return criteria.list(); .vN%UNu
} .6#cDrK
}, true); /z1p/RiX
} VJN/#
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public int getCountByCriteria(final >X[|c"l.
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DetachedCriteria detachedCriteria){ X_u@D;$
Integer count = (Integer) ;h9-}F
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getHibernateTemplate().execute(new HibernateCallback(){ %9T~8L
@.
publicObject doInHibernate ]bTzbu@
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(Session session)throws HibernateException { m']9Q3-
Criteria criteria = EWb(uWC8h
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detachedCriteria.getExecutableCriteria(session); LBmM{Gu
return cX%:
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criteria.setProjection(Projections.rowCount %1\v7Xw{9
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()).uniqueResult(); q Vm"f,ruo
} 4D^ M<Xn
}, true); W?qpnPW
return count.intValue(); 7~wFU*P1
} 5zNSEI"PY
} }+Rgx@XZ\
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用户在web层构造查询条件detachedCriteria,和可选的 tYs8)\{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t_jyyHxoZ:
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PaginationSupport的实例ps。 vG ]GQ#
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ps.getItems()得到已分页好的结果集 _urG_~q
ps.getIndexes()得到分页索引的数组 c ]>DI&$;J
ps.getTotalCount()得到总结果数 6OL41g'
ps.getStartIndex()当前分页索引 lSH ZV
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ps.getNextIndex()下一页索引 XkPv*%Er8
ps.getPreviousIndex()上一页索引 XC|*A$x,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 fL!V$]HNt
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 T/[f5?p
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一下代码重构了。 j~Q}F |i8
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我把原本我的做法也提供出来供大家讨论吧: DH5bpg&T
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首先,为了实现分页查询,我封装了一个Page类: m6b$Xyq[
java代码: gUl1CH&
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/*Created on 2005-4-14*/ i<%m Iq1L
package org.flyware.util.page; A -Mj|V
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/** r"R(}`<,
* @author Joa N99[.mErU
* ^_@r.y]
*/ :<L5sp
publicclass Page { /@VsqD
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/** imply if the page has previous page */ -*?p F_*w
privateboolean hasPrePage; R"@7m!IA
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/** imply if the page has next page */ E W`W~h[
privateboolean hasNextPage; jDR')ascn
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/** the number of every page */
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privateint everyPage; <mL%P`Jj
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/** the total page number */ 5J
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privateint totalPage; Ua %UbAt
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/** the number of current page */
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privateint currentPage; ;_}~%-_
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/** the begin index of the records by the current gNqAj# m
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query */ u t$c)_
privateint beginIndex; j !`B'{cH
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/** The default constructor */ x|8^i6xB
public Page(){ .46#`4av
/hL\,x2
} g0PT8]8
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/** construct the page by everyPage A_Rrcsl4
* @param everyPage >z(wf>2J
* */ 'r\ 4}Ik
public Page(int everyPage){ %,0%NjK
this.everyPage = everyPage; OVZP x%a
} 9UV9h_.x
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/** The whole constructor */ !}_b|
public Page(boolean hasPrePage, boolean hasNextPage, EkjgNEXq
uAUp5XP|Z
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int everyPage, int totalPage, 28a$NP\KW
int currentPage, int beginIndex){ >p0KFU
this.hasPrePage = hasPrePage; t8P PE
this.hasNextPage = hasNextPage; _g~2R#2Q
this.everyPage = everyPage; kO1}?dWpa
this.totalPage = totalPage; nq1
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this.currentPage = currentPage; 7tRi"\[5
this.beginIndex = beginIndex; <YH=3[
} HJIC<U
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/** 6kN:*
* @return 0Qnd6mb
* Returns the beginIndex. \9`#]#1bx5
*/ -U>y
publicint getBeginIndex(){ `PgdJrE
return beginIndex; k[%aCGo
} lNz]HiD
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/** x:fW~!Xc6
* @param beginIndex 3#c3IZ-;
* The beginIndex to set. YHB9mZi
*/ 1'JD =
publicvoid setBeginIndex(int beginIndex){ 0OnV0SIL
this.beginIndex = beginIndex; vQ1 v#Z
} QTH7grB2v
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/** 2z\e\I
* @return MG{l~|\x)
* Returns the currentPage. I-DXb
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*/ 8PBvV[
publicint getCurrentPage(){ _[t8rl
return currentPage; ?T!)X)A#
} yz8jU*H
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/** Z.1>
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* @param currentPage 6@V~0DG
* The currentPage to set. v7,$7@$:\
*/ 6~xBi(m`
publicvoid setCurrentPage(int currentPage){ MjD75hIZ
this.currentPage = currentPage; l$XPIC~H
} Rko M~`CT
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/** i{Ds&{
* @return UE.4qY_7
* Returns the everyPage. , jU5|2
*/ $!B}$I;cd
publicint getEveryPage(){ ;j9\b9m
return everyPage; w!&~??&=}
} QI_4*
) #+^
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/** l63hLz
* @param everyPage vUesV%9hq
* The everyPage to set. _las;S'oa
*/ H43MoC
publicvoid setEveryPage(int everyPage){ }Wh6zT)
this.everyPage = everyPage; S6g<M5^R
} LT VF8-v
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/** t e,[f
* @return Y`BRh9Sa
* Returns the hasNextPage. (V?: ]
*/ z~{&}Em ~
publicboolean getHasNextPage(){ ypdT&5Mqb!
return hasNextPage; m@Rtlb
} Ba'LRz
CU)|-*uiK
/** -7{$Vj
* @param hasNextPage ])}]/Qw
* The hasNextPage to set. Ig6T g ?
*/ :j^FJ@2_
publicvoid setHasNextPage(boolean hasNextPage){ x@KZ]
this.hasNextPage = hasNextPage; S DLvi!y
} B9,^mE#
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/** E3aDDFDH
* @return XYrJ/!*.
* Returns the hasPrePage. )"+2Z^1-
*/ $?P22"/p
publicboolean getHasPrePage(){ jE\Sm2G9
return hasPrePage; om h{0jA0
} `bjizS'^
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/** ,yd= e}lQx
* @param hasPrePage _zWfI.o
* The hasPrePage to set. T0z n,ej
*/ \S~Vx!9w
publicvoid setHasPrePage(boolean hasPrePage){ XB59Vm0E=
this.hasPrePage = hasPrePage; !\Xm!I8
} T r0B[QF
2L?!tBw?1
/** $~;D9
* @return Returns the totalPage. Bi,;lR5
* GH1"xR4!
*/ [`RX*OH2
publicint getTotalPage(){ \QE)m<GUe
return totalPage; ^=
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} ]X Z-o>+,
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/** !> }.~[M
* @param totalPage ,#?uJTLH
* The totalPage to set. <FI-zca
*/ ma'FRt
publicvoid setTotalPage(int totalPage){ !V2/A1?
this.totalPage = totalPage; G uQ=gN
} UFAL1c<V
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} >K9#3
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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 y\dEk:\)
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个PageUtil,负责对Page对象进行构造: o6
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java代码: R218(8S
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/*Created on 2005-4-14*/ \.YS%"Vz
package org.flyware.util.page; 4lhw3,5
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import org.apache.commons.logging.Log; '52~$z#m
import org.apache.commons.logging.LogFactory; w}Uhd,
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/** !l]dR@e
* @author Joa Wjhvxk
* &nBa=Enf
*/ J]f3CU,<N
publicclass PageUtil { e@:sR
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privatestaticfinal Log logger = LogFactory.getLog AKMm&(fh%
^P151*=D
(PageUtil.class); nWQ;9_qBB
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/** `;%]'F0`
* Use the origin page to create a new page #Zrlp.M4
* @param page =] *.ZH#h
* @param totalRecords mU}F!J#6
* @return 4jD2FFG-
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*/ {43>m)8+
publicstatic Page createPage(Page page, int Y%`xDI
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totalRecords){ C4TE-OM8
return createPage(page.getEveryPage(), s(X;Eha
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page.getCurrentPage(), totalRecords); |$5[(6T|
} #9K-7je;j
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/** 3Zi@A4Wu
* the basic page utils not including exception k'0Pi6
6 G=j6gK%P
handler ^%O]P`$
* @param everyPage xhcK~5C
* @param currentPage ZXm/A0)S
* @param totalRecords 4:g R r
* @return page }.s~T#v
*/ |4'Y/re
publicstatic Page createPage(int everyPage, int y+7w,m2
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currentPage, int totalRecords){ \7CGUB>L
everyPage = getEveryPage(everyPage); ai0XL}!+
currentPage = getCurrentPage(currentPage); M)SEn/T-
int beginIndex = getBeginIndex(everyPage, 8#vc(04(
/ X1 x
currentPage); LD!Q8"
int totalPage = getTotalPage(everyPage, GvBHd%Ot
6?w0
totalRecords); +SwR+H)?
boolean hasNextPage = hasNextPage(currentPage, JQ"U4GVp
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totalPage); JH7<
boolean hasPrePage = hasPrePage(currentPage); &RfC"lc
ocs+d\
returnnew Page(hasPrePage, hasNextPage, 1dK*y'rx
everyPage, totalPage, -Z's@'*
currentPage,
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beginIndex); K5lmVF\$P
} jYKor7KTqT
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privatestaticint getEveryPage(int everyPage){ X7rMeu
return everyPage == 0 ? 10 : everyPage; uCcYPvm
} U*)8G
-,U3fts
privatestaticint getCurrentPage(int currentPage){ aTt12Sc
return currentPage == 0 ? 1 : currentPage; '*3h!lW1.
} kBffF@{
?nL.w
privatestaticint getBeginIndex(int everyPage, int d@qsdYu-*
*6VF
$/rP
currentPage){ fZoHf\B]{
return(currentPage - 1) * everyPage; jbAx;Xt'=M
} `^)jLuyu
'ET~
privatestaticint getTotalPage(int everyPage, int : 2EDjW
4M2j!Sw
totalRecords){ *6>.!&
int totalPage = 0; >G%o,9i
dUhY\v oQ
if(totalRecords % everyPage == 0) ajEjZ6
totalPage = totalRecords / everyPage; @<elq'2
else Fx2bwut.K
totalPage = totalRecords / everyPage + 1 ; ?U2<
9?SZNL['V
return totalPage; U[ 0=L`0e
} va0{>Dc+
~Yy>zUH^X
privatestaticboolean hasPrePage(int currentPage){ X"fb; sGT
return currentPage == 1 ? false : true; 5;YMqUkw
} Ck)*&
s6@DGSJ
privatestaticboolean hasNextPage(int currentPage, ATK_DEAu
C)`Fv=]R
int totalPage){ 85LAYaw
return currentPage == totalPage || totalPage == z62;cv
j3{D^|0bP
0 ? false : true; yjF1}SQ
} 7Mg=b%IYs
ci?qT,&
0|{u{w@!`
}
@fl-3q
lIW
}EM
bAx-"Lu
SMpH._VFeE
zo4qG+>o
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Y!nJg1
3`t%g[D1
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 PoxK{Y
^rifRY-,yO
做法如下: xe^Gs]fm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 e4 >_v('
*GL/aEI<$
的信息,和一个结果集List: ~T1XLu
java代码: M`,)w i
OCBgR4I
JzQ )jdvp
/*Created on 2005-6-13*/ hhCrUn"
package com.adt.bo;
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Bu#VMkchJ
import java.util.List; 6\g cFfo
YQj 2
import org.flyware.util.page.Page; @$[?z9ck"
PoG-Rqe
/** b4[bL2J$h1
* @author Joa /`wvxKX
*/ PHZ0P7
publicclass Result { @~^5l
J IUx
private Page page; pKpUXfQu
X-K=!pET
private List content; {zQ8)$CQ
ChGYTn`X
/** fF7bBE)L/|
* The default constructor `d5%.N
*/ 1Q<^8N)pf
public Result(){ )u[emv$
super(); A kC1z73<
} %A1o.{H
TO]@
Zu1
/** ~*z% e*EL
* The constructor using fields gOSJM1Mr3
* ME46V6[LX]
* @param page =P't(<
* @param content zv0l,-o
*/ Yc_8r+;(
public Result(Page page, List content){ TaKLzd2
this.page = page; PgtJ3oq[}
this.content = content; 6dabU*
} J8uLJ
v+46QK|I&
/** /:~\5}tW
* @return Returns the content. 6e9,PS
*/ o<BOYrS
publicList getContent(){ ?!A7rb/tj
return content; YIoQL}pX
} GpY"fc%
e7Xeo +/
/** 6#7Lm) g8
* @return Returns the page. m$}R%
*/ KL1/^1
public Page getPage(){ \^L`7cBL
return page; 8 OY 3A
} EofymAi%
>,gg5<F-E
/** x@P y>f2
* @param content $PTP/^
* The content to set. m0ER@BXRn
*/ {o_X`rgrL
public void setContent(List content){ _=_Px@<Q
this.content = content; ,k )w6)
} 1+szG1U=
=RA /
/** b6nsg|
* @param page }()5"QB
* The page to set. y"bByd|6
*/ 0m%|U'm|j
publicvoid setPage(Page page){ gd%NkxmW
this.page = page; q)X$^oE!6
} OK[T3/v,
} ^t` k0<
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-(
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1f
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2. 编写业务逻辑接口,并实现它(UserManager, 27
]':A4_
TSTl+W
UserManagerImpl) ]zj9A]i:a
java代码: R "n5
^U
`[(kz=
[~-9i&Z
/*Created on 2005-7-15*/ q)LMm7
package com.adt.service; :o0JY= 5
;&<{ey
import net.sf.hibernate.HibernateException; "?]{%-u
LJd5;so-
import org.flyware.util.page.Page; diJLZikk
c`J.Tm[_u
import com.adt.bo.Result; <sWprR
h1B? 8pD
/** .`HYA*8_
* @author Joa E27vR 7
*/ |L%Z,:yO
publicinterface UserManager { aoMqSwF=
/Y9>8XSc
public Result listUser(Page page)throws *7CV^mDm
:[wsKFaV+
HibernateException; Lm*e5JnV
F"&~*m^+
} [B+yyBtx
JlH&??
.>=(' -
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<'qeXgi
java代码: !nqUBa
>p)MawT]
l1T m`7}
/*Created on 2005-7-15*/ g[1gF&
package com.adt.service.impl; F~T]u2qt
}Mst jm
import java.util.List; }#L^! \V}
SX<` {x&L
import net.sf.hibernate.HibernateException; iP
=V8g?L
d74d/l1*{
import org.flyware.util.page.Page; 2)G
%)'
import org.flyware.util.page.PageUtil; -e_hrCW&9
3kw,(-'1
import com.adt.bo.Result; Ja,wfRq
import com.adt.dao.UserDAO; s3~lT.
import com.adt.exception.ObjectNotFoundException; &M46&^Jho
import com.adt.service.UserManager; kStnb?nk
v=0(~<7B
/** GR&z,
* @author Joa .:@Ykdm4I
*/ fKeT,U`W
publicclass UserManagerImpl implements UserManager { 'C`U"I
Bzkoo J
private UserDAO userDAO;
3L<wQ(
7op`s5i
/** &+cEV6vb+
* @param userDAO The userDAO to set. >pU$wq|i
*/ lpQSup
publicvoid setUserDAO(UserDAO userDAO){ =y
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this.userDAO = userDAO; .n#@$
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} Mmxlp.l
5]NqRI^0
/* (non-Javadoc) Kf>A\l^X7
* @see com.adt.service.UserManager#listUser C>-aIz!y
O[I\A[*
(org.flyware.util.page.Page) BcL{se9<
*/ ~<O7$~
public Result listUser(Page page)throws :yRo3c
D ~stM
HibernateException, ObjectNotFoundException { `7[EKOJ3g
int totalRecords = userDAO.getUserCount(); 5"CZh.J
if(totalRecords == 0) igIRSN}h
throw new ObjectNotFoundException 3N dq>
D>HOn^
("userNotExist"); y+X2Pl
page = PageUtil.createPage(page, totalRecords); M.x=<:upp
List users = userDAO.getUserByPage(page); [0(B>a3J
returnnew Result(page, users); N/Z2hn/m
} YUx.BZf7
419x+3>}
} Xnz3p"
6hlc1?
oI=fx Sjd
"Om=N@?
q@Zn|NR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 9f2UgNqe9
G~Hzec{#tg
询,接下来编写UserDAO的代码: eFaO7mz5V%
3. UserDAO 和 UserDAOImpl: SO IHePmwK
java代码: 1M}5>V{
/.3}aj;6
Gf,`
/*Created on 2005-7-15*/ IEXt:
package com.adt.dao; '9S8}q
!
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import java.util.List; 'JCZ]pZ
>64P6P;S
import org.flyware.util.page.Page; uEktQ_u[
+@94;me
import net.sf.hibernate.HibernateException; 8"U. Hnu
G`n_YH084
/** <L"GqNuRQ
* @author Joa v{(^1cX
*/ 7uKNd
*%
publicinterface UserDAO extends BaseDAO { { &"CH]r
spdvZU=}
publicList getUserByName(String name)throws U>cV|
\!k1a^ZP
HibernateException; d/ARm-D
eZSNNgD<:
publicint getUserCount()throws HibernateException; &X|#R1\
e7m*rh%5>
publicList getUserByPage(Page page)throws JTr vnA
SSPHhAeH8
HibernateException; A Y*e@nk\
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} XiL~TCkx4
$"FQj4%d
jBgP$g
O_ChxX0KP
QWD'!)Zb
java代码: xD5:RE~g
j/fzzI0@
f|B=_p80
/*Created on 2005-7-15*/ JBXrFC;
package com.adt.dao.impl; v3aYc:C
}q $5ig
import java.util.List; eO?p*"p" F
N>XS=2tzN
import org.flyware.util.page.Page; $})g?Q
r[BVvX/,F
import net.sf.hibernate.HibernateException; l8I /0`_
import net.sf.hibernate.Query; q=%RDG+
9;r)#3Q[^
import com.adt.dao.UserDAO; hEBY8=gK
]^lw*724'>
/** }% `.h"
* @author Joa A/u)# ^\
*/ zG ^$"f2
public class UserDAOImpl extends BaseDAOHibernateImpl P(H8[ ,
7*
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implements UserDAO { *~t6(v?
v.pBX<
/* (non-Javadoc) tnPv70m
* @see com.adt.dao.UserDAO#getUserByName X$ s:>[H
t=Xv;=daB
(java.lang.String) SZ,YS
4M
*/ |y0(Q V
publicList getUserByName(String name)throws CDP
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d8[J@M53|T
HibernateException { L1cI`9
String querySentence = "FROM user in class ZUoxMm
X~lVVBO
com.adt.po.User WHERE user.name=:name"; :-/M?,Q"
Query query = getSession().createQuery t.7?
\/: {)T~
(querySentence); k< y>)
query.setParameter("name", name); \.-}adKg
return query.list(); Nv(9N-9r
} a0D%k: k5
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uX7b
/* (non-Javadoc) k@/sn(x
* @see com.adt.dao.UserDAO#getUserCount() fh](K'P#^
*/ -Z 4e.ay5
publicint getUserCount()throws HibernateException { +y&Tf#.V/A
int count = 0; y%%}k
String querySentence = "SELECT count(*) FROM bgK'{_o-
7R6ry(6N
user in class com.adt.po.User"; l)Crc-:}4j
Query query = getSession().createQuery ^; )8VP6
mj9 <%P
(querySentence); +VO-oFE |
count = ((Integer)query.iterate().next L&u$t}~)
@cFJeOC|
()).intValue(); czS+<
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return count; S7/eS)SQR
} uTKD 4yig
5@+,Xh,H|t
/* (non-Javadoc) ,N!o
* @see com.adt.dao.UserDAO#getUserByPage 2E}*v5b,
P_*" dza
(org.flyware.util.page.Page) <Bw^!.jAF
*/ X!9 B2w
publicList getUserByPage(Page page)throws #,":vr
j$?{\iXZ
HibernateException { C-\S/yd
String querySentence = "FROM user in class ;<j0f~G`
9}PhN<Gd
com.adt.po.User"; i*/Yz*<
Query query = getSession().createQuery D/vOs[X
o,
NT e5
(querySentence); 5N/%v&1
query.setFirstResult(page.getBeginIndex()) D ,o}el
.setMaxResults(page.getEveryPage()); ^/\Of{OZ-
return query.list(); PH+S};Uxv
} B{'( L|
g^}8:,F_
} u>kN1k Q8
8,?h~prc
{q`jDDM
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`>
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至此,一个完整的分页程序完成。前台的只需要调用 6L"%e!be6
Z0Vl+
userManager.listUser(page)即可得到一个Page对象和结果集对象 |mGFts}0o'
O(D~_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 CG Y]r.O*
7"20hAd
webwork,甚至可以直接在配置文件中指定。 P<X\%_Iat
n1ly
y0%u
下面给出一个webwork调用示例: G9xmmc
java代码: :6vm+5!
4^WpS/#4
YjxF}VI~<
/*Created on 2005-6-17*/ 3%E }JU?MM
package com.adt.action.user; cx&>#8s&
}o(zj=7
import java.util.List; MvK !u
_AAaC_q
import org.apache.commons.logging.Log; !g5xq
import org.apache.commons.logging.LogFactory; bpH^:fyLU`
import org.flyware.util.page.Page; 62k^KO6Y
a
yCY~=i
import com.adt.bo.Result; ?[g=F <r
import com.adt.service.UserService; "Zl5<
import com.opensymphony.xwork.Action; fI{&#~f4C
[5G6VNh=
/** 6p?,(
* @author Joa . 1KhBgy^K
*/ d1AioQ9
publicclass ListUser implementsAction{ iOU6V
mz,
privatestaticfinal Log logger = LogFactory.getLog lQ" p !
gkES5Q
(ListUser.class); ="Ho%*@6
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private UserService userService; gy#/D& N[
3RYpJAH
private Page page; u%}nw :>
p"n$!ilbm
privateList users; fGUE<l
>O*IQ[r-
/* CE#gfP
* (non-Javadoc) 8u6:=fxb
* VH9dleZ
* @see com.opensymphony.xwork.Action#execute() /{+y2.{j
*/ mRL"nC
publicString execute()throwsException{ 95 ;x=ju
Result result = userService.listUser(page); B@&4i?yJ
page = result.getPage(); CG0
M
users = result.getContent(); !W5 (
return SUCCESS; qU%/W|LY
} r^FhTzA=1
=Xi07_8Ic<
/** 3Dng1}
* @return Returns the page. :~2vJzp@?
*/ 2% L LSa
public Page getPage(){ "P7nNa
return page; ;<&*rnH
} ar__ Pf6r
Jm xH"7hTE
/** &,zq%;-f
* @return Returns the users. llcb~
*/ ?[@J8
publicList getUsers(){ f .Q\Z'S^
return users; AL9chYP}/
} n^Hm;BiE#
NQBpX
/** s}w{:Hk,x8
* @param page hs^zTZ_
* The page to set. tSr8 zAV
*/ oI
}VV6vO
publicvoid setPage(Page page){ ?}wk.gt>
this.page = page; #M9~L[nFS
} G<}()+L
?zh9d%R
/** A\4D79>x
* @param users -ws? "_w
* The users to set. \k .{-nh
*/ b*a#<K$T_
publicvoid setUsers(List users){ 7m4aoK
this.users = users; ^q{9
} cpL7!>^=
'@o;-'b
/** ]<ldWL
* @param userService }AB,8n`
* The userService to set. ~IYUuWF(
*/ tr<Nm6!
publicvoid setUserService(UserService userService){ s'!Cp=xQF"
this.userService = userService; J\+0[~~
} B^4&-z2|
} u(@$a4z
HVi'eNgo
I(i}c~R
~ksi</s
KaPAa:Q
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, :flx6,7D
@i2E\}
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 8<X#f
!
B,?T%
么只需要: %KsEB*'"
java代码: mk;&yh
94h]~GqNi
&v56#lG
<?xml version="1.0"?> [4YTDEv%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >"^ O"E
Nv#t:J9f
1.0//EN" "http://www.opensymphony.com/xwork/xwork- J?V? R
`` ,fodA8
1.0.dtd"> h
k]
N6+@
6.sx?Y YM
<xwork> CSJdvxb
{#ZlM
<package name="user" extends="webwork- *:Y%HAy*
RSfQNc9Z
interceptors"> 2GP=&K/A
PC~Y8,A|.t
<!-- The default interceptor stack name I3aNFa}
6/5YjO|a
--> F0GxH?
<default-interceptor-ref (l\1n;s*B
!\-{D$E?H
name="myDefaultWebStack"/> +9M^7/}H
:0Bq^G"ge
<action name="listUser" C6VLy x
6c}h(TkB
class="com.adt.action.user.ListUser"> "H7dft/
<param Pr3qo4t.L
G? ])o5
name="page.everyPage">10</param> t>L;kRujVJ
<result FtpK)9/4
I4'5P}1yp
name="success">/user/user_list.jsp</result> )F}F_Y
</action> N:S/SZI
|z9*GY6RU
</package> ZGBd%RWjG_
/ kE6@
</xwork> %aHB"vi6
2y//'3[
SON-Z"v
+NeOSQSj
(uXL^oja
vq0Vq(V=
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 tRs [ YK
p)jk>j B
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。 rV2WnAb[H&
-z-C*%~
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 *F+KqZ.2
g,Lq)'N;O
P2NQHX
^|/TC!v]M
]3x?
我写的一个用于分页的类,用了泛型了,hoho \9cbI3rGz
HguT"%iv
java代码: _>5(iDW0
Vp#JS3Y
E-4b[xNj*+
package com.intokr.util; 6hw=
|ax3sAg
import java.util.List; sGi"rg#
S
^"y4-2
/** )SaGH3~*C
* 用于分页的类<br> ?ME6+Z\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> [glLre^
* 9%k2'iV7
* @version 0.01 ?8I?'\F;
* @author cheng
zkt+7,vI
*/ zvvhFN2s
public class Paginator<E> { $ZUdT
privateint count = 0; // 总记录数 18|m)(W
privateint p = 1; // 页编号 '<jyw
privateint num = 20; // 每页的记录数 u#Pa7_zBj]
privateList<E> results = null; // 结果 srr
:!5
|v`AA?@{8
/** \MsTB|Z
* 结果总数 Umz KY
*/ yg`j-9[8
publicint getCount(){ {}>0e:51
return count; %oF}HF.
} $I!XSz"/e
_ q(ko/T
publicvoid setCount(int count){ j:^#rFD4?
this.count = count; }d[ kxo
} !Xh=k36
g$":D
/** #9B)Xx!g
* 本结果所在的页码,从1开始 &Q%zl9g(g
* qt"G[9;
* @return Returns the pageNo. k|v3.< -
*/ j?A/#
publicint getP(){ &D>G8
return p; Nu0C;B66
} |Z|-q"Rf
|+"<wEKI
/** niiA7Ux
* if(p<=0) p=1 ySk R>y
* -0d0t!
* @param p QMA%$
*/ % "kPvI3Y
publicvoid setP(int p){ bH-ub2@qO
if(p <= 0) P#E &|n7DT
p = 1; Yab%/z2:
this.p = p; _A M*@|p,
} {i1|R"ta
!xz eM VI
/** O6Vtu Ws%
* 每页记录数量 $CxKuB(
*/ Yw22z #K
publicint getNum(){ Kh"?%ZIa
return num; N@;?CKU
} -<c=US
jTf@l?|
/** CHdX;'`*
* if(num<1) num=1 aC^\(wp[
*/ K#l:wH_
publicvoid setNum(int num){ _ ?TN;
if(num < 1) gMv.V{vD
num = 1; )}''L{k-
this.num = num; ?RX3MUN
} kJWn<5%ayg
K}2Erm%A@y
/** (ScxLf=]
* 获得总页数 #&cI3i
*/ +y,T4^{
publicint getPageNum(){ OGBHos
return(count - 1) / num + 1; "HX<,l8f%
} Qf58ig-vCY
];} Wfl
/** Q;MT"=RW
* 获得本页的开始编号,为 (p-1)*num+1 t$+?6E
*/ @M<|:Z %.@
publicint getStart(){ 7@C<oy_bb
return(p - 1) * num + 1; x9NEFtqjm
} ".f ;+wH
xpNH?#&
/** u=Fv2
* @return Returns the results. :f Kl]XO
*/ ylUb9KusOx
publicList<E> getResults(){ d]`CxI]
return results; \/E>4)MD y
} B*qi_{Gp
Pih tf4i
public void setResults(List<E> results){ lNNv|YiL
this.results = results; sD<a+Lw}x
} ZjT,pOSyb
[]x#iOnC&
public String toString(){ oYHj~t
StringBuilder buff = new StringBuilder l_3`G-`2
,t}vz 7
(); -_ I_W&
buff.append("{"); -)s qc
P
buff.append("count:").append(count); KTK <gV9:
buff.append(",p:").append(p); (w&F/ynO:
buff.append(",nump:").append(num); %/EVUN9=
buff.append(",results:").append /TE_W@?^
UT>s5C
(results); M\C"5%2Mu
buff.append("}"); +_s #2
return buff.toString(); .R`5Qds*l
} )js)2L~
2`.cK 3
} hS_6
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