Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !Q=H)\3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5
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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 h\afO
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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 ]cLO-A
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分页支持类: ,
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java代码: E\&~S+:Xp
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package com.javaeye.common.util; ~itrM3^"w
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import java.util.List; 3G|n`dj
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publicclass PaginationSupport { pme5frM|
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publicfinalstaticint PAGESIZE = 30; H'Q4IRT
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privateint pageSize = PAGESIZE; #x!h
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privateList items; 7<['4*u
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privateint totalCount; aaW(S K
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privateint[] indexes = newint[0]; V(n7hpS
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privateint startIndex = 0; hOjy$Z
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public PaginationSupport(List items, int 6jT+kq)
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totalCount){
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setPageSize(PAGESIZE); K9h{sC
setTotalCount(totalCount); ~Qjf-|
setItems(items); Kt5;GUV
setStartIndex(0); ^F/gJ3_;
} [;yEG$)K
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public PaginationSupport(List items, int *CG-F=
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totalCount, int startIndex){ w4w[qxV>
setPageSize(PAGESIZE); MBZ/Pzl~
setTotalCount(totalCount); 5lehASBz
setItems(items); {1a%CsCM
setStartIndex(startIndex); SJ4[n.tPI
} a(-
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public PaginationSupport(List items, int U'8+YAgc
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totalCount, int pageSize, int startIndex){ ;Gf,$dbWn
setPageSize(pageSize); [k qx%4q)
setTotalCount(totalCount); 6Ap-J~4
setItems(items); z2:^Qg
setStartIndex(startIndex); A"Q6GM2;Io
} |Et8FR3[m
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publicList getItems(){ "`;$wA
return items; R0|dKKzS
} $2lrP]`>j.
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publicvoid setItems(List items){ (.Q.S[<Y
this.items = items; O2z{>\
} X)P;UVR0
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publicint getPageSize(){ Q7u/k$qN
return pageSize; %#5yC|o9Pn
} &z'NQ!uV
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publicvoid setPageSize(int pageSize){ V $'~2v{_
this.pageSize = pageSize; {,V .IDs8[
} of? hP1kl[
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publicint getTotalCount(){ ([vyY}43h
return totalCount; b8Bf,&:ys
} =v-qao7xCV
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publicvoid setTotalCount(int totalCount){ 6MsVV_/
if(totalCount > 0){ &d5n_:^
this.totalCount = totalCount; dXwfOC\\
int count = totalCount / SQ$|s%)oB
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pageSize; 'MF|(`
if(totalCount % pageSize > 0) $@WqM$
count++; 4gyC?#Ede
indexes = newint[count]; _SVIY@K|/
for(int i = 0; i < count; i++){ )(^L*
indexes = pageSize * :9nqQJ+~
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i; W>^WNo3YQ$
} g3fxf(iY(
}else{ Dm^Bk?#(
this.totalCount = 0; Ev%_8CO4e
} i\h"N K
} H]zi>;D
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publicint[] getIndexes(){ )R~l@QBN
return indexes; r2t|,%%N7
} __B`0t
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publicvoid setIndexes(int[] indexes){ '3<AzR2
this.indexes = indexes; Ah_,5Z@&R
} @^O+ulLJ,]
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publicint getStartIndex(){ zYCS K~-GW
return startIndex; 6}q8%[l|
} &1ZqC;
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publicvoid setStartIndex(int startIndex){ sWG_MEbu
if(totalCount <= 0) @2X{e7+D
this.startIndex = 0; ?QbxC,& i
elseif(startIndex >= totalCount) r2h{#2
this.startIndex = indexes Z?@oe-mz
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[indexes.length - 1]; p-qt?A
elseif(startIndex < 0) h?D>Dfeg%
this.startIndex = 0; J*%XtRio
else{ QDHTP|2e
this.startIndex = indexes $\9M6k'
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[startIndex / pageSize]; 9ZYT#h
} "/#=8_f
} y\C_HCU H
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publicint getNextIndex(){ >Q-"-X1
int nextIndex = getStartIndex() + 3$~oQC
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pageSize; Y3n6y+Uzk
if(nextIndex >= totalCount) ;WP%)Z
return getStartIndex(); CI8bHY$
else C1M @;
return nextIndex; >[qoNy;
} q+J;^u"E
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publicint getPreviousIndex(){ @5,Xr`]
int previousIndex = getStartIndex() - >"/Sa_w
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pageSize; -ld1o+'`v!
if(previousIndex < 0) u$MXO].Q
return0; Tw]].|^f-
else t/KH`
return previousIndex; sWGc1jC?.F
} |ZmWhkOX
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} 6E))4
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抽象业务类 J};=)xLX;
java代码: L
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/** 6^#@y|.
* Created on 2005-7-12 0<$t9:dq
*/ ?(2^lH~6h
package com.javaeye.common.business; L
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import java.io.Serializable; d>-k-X-[
import java.util.List; C9Xj)5k@R
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import org.hibernate.Criteria; c-".VF
import org.hibernate.HibernateException; 0NFYFd-50
import org.hibernate.Session; wxW\L!@
import org.hibernate.criterion.DetachedCriteria; 0~GtK8^B
import org.hibernate.criterion.Projections; @";zM&
import %7[Z/U=
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org.springframework.orm.hibernate3.HibernateCallback; _gn`Y(c$%
import .j l|?o
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org.springframework.orm.hibernate3.support.HibernateDaoS VqBb=1r%o7
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upport;
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import com.javaeye.common.util.PaginationSupport; e)):U
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public abstract class AbstractManager extends "+k^8ki
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HibernateDaoSupport { }MCJ$=5
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privateboolean cacheQueries = false; nAY'1!O i
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privateString queryCacheRegion; {6Qd,CX
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publicvoid setCacheQueries(boolean _7P#?:h
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cacheQueries){ 5FQtlB9F
this.cacheQueries = cacheQueries; S*9qpes-m|
} CTh!|mG
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publicvoid setQueryCacheRegion(String
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queryCacheRegion){ { 2\.
this.queryCacheRegion = i?D
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queryCacheRegion; Bkh1VAT
} V+- ]txu|
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publicvoid save(finalObject entity){ MbJ|6g99
getHibernateTemplate().save(entity); aZBb@~Y
} JVawWw0q
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publicvoid persist(finalObject entity){ nQ}$jOU&
getHibernateTemplate().save(entity); 1C]mxV=%
} ]46#u=y~3
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publicvoid update(finalObject entity){ 6
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getHibernateTemplate().update(entity); 9?L,DThQ
} j]5mzz~
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publicvoid delete(finalObject entity){ +%: /!T@@
getHibernateTemplate().delete(entity); q{E44
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} &>$+O>c ,
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publicObject load(finalClass entity, qrxn%#\XP
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finalSerializable id){ O\&[|sGY{
return getHibernateTemplate().load Yp(F}<f?
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(entity, id); I?Fv!5p
} 8{ooLdpX7
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publicObject get(finalClass entity, w0(1o_F7.
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finalSerializable id){ G>>TB{}
return getHibernateTemplate().get zvAUF8'_
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(entity, id); \#O}K
} >uR0Xs;V
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publicList findAll(finalClass entity){ j$ h>CZZ
return getHibernateTemplate().find("from *s1^s;LR
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" + entity.getName()); CYFi_6MFl
} BK;Gh0mp
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publicList findByNamedQuery(finalString 1
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namedQuery){ @B#\3WNt
return getHibernateTemplate pB0p?D)n
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().findByNamedQuery(namedQuery); Z\. n6
} .0]\a~x
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publicList findByNamedQuery(finalString query, JVxGS{Z
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finalObject parameter){ ;%W]b
return getHibernateTemplate 2*)2c[/0F
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().findByNamedQuery(query, parameter); 1r?hRJ:'
} !9p;%Ny`
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publicList findByNamedQuery(finalString query, b<bj5m4fz>
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finalObject[] parameters){ c0aXOG^
return getHibernateTemplate (<KFA,
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().findByNamedQuery(query, parameters); rZ#ZY
} -g\ ;B
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publicList find(finalString query){ o|G[/o2
return getHibernateTemplate().find ?%A9}"q]
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(query); L'L[Vpx
} n4sO#p)'
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publicList find(finalString query, finalObject Y!qn[,q8
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parameter){ i9koh3R\
return getHibernateTemplate().find Q5xQ5Le
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(query, parameter); 4..M *U
} l9t|@9
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public PaginationSupport findPageByCriteria <q.Q,_cW
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(final DetachedCriteria detachedCriteria){ 6m%#cP
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return findPageByCriteria %urd;h D
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); H@!]5 <:9
} b[KZJLZ)
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public PaginationSupport findPageByCriteria Xti.yQx\
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(final DetachedCriteria detachedCriteria, finalint `Kbf]"4q
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startIndex){ 9 2x)Pc^D
return findPageByCriteria Qo~|[]GE
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(detachedCriteria, PaginationSupport.PAGESIZE, WZM
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startIndex); wZfY~
} i__f%j`!W
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public PaginationSupport findPageByCriteria 6Ts[NXa
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(final DetachedCriteria detachedCriteria, finalint jwpahy;\WL
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pageSize, GTM@9^
finalint startIndex){ K7R!E,oPg
return(PaginationSupport) [}HS[($
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getHibernateTemplate().execute(new HibernateCallback(){ "5204I
publicObject doInHibernate y$+=>p|d.^
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(Session session)throws HibernateException { C8W_f( i~
Criteria criteria = bFhZSk)
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detachedCriteria.getExecutableCriteria(session); dVg'v7G&V(
int totalCount = *q"1I9zvT
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((Integer) criteria.setProjection(Projections.rowCount Y-lwS-Ii
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()).uniqueResult()).intValue(); ~)F_FS
criteria.setProjection Tm$8\c4V:*
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(null); +/
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List items = "~S2XcR[ E
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criteria.setFirstResult(startIndex).setMaxResults +IMt$}7[
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(pageSize).list(); LP !d|X
PaginationSupport ps = B2Rpd &[
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new PaginationSupport(items, totalCount, pageSize, R13V}yL
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startIndex); Qsw.429t
return ps; Vw3=jIQN:!
} wwv+s ~(0
}, true); 'y5H%I!
} nBLb1T
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public List findAllByCriteria(final 8
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DetachedCriteria detachedCriteria){ HYG1BfEaW
return(List) getHibernateTemplate 6Eus_aP
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().execute(new HibernateCallback(){ %%#bTyF
publicObject doInHibernate GXk
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(Session session)throws HibernateException { CMyz!jZ3
Criteria criteria = Bz|/TV?X(
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detachedCriteria.getExecutableCriteria(session); of
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return criteria.list(); tv Zq):c
} 4CtWEq
}, true); bvHQ #:}H
} Jw>na _FJ
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public int getCountByCriteria(final f@$kK?c?
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DetachedCriteria detachedCriteria){ ,b5vnW\
Integer count = (Integer) ]>ndFE6kl
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getHibernateTemplate().execute(new HibernateCallback(){ GctV
publicObject doInHibernate ?>I
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(Session session)throws HibernateException { L
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Criteria criteria = 9g'6zB
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detachedCriteria.getExecutableCriteria(session); ;g;1<?
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return g$vOWSI+
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criteria.setProjection(Projections.rowCount "zz b`T[8
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()).uniqueResult(); SSyARR+;c
} ,rF!o_7
}, true); }W(t>>
return count.intValue(); FFe{=H,=
} }f% Qk0^
} l8 $.k5X
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用户在web层构造查询条件detachedCriteria,和可选的 ,H<nNBv3M
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (
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PaginationSupport的实例ps。 rW_cLdh]#
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ps.getItems()得到已分页好的结果集 <^'IC9D]
ps.getIndexes()得到分页索引的数组 rusYNb1J
ps.getTotalCount()得到总结果数 52,'8`
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ps.getStartIndex()当前分页索引 p,uM)LD
ps.getNextIndex()下一页索引 ]scr@e
ps.getPreviousIndex()上一页索引 tp }Bz&V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g:U
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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 Ol>/^3a=
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一下代码重构了。 St>
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我把原本我的做法也提供出来供大家讨论吧: ,OP\^
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首先,为了实现分页查询,我封装了一个Page类: e 0Z2B2
java代码: r(_Fr#Qn
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/*Created on 2005-4-14*/ E8<,j})*
package org.flyware.util.page; Ox)_7A
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/** h uR ^l
* @author Joa U2~|AkL
* nrXKS&6
*/ r?^L/HGc
publicclass Page { H7<g5pv
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/** imply if the page has previous page */ [D?d~pB
privateboolean hasPrePage; v;}MHl
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/** imply if the page has next page */ f}ch1u>
privateboolean hasNextPage; k)8*d{ *
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/** the number of every page */ _G/uDP%
privateint everyPage; +Q[SddI
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/** the total page number */ 73{<;z}i
privateint totalPage; DiZv sc
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/** the number of current page */ Z *v`kl
privateint currentPage; Pi,86?
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/** the begin index of the records by the current RmOkb~
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query */ :x^e T
privateint beginIndex; ^?A>)?Sq
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/** The default constructor */ mQ<Vwx0
public Page(){ u%OLXb
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} SaRn>n\
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/** construct the page by everyPage g"g3|$#Ej|
* @param everyPage qK%#$JgqA
* */ 3J3wKw!`
public Page(int everyPage){ <u?\%iJ"
this.everyPage = everyPage; "1p,
r&}
} ws
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/** The whole constructor */ wX!0KxR/Z
public Page(boolean hasPrePage, boolean hasNextPage,
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int everyPage, int totalPage, a,n#E!zT?w
int currentPage, int beginIndex){ 9pk-#/ag
this.hasPrePage = hasPrePage; 3 [O+wVv
this.hasNextPage = hasNextPage; A+fXt`YNM
this.everyPage = everyPage; bY~V?yNgKM
this.totalPage = totalPage; vJX0c\e
this.currentPage = currentPage; _! ?a9
this.beginIndex = beginIndex; WP^wNi
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} $"6Gv
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/** i7&ay\+@
* @return L;6{0b58$
* Returns the beginIndex. 8LY^>.
*/ )vY )Mg
publicint getBeginIndex(){ Nkn2\w
return beginIndex; i
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} /U0,%
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/** :8]y*j
* @param beginIndex fW=eB'Sl
* The beginIndex to set. 02YmV%
*/ \9}DAM_
publicvoid setBeginIndex(int beginIndex){ `1lGAKv
this.beginIndex = beginIndex; >^ E*7Bfp
} R ^INl@(O
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/** K :>O X
* @return EQ>@K-R
* Returns the currentPage. BP1<:T'.q`
*/ N).'>
publicint getCurrentPage(){ w/9%C(w6
return currentPage; lnK#q.]
} \4O_@d`A
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/** bzECNi5^
* @param currentPage /*t H$\6*
* The currentPage to set. O-3a U!L
*/ OMBH[_
publicvoid setCurrentPage(int currentPage){ ;R$2+9
this.currentPage = currentPage; cNye@}$lu
} X3?RwN:P
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/** /-+hMYe
* @return Q07&7SH_
* Returns the everyPage. yI/ FD
*/ bL5u;iy)
publicint getEveryPage(){ 4zZ.v"laVM
return everyPage; Y+5aT(6O
} W>'(MB$3
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/** x0lAJaG
* @param everyPage xtK\-[n
* The everyPage to set. m ^w{:\p
*/ kM(m$Oo.
publicvoid setEveryPage(int everyPage){ F3L+X5D.yu
this.everyPage = everyPage; )_6W@s
} Kq(JHB+
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/**
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* @return Z*=$n_
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* Returns the hasNextPage. T wzpq1
*/ qqys`.
publicboolean getHasNextPage(){
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return hasNextPage; 9Q'[>P=1
} %pqB/
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/** )JJF}m=
* @param hasNextPage 6Cfsh<]b
* The hasNextPage to set. ?]o(cz
*/ p|@#IoA/e
publicvoid setHasNextPage(boolean hasNextPage){ Ys|SacWC
this.hasNextPage = hasNextPage; E'NS$,h
} /Z[HU{4
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/** DO( 3hIj
* @return {|B[[W\TN
* Returns the hasPrePage. }0iHf'~DH*
*/ JoZSp"R
publicboolean getHasPrePage(){ f>|<5zm#<
return hasPrePage; >]o>iOz;]
} UcH#J &r
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/** 6Nt/>[
* @param hasPrePage kt=&mq/B
* The hasPrePage to set. 1N<n)>X4
*/ \jmZt*c
publicvoid setHasPrePage(boolean hasPrePage){ SpYmgL?wJ
this.hasPrePage = hasPrePage; |o'r?"
} L27WD m^)
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/** *2rc Y
* @return Returns the totalPage. X*:,|
* !~vx|_$#
*/ B^/k`h6J
publicint getTotalPage(){ u?H.Z
return totalPage; B|,d
} xA`j:zn'j
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/** *M_^I)*L
* @param totalPage Uw!d;YQm
* The totalPage to set. B2a#:E,6
*/ fre5{=@
publicvoid setTotalPage(int totalPage){ /J&ks>St
this.totalPage = totalPage; gS@<sO$d>
} #dD0vYT&od
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} &fl RrJ
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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 (|rf>=B+H
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个PageUtil,负责对Page对象进行构造: K+XUC
java代码: 9%"`9j~H>
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/*Created on 2005-4-14*/ |lg jI!iK
package org.flyware.util.page; Q\T?t
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import org.apache.commons.logging.Log; xI~AZ:m
import org.apache.commons.logging.LogFactory; {K6Z.-.`
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/** j"aY\cLr t
* @author Joa ZS;V?]\(
* &/ED.K
*/ cofdDHXfQI
publicclass PageUtil { } .Z`
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privatestaticfinal Log logger = LogFactory.getLog RA[%8Rh)
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(PageUtil.class); 1q3"qYH
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/** Xt$P!~Lu
* Use the origin page to create a new page @"1Z;.S8V
* @param page '`.-75T
* @param totalRecords /<IWdy]$3
* @return <hiv8/)?
*/ 19c_=$mV
publicstatic Page createPage(Page page, int QKB+mjMH#x
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totalRecords){ ,aGIq. *v
return createPage(page.getEveryPage(), *w O~RnP
}LKD9U5;8
page.getCurrentPage(), totalRecords); #+V4<o
} 9+PAyI#w
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/** OKK Ko`RN
* the basic page utils not including exception OFyy!r@?
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handler wWfj#IB;R
* @param everyPage }r,xx{.u7
* @param currentPage G.~Q2O#T
* @param totalRecords 3S]QIZ1
* @return page w0oTV;yh
*/ *($,ay$&H
publicstatic Page createPage(int everyPage, int 3nc\6v%
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currentPage, int totalRecords){ Skg/iH"(
everyPage = getEveryPage(everyPage); v
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currentPage = getCurrentPage(currentPage); fpf,gb8[$n
int beginIndex = getBeginIndex(everyPage, njg0MZBqA
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currentPage); ,>7dIJqzw
int totalPage = getTotalPage(everyPage, Ky,upU
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totalRecords); 8h@L_*Kr
boolean hasNextPage = hasNextPage(currentPage, fW+"Kuw
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totalPage); ?O#,{ZZf=
boolean hasPrePage = hasPrePage(currentPage); GdNhEv
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returnnew Page(hasPrePage, hasNextPage, `'<$N<!
everyPage, totalPage, Fj~suZ`
currentPage, .BBJhXtrdu
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beginIndex); av|T|J/(
} /7Pqy2sgE
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privatestaticint getEveryPage(int everyPage){ +~iiy;i(
return everyPage == 0 ? 10 : everyPage; 'G>XI;g
} M(K7xx+G
*->*p35
privatestaticint getCurrentPage(int currentPage){ JN+7oh]u
return currentPage == 0 ? 1 : currentPage; K;sC#9m
} z{\tn.67
;5[OS8
privatestaticint getBeginIndex(int everyPage, int { m~)~/z?
W-#DEU 7_
currentPage){ Q~Mkf&s
return(currentPage - 1) * everyPage; u%:`r*r
} O{~Xp!QQt
T5zS3O
privatestaticint getTotalPage(int everyPage, int #UL75
pMHl<HH
totalRecords){ \L~^c1s3r
int totalPage = 0; xO>z
)3A
c YgJ}(>}
if(totalRecords % everyPage == 0) Os$E,4,py
totalPage = totalRecords / everyPage; `b8nz 7
else R3_OCM_*
totalPage = totalRecords / everyPage + 1 ; qKd ="PR}
99ZWB
return totalPage; >xS({1A}
} lkTA"8d
Z8bg5%
privatestaticboolean hasPrePage(int currentPage){ c:0n/DC
return currentPage == 1 ? false : true; 7,p.M)t)
} I1':&l^O
grgs r_)[
privatestaticboolean hasNextPage(int currentPage, )SJM:E
E7\K{]
int totalPage){ M KW~rrR
return currentPage == totalPage || totalPage == 0*5Jq#5
uCB9;+ Hjw
0 ? false : true; `9[n5-t
} K)>F03=uE
\ . #Y
: H;S"D
} ~8nR3ki
~%=%5}
vi^YtA
ohKoX$|p~
`WL3aI":
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。 .tG3g:
WM|G/'q
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 @H#Fzoo.
vb>F)po1}
做法如下: pp(09y`]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 GNv{Ij<
}hg=#*
的信息,和一个结果集List: XV%R Mr6
java代码: KO8{eT9d
80lhhqRC
aQL0Sj:,
/*Created on 2005-6-13*/ E`JW4)AH
package com.adt.bo; HoAg8siQ
k;cX,*DIn
import java.util.List; zuN(~>YH
._tEDY/1m
import org.flyware.util.page.Page; QObVJg,GD
vv,<#4d
/** +8Q @R)3
* @author Joa J61%a,es
*/ BZ.l[LMp
publicclass Result { ej_u):G*
\8C<nh
private Page page; !c)F;
i@rUZYF
private List content; )=}qAVO8
vd#)+
/** $*X?]?
* The default constructor W*S4gPGM
*/ AP>n-Z|
public Result(){ Brs6RkRf
super(); <& PU%^Ha
} {jYVA~.|Z
R[\1Kk(Zo
/** w?u3e+
* The constructor using fields g#74c'+
* t{},Th
* @param page WxYEu+_
* @param content _Cz98VqRk
*/ &8i$`6wY
public Result(Page page, List content){ FXT^r3
this.page = page; .zdaY,
U
this.content = content; q M_c-^F
} 1ED7.#g
%-fXa2
/** egA*x*8
* @return Returns the content. Xa>'DO2
*/ HTiLA%%6
publicList getContent(){ V0A> +
return content; cz/E
} ML|?H1m>
:F6dXW
/** b4^O=
* @return Returns the page. |H5GWZ
O{^
*/ pe,y'w{
public Page getPage(){ M __S)
return page; ^NX;zc
} e%ro7~
yy/'B:g
/** 1(T2:N(M-A
* @param content Tw$tE:
* The content to set. V[%IU'{:
*/ .?APDr"QQH
public void setContent(List content){ (FGy"o%TP'
this.content = content; l v:GiA"X
} iu<Tv,{8
Kp7)my
/** W.{+0xx
* @param page O\cc=7
* The page to set. 8*?H~q~
*/ %$b}o7U"s
publicvoid setPage(Page page){ eV(.\Lj
this.page = page; Q~f]?a`
} on8$Kc
} C%<Dq0j
5ad@}7&
5G'2 Wby'#
tkptm%I_
;m|N9'
2. 编写业务逻辑接口,并实现它(UserManager, gGCr~.5
v h)CB8
UserManagerImpl) Av n-Ug
java代码: `%Kj+^|DS
YVF@v-v-,
D` cy.},L
/*Created on 2005-7-15*/ KMfIp:~
package com.adt.service; @Kt!uKrI
/8:e|
]
import net.sf.hibernate.HibernateException; v#g:]T
P^Og(F8;
import org.flyware.util.page.Page; e 5(|9*t
&'/PEOu&}G
import com.adt.bo.Result; O['[_1n_u]
leSBR,C
/** uj%]+Llxv
* @author Joa d5
]-{+V+
*/ OiC|~8
publicinterface UserManager { w0yzC0yBk
k'F*uS
public Result listUser(Page page)throws 07(LLhk@d
g=v'[JPd
HibernateException; 0RCp
ZV5IZ&V!
} .;bU["fn)
})mD{c/
lt5Knz2G,Z
l%i*.b(
x>K,{{B)X
java代码: $i3`cX)g
.hf%L1N%F
)`|`PB
/*Created on 2005-7-15*/ h{~GzrL*
package com.adt.service.impl; vgNrHq&2q
z+0#H39 &
import java.util.List; j:48l[;ed
1v|0&{lB
import net.sf.hibernate.HibernateException; 1!+0]_8K
6khm@}}
import org.flyware.util.page.Page; Y!(w. G
import org.flyware.util.page.PageUtil; fpzEh}:H\
JNvgUb'U
import com.adt.bo.Result; TEK#AR
import com.adt.dao.UserDAO; %vG;'_gMB
import com.adt.exception.ObjectNotFoundException; `09[25?
import com.adt.service.UserManager; >N~jlr |
CX{M@x3m
/** H\<PGC"_Y
* @author Joa WdJeh:h
*/ ?^8.Sa{
publicclass UserManagerImpl implements UserManager { op&j4R
*`bES V
:
private UserDAO userDAO; _$}@hD*R~
g'-hSV/@}@
/** 0o.h{BN
* @param userDAO The userDAO to set. +&1#ob"6lq
*/ $iH
publicvoid setUserDAO(UserDAO userDAO){ %~Ymb&ugg
this.userDAO = userDAO; s2+_`Ogg
} 0V2~
WL\*g] K4
/* (non-Javadoc) $nf
%<Q
* @see com.adt.service.UserManager#listUser `;Fs
D/2;b;-
(org.flyware.util.page.Page) qV$0 ";d
*/ aMgg[g9>t
public Result listUser(Page page)throws b%j4W)Z
Qeq=4Nq
HibernateException, ObjectNotFoundException { ?/Aql_?3
int totalRecords = userDAO.getUserCount(); AX{yfL
if(totalRecords == 0) eX^ F^(
throw new ObjectNotFoundException cgQ2Wo7tCq
|'L$ogt6
("userNotExist"); o|VM{5
page = PageUtil.createPage(page, totalRecords); *+ O
List users = userDAO.getUserByPage(page); c
8|&Q
returnnew Result(page, users); \AD|;tA\vE
} A6Wtzt2i
z&|sks7
} 1lv.@-
6"bdbV=t
s:sk`~2<gd
c/G^}d%
QnH~'
k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 SYv5{bff =
vqwSOh|P9
询,接下来编写UserDAO的代码: $0;Dk,
3. UserDAO 和 UserDAOImpl: ~uO9>(?D
java代码: *3y:Wv T>
h{VGhkU9f
Rd+`b
/*Created on 2005-7-15*/ u|&a!tOf2
package com.adt.dao; [PU0!W;
G^w:c]
import java.util.List; #xxs^Kbqa#
r1xhplHH@
import org.flyware.util.page.Page; OQsF$%*
qH*Fv:qnM
import net.sf.hibernate.HibernateException; 9jt+PII
=a./HCF
/** ->U9u lTC
* @author Joa nOUF<DNQ
*/ Y[alOJ
publicinterface UserDAO extends BaseDAO { r(/+-
t
'sTMUPg`
publicList getUserByName(String name)throws #j${R={
| D,->k
HibernateException; W&0KO-}ot
Ba]^0Y
u
publicint getUserCount()throws HibernateException; $r=tOD4;
ioS(;2F
publicList getUserByPage(Page page)throws $<s
3;>t
HFrwf{J
HibernateException; .uu[MzMIu
Q"sszz
} x1R<oB|
qFYM2
L)j<;{J/Q0
:B]yreg
\ POQeZ
java代码: \L{V|}"X
YhNO{4D
B1Cu?k);.
/*Created on 2005-7-15*/ +yo1&b R/
package com.adt.dao.impl; :f5"w+
h1.<\GO
import java.util.List; C{8(ew
U/3<p8
import org.flyware.util.page.Page; lcYjwA
-yP_S~\n
import net.sf.hibernate.HibernateException; &)v}oHy,m
import net.sf.hibernate.Query; *3]_Huw<
j$Z:S~*
import com.adt.dao.UserDAO; aJ^RY5
TQg~I/
/** -{rUE +
* @author Joa \RDS~u\d
*/
c
1o8
public class UserDAOImpl extends BaseDAOHibernateImpl 0JM`*f%n
y$C\b\hM
implements UserDAO { DZE@C^0%
_[t:Vme}v
/* (non-Javadoc) ZF~@a+o
* @see com.adt.dao.UserDAO#getUserByName !{%BfZX<&
@ UCr`>
(java.lang.String) ;2jH;$HZ
*/ FEwPLViso
publicList getUserByName(String name)throws pW4$$2S?9
HS
>B\Ip"
HibernateException { !)$e+o^W
String querySentence = "FROM user in class hWD%_"yhd
-h8@B+
com.adt.po.User WHERE user.name=:name"; Cu&y',ee~
Query query = getSession().createQuery WCUaXvw
d !=AS
(querySentence); G3_HX<|f*
query.setParameter("name", name); fobnK~2
return query.list(); yHYK,3/C,
} $~5ax8u&!#
BOdd~f%&tn
/* (non-Javadoc) 5e}adHjM
* @see com.adt.dao.UserDAO#getUserCount() +nU=)x?38
*/ d.Ep#4
publicint getUserCount()throws HibernateException { >7,?X_:A-1
int count = 0; g?E8zf `
String querySentence = "SELECT count(*) FROM 8$`$24Wx
5/YGu=,
user in class com.adt.po.User"; z,xGjSP
Query query = getSession().createQuery L~|_C Rw
92XG|CWX
(querySentence); JpE7"Z"~MS
count = ((Integer)query.iterate().next SQs+4YJ
#sM`>KG6T1
()).intValue(); ]@{l<ExP
return count; I_\?w SNGM
} buKSZ
,xI
FF-[0
/* (non-Javadoc) tE WolO[\
* @see com.adt.dao.UserDAO#getUserByPage $|m'~AmI
K( r@JW
(org.flyware.util.page.Page) %sCG}?
y
*/ hg2UZ%
Y
publicList getUserByPage(Page page)throws 9 iV_
zmhL[1qj
HibernateException { YHzP/&0
String querySentence = "FROM user in class TpcJ1*t
kX%vTl7F
com.adt.po.User"; i5cK5MaD
Query query = getSession().createQuery 3/V0w|ZgD
[*U.bRs
(querySentence); [\-)c[/
query.setFirstResult(page.getBeginIndex()) [JYy
.setMaxResults(page.getEveryPage()); B&m6N,
return query.list(); ~J HEr48
} qs{wrem
GBY{O2!3u
} mJZB@m u?
MU:q`DRr
q.VZ P
S!66t?vHB
K-[;w$np0
至此,一个完整的分页程序完成。前台的只需要调用 qSt\ 6~
vj9'5]!~q
userManager.listUser(page)即可得到一个Page对象和结果集对象 e$7KMH=
Je4hQJ<h
的综合体,而传入的参数page对象则可以由前台传入,如果用 +GncQs
y
{F;"m&3Lt
webwork,甚至可以直接在配置文件中指定。 .d6b?t
&v#pS!UO j
下面给出一个webwork调用示例: ?[;>1+D
java代码: Tvt(nWn(H1
o8Yq3N +
T:SqENV
/*Created on 2005-6-17*/ ;3XOk+
package com.adt.action.user; .}Eckqkp
3&6sQ-}*
import java.util.List; CEAmb[h
|
{Q}:_/q
import org.apache.commons.logging.Log; tz5\O}
import org.apache.commons.logging.LogFactory; md `=2l
import org.flyware.util.page.Page; p-xG&CU
+j %y#_~
import com.adt.bo.Result; tUt_Q;%yC
import com.adt.service.UserService; 5O;D\M{>
import com.opensymphony.xwork.Action; H@b4(6
4'TssRot@h
/** 51tZ:-1!
* @author Joa v#EFklOP
*/ R3>c\mA
publicclass ListUser implementsAction{ qeb} ~FL"o
G[6i\Et
privatestaticfinal Log logger = LogFactory.getLog O`5h jq#
3 .K #,
(ListUser.class); vqZBDQ0
WrS>^\:
private UserService userService; ?L0 |$#Iw
z,bK.KFSs
private Page page; mZG n:f}=
m>RtKCtP
privateList users; WZTAXOw
j+rY
/* !^o{}*]Pi
* (non-Javadoc) 9kB R /{
* 7dv!
* @see com.opensymphony.xwork.Action#execute() x6^Y&,y9kU
*/ !K0 U..
publicString execute()throwsException{ )%PMDG|
Result result = userService.listUser(page); wWSo+40
page = result.getPage(); %~} ,N
users = result.getContent(); !8D>Bczq)
return SUCCESS; 97qf3^gGd
} -+M360
Ql%B=vgKL
/** <LzxnTx=
* @return Returns the page. KMK8jJ
*/ E-($Xc
public Page getPage(){ 3,K\ZUU.,
return page; 9 )!}
} Fq_>}k@fI
tRO=k34
/** h"/'H)G7_&
* @return Returns the users. l~w^I|M^C
*/ IC (:RtJ
publicList getUsers(){ k5J18S
return users; ^#Mp@HK
} QqRF?%7q"q
j S[#R_
/** "}#%h&,
* @param page (wu ciKQ
* The page to set. Z4c'1-lh
*/ Vo+.s#wN`h
publicvoid setPage(Page page){ RwYFBc
this.page = page; %l14K_
} wu><a!3`=o
ZNM9@;7
/** ;']u}Nh
* @param users =[&+R9s
* The users to set. ExSM=
*/ ^1vKhO+p$
publicvoid setUsers(List users){ 7(uz*~Z?`0
this.users = users; _hJdC|/
} MG~Z)+g=y
_p5#`-%mM
/** *9uNM@7&0
* @param userService _P!b0x~\
* The userService to set. zi3v,Kq
*/ L\UGC%]9
publicvoid setUserService(UserService userService){ bmK
this.userService = userService; hczDu8
} ^<-)rzTI
} @eeI4Jz
/9&!u )+
Du65>O
{9-9!jN{"
O39
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, fM7B<eB
:aomDK*
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 D!!
B4zt
`B4Ilh"d
么只需要: `4snTM!v&
java代码: (]T[n={Y
>l><d!hw
,[6Rmsk
<?xml version="1.0"?> Sn4xv2/
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork bGL} nPo
j5" L
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,Yx<"2 W
8s2y!pn7Q
1.0.dtd"> _u^3uzu
u"(NN9s
<xwork> )^ZC'[93
3<+ZA-2
<package name="user" extends="webwork- >
^zNKgSQ
l0`bseN<
interceptors"> @vyEN.K%mm
3N-
'{c6]U
<!-- The default interceptor stack name NfPWcK[
Z!~_#_Ugl
--> KJ32L
<default-interceptor-ref ,$/Ld76U
97\K ]Tr
name="myDefaultWebStack"/> {*F
=&D
aVK,(j9u
<action name="listUser" RV_I&HD!
<=GZm}/]N
class="com.adt.action.user.ListUser"> k<Gmb~Tg1
<param 4gC(zJ
{[tmz;C
name="page.everyPage">10</param> L~{(9J'(
<result #<"od '{U
Qt{){uE
name="success">/user/user_list.jsp</result> i6k6l%
</action> au+Jz_$)
|yO%w #
</package> T=u"y;&L
WwTl|wgvyI
</xwork> (|Gwg \r
gAorb\iJ
^gx~{9`RR
4]m{^z`1
CF','gPnc
b<4nljbx
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 mOh?cjOi
"GZ}+K*GG
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。 1c#\CO1l
KCbJ^Rln
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K/Yeh<_&
f!yl&ulKU
~K #92
)#M$ov
}"WovU{*s
我写的一个用于分页的类,用了泛型了,hoho //|B?4kk
mxF+Fp~
java代码: lMu9Dp
~<<32t'S:
b3[[ Ah-
package com.intokr.util; v{|y,h&]a
\8<[P(!3
import java.util.List; q?mpvpLG
@d~]3T
/** 0aY\(@
* 用于分页的类<br> GqsV6kH
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +u=VO#IA#
* *&Iv Eu
* @version 0.01 wT- -i@@
* @author cheng ]!^wB 3j
*/ p<'pqf
public class Paginator<E> { j*|0#q;e6
privateint count = 0; // 总记录数 s?m_zJh
privateint p = 1; // 页编号 xg,
9~f[
privateint num = 20; // 每页的记录数 xLFMC?I
privateList<E> results = null; // 结果 FIfLDT+ Wh
c-&Q_lB
/** hM!g6\ w
* 结果总数 "O9n|B
*/ w@R" g%k-
publicint getCount(){ $PRd'YdL/
return count; Q%q;=a
} D`[@7$t
n(# yGzq
publicvoid setCount(int count){ V >eG\
this.count = count; =to.Oa RR
} ewn\'RLZ"@
9eHqOmz
/** jf1GYwuW*
* 本结果所在的页码,从1开始 P(I%9
* g.!k>_g`
* @return Returns the pageNo. 0Cf'\2
*/ /SM 7t_
publicint getP(){ cy?#LS
return p; >#&2 5,Q
} G?LC!9MB
_]ZlGq!L
/** ztHx)
!
* if(p<=0) p=1 W+8s>
* 9S9j
* @param p tj*0Y-F~
*/ /DHV-L
publicvoid setP(int p){ Iy;"ht6
if(p <= 0) /3hY[#e
p = 1; c+z [4"rYL
this.p = p; [+W<;iep
} Yc6.v8a
j-"34
/** f>Ua 7!b
* 每页记录数量 iyR"O1]
*/ H{i|?a)
publicint getNum(){ {0a\<l
return num; HrZX~JnTmf
} HEc.3
OJA_OqVp$K
/** '`<Fys&:
* if(num<1) num=1 w8$>
2
*/ | X#!5u
publicvoid setNum(int num){ 9(!AKKrr;
if(num < 1) `jOk6;Z[
num = 1; FVL{KNW~i
this.num = num; kmu`sk"
} +03/A`PKrB
B1U!*yzG6
/** OR
$i,N|
* 获得总页数 R:Ih#2R
*/ 2T?Y
publicint getPageNum(){ !kb:g]X
return(count - 1) / num + 1; I][&*V1
} Np$&8v+en
8*#$3e
/** [iO8R-N8d
* 获得本页的开始编号,为 (p-1)*num+1 PrfG
*/ 0&CXR=U5
publicint getStart(){ 3 4%B0
return(p - 1) * num + 1; ?GhMGpdMq
} CDuA2e
aMHC+R1X
/** @K*W3&