Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Rn^N+3o'M
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 HOI`F3#XI
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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 kR|DzB7
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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 ;iI2K/ 3
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。 8{^GC(W{]
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分页支持类: Z`h_oK#y15
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java代码: dufHd
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package com.javaeye.common.util; X~VZ61vNu
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import java.util.List; L.&Vi"M <@
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publicclass PaginationSupport { ~x#-#nuh"
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; QLLVOJi
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privateList items; z>#$#:Z4
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privateint totalCount; xGQ:7g+qu
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privateint[] indexes = newint[0]; H zK=UcD
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privateint startIndex = 0; w0OK.fj
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public PaginationSupport(List items, int a'.=.eDQ
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totalCount){ ~oyPmIcb
setPageSize(PAGESIZE); W|
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setTotalCount(totalCount); m#(x D~V
setItems(items); D#(L@{vC
setStartIndex(0); z@LP9+?dE
} #.K&]OV/88
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public PaginationSupport(List items, int U}5KAi 9Z
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totalCount, int startIndex){ eNKdub
setPageSize(PAGESIZE); hRiGW_t
setTotalCount(totalCount); qt)mUq;>
setItems(items); sMo%Ayes
setStartIndex(startIndex); m=y)i]=1
} ?|F;x"
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public PaginationSupport(List items, int je0 ?iovY
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totalCount, int pageSize, int startIndex){ 6H9]]Unju
setPageSize(pageSize); [IW7]Fv<F
setTotalCount(totalCount); B9 {DO
setItems(items); }6(:OB?
setStartIndex(startIndex); p`ZGV97
} t)ry)[Dxv
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publicList getItems(){ cE#Y,-f
return items; s;)tLJ!
} ;<Q_4
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publicvoid setItems(List items){ 7tnzgtal
this.items = items; aesFv)5DK
} BF#e=p
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publicint getPageSize(){ Yf9L~K
return pageSize; B) iJH
} -4a&R=%p
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publicvoid setPageSize(int pageSize){ tt91)^GdYa
this.pageSize = pageSize; od|.E$B
} XP1_{\
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publicint getTotalCount(){ 9t gkAU`
return totalCount; !r,drb
} (/BkwbJyE
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publicvoid setTotalCount(int totalCount){ D~,R@7
if(totalCount > 0){ <>GyG-q
this.totalCount = totalCount;
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int count = totalCount / 60$
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pageSize; >TJ$Z3
if(totalCount % pageSize > 0) vUNE!j
count++; pu#<qD*w
indexes = newint[count]; 2HNS|GHb&
for(int i = 0; i < count; i++){ Lr &tpB<
indexes = pageSize * ]y$C6iUY*
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i; f#+ h_1#
} /+7L`KPD
}else{ _69\#YvCG
this.totalCount = 0; ivk|-C'\
} 5sUnEHN
} =Ch#pLmH
}Z=Qy;zk
publicint[] getIndexes(){ pq`MO
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return indexes; oPV"JGa/B4
} .:/@<V+K
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publicvoid setIndexes(int[] indexes){ ]QQ"7_+
this.indexes = indexes; ^m9cEl^:nQ
} 4 n(
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publicint getStartIndex(){ T@XiG:b7
return startIndex; D%btlw?{
} wOP}SMn
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publicvoid setStartIndex(int startIndex){ PGDlSB^O
if(totalCount <= 0) k[m-"I%ZFX
this.startIndex = 0; #Ba'k6b
elseif(startIndex >= totalCount) 3@JwL{C
this.startIndex = indexes j.*}W4`Q_
G_@H:4$3
[indexes.length - 1]; \~>#<@h
elseif(startIndex < 0) UK/k?0
this.startIndex = 0; ;'kH<Iq
else{ d0d2QRX
this.startIndex = indexes YVi]f2F%
AnQRSB (
[startIndex / pageSize]; #e[5O|V~
} P[~a'u
} MaM7u:kD#
*,u{~(thR
publicint getNextIndex(){ ZhU2z*qN#
int nextIndex = getStartIndex() + }^t?v*kcA
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pageSize; N 2\,6 <
if(nextIndex >= totalCount) 1^mO"nX
return getStartIndex(); l0f6L xfz
else $I%]jAh6
return nextIndex; I nk76-
} H{If\B%1t
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publicint getPreviousIndex(){ fQdQ[
int previousIndex = getStartIndex() - .'M]cN~
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pageSize; \uH;ng|m
if(previousIndex < 0) Rh|&{Tf
return0; e"Z~%,^A
else T^ -RP
return previousIndex; ;S/fe(C
} .W\Fa2}%av
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} +9t@eHJT1
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抽象业务类 B(hNBq7
java代码: |dO1w.x/
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/** e5dw q
* Created on 2005-7-12 w$_ooQ(_;Q
*/ rBaK$Ut
package com.javaeye.common.business; 6k-]2,\#
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import java.io.Serializable; \VW.>@s~
import java.util.List; g_`8K,6ln
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import org.hibernate.Criteria; \I>,j,c
import org.hibernate.HibernateException; YB[P`Muj
import org.hibernate.Session; LS;kq',
import org.hibernate.criterion.DetachedCriteria; Y) Z>Bi
import org.hibernate.criterion.Projections; };|'8'5
import *ZHk^d:
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org.springframework.orm.hibernate3.HibernateCallback; 7ORwDR,`5
import B; ~T|ex u
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org.springframework.orm.hibernate3.support.HibernateDaoS fE >FT9c
`#~@f!';
upport; 7J)-WXk
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import com.javaeye.common.util.PaginationSupport; =d9%ce
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public abstract class AbstractManager extends fYpy5vc-dm
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HibernateDaoSupport { 8I*fPf
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privateboolean cacheQueries = false; y<Z8+/f`f
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privateString queryCacheRegion; U`D"L4},.
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publicvoid setCacheQueries(boolean R6ywc"xE
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cacheQueries){ Zscmc;G
this.cacheQueries = cacheQueries; L_/.b%0)
} Mb-C DPT
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publicvoid setQueryCacheRegion(String 3N?uY2
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queryCacheRegion){ Yk }zN_v
this.queryCacheRegion = Rzz*[H
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queryCacheRegion; kj>XKZL10
} ?P}7AF
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publicvoid save(finalObject entity){ lgU7jn
getHibernateTemplate().save(entity); H}A67J9x
} Oa{M9d,l
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publicvoid persist(finalObject entity){ I\":L
getHibernateTemplate().save(entity); \;4RD$J
} RP6QS )|
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publicvoid update(finalObject entity){ WKP=[o^
getHibernateTemplate().update(entity); iidK}<o
} =*t)@bn
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publicvoid delete(finalObject entity){ iYFM@ta
getHibernateTemplate().delete(entity); VPK)HzPG,
} ee6Zm+.B
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publicObject load(finalClass entity, S-My6'ar
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finalSerializable id){ By%aTuV$
return getHibernateTemplate().load M>-x\[n+
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(entity, id); hD
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} "zfy_h
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publicObject get(finalClass entity, !s5 _JO
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finalSerializable id){ 1--5ok
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return getHibernateTemplate().get 21W>}I"0?
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(entity, id); hCM+=]z"
} J-b
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publicList findAll(finalClass entity){ lRn>/7sg$
return getHibernateTemplate().find("from F@[l&`7
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" + entity.getName()); %-> X$,Q
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} T=9+
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publicList findByNamedQuery(finalString H&l/o
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namedQuery){ Lk4gjs,V
return getHibernateTemplate ~#Vrf0w/
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().findByNamedQuery(namedQuery); o#CNr5/
} =#^\9|?$
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publicList findByNamedQuery(finalString query, 9/`T]s"
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finalObject parameter){ uK1DC i
return getHibernateTemplate \K55|3~R
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().findByNamedQuery(query, parameter); Sw%^&*J
} C,&r7
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publicList findByNamedQuery(finalString query, U%_BgLwy%
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finalObject[] parameters){ V-IXtQR
return getHibernateTemplate G,3.'S,7
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().findByNamedQuery(query, parameters); LS
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} m?0caLw<
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publicList find(finalString query){ CN+[|Mz*p
return getHibernateTemplate().find "K;f[&xO,o
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(query); Sjv_% C$
} BRyrdt*_e
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publicList find(finalString query, finalObject IZn|1X?}\s
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parameter){ )lwxFP;
return getHibernateTemplate().find [2ez" 4e
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(query, parameter); "w7wd5h
} C/_Z9LL?F
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public PaginationSupport findPageByCriteria rvouE:
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(final DetachedCriteria detachedCriteria){ b"k1N9
return findPageByCriteria 4c0 =\v
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Xw)W6H|
} C;>!SRCp
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public PaginationSupport findPageByCriteria =^3 Z
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(final DetachedCriteria detachedCriteria, finalint c'O"</
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startIndex){ *sz:c3{_
return findPageByCriteria |$
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(detachedCriteria, PaginationSupport.PAGESIZE, Z}$wvd
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startIndex); (J}tCqP
} OXDEU.
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public PaginationSupport findPageByCriteria ;iq H:wO
{ 0?^ $R8j
(final DetachedCriteria detachedCriteria, finalint \3q Z0
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pageSize, !A":L0[7n
finalint startIndex){ <Ukeq0
return(PaginationSupport) Smg z}
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getHibernateTemplate().execute(new HibernateCallback(){ `"Lk@
publicObject doInHibernate o=C:=
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(Session session)throws HibernateException { q[}W&t,
Criteria criteria = v-(dh5e`
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detachedCriteria.getExecutableCriteria(session); uSQRI9/ir2
int totalCount = @;;3B
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((Integer) criteria.setProjection(Projections.rowCount pmfL}Dn
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()).uniqueResult()).intValue(); c'md)nD2M
criteria.setProjection H'a6]
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(null); [jnA? Ge:
List items = SR>(GQ,m0;
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criteria.setFirstResult(startIndex).setMaxResults 9w!PA-) L
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(pageSize).list(); Fe L !%z
PaginationSupport ps = FQ_a=v
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new PaginationSupport(items, totalCount, pageSize, tZ>'tE
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startIndex); ,8@q2a/
return ps; |Ml~_m
} XcFu:B
}, true); z?<Xx?Kk
} lK Ry4~O
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public List findAllByCriteria(final ech1{v\B|
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DetachedCriteria detachedCriteria){ j6GR-WQ]t
return(List) getHibernateTemplate ak_n
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().execute(new HibernateCallback(){ 7hlzuZob+y
publicObject doInHibernate X? 7s
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(Session session)throws HibernateException { eWOZC(I*z
Criteria criteria = * `3+x
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detachedCriteria.getExecutableCriteria(session); T_ j0*A$
return criteria.list(); /lLG|aAe
} ~Dbu;cqR@
}, true); }hA)p:
} ("s!t?!&YS
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public int getCountByCriteria(final V~7Oa2'#B
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DetachedCriteria detachedCriteria){ g?rK&UTU
Integer count = (Integer) Ri/D>[
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getHibernateTemplate().execute(new HibernateCallback(){ 9Xe|*bT
publicObject doInHibernate 9~v#]Q}Z}4
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(Session session)throws HibernateException { Dco3`4pl
Criteria criteria = i4<n#]1!t
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detachedCriteria.getExecutableCriteria(session); lm8<0*;,
return ({<qs}H"
^f] 9^U{
criteria.setProjection(Projections.rowCount _^h?JTU^
^S:I38gR#q
()).uniqueResult(); QSx4M
} u}-)ywX
}, true); v*&WqVg
return count.intValue(); Va$JfWef
} s+9b.
} 0Wb3M"#9<
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用户在web层构造查询条件detachedCriteria,和可选的 ejpSbVJ
Bgs,6:
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~}Z'/zCZf
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PaginationSupport的实例ps。 2{01i)2 y
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ps.getItems()得到已分页好的结果集 m }\L i]
ps.getIndexes()得到分页索引的数组 MC_i"P6a
ps.getTotalCount()得到总结果数 eY\!}) 5
ps.getStartIndex()当前分页索引 5N[H@%>QO
ps.getNextIndex()下一页索引 ,-)ww:
ps.getPreviousIndex()上一页索引 PG*FIRDb
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 y^:6D(SR
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 }-PV%MNud
8 O.5ML{
一下代码重构了。 y*j8OA.S
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我把原本我的做法也提供出来供大家讨论吧: 89fl\18%
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首先,为了实现分页查询,我封装了一个Page类: :i]g+</
java代码: An=Q`Uxt/
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/*Created on 2005-4-14*/ ]*\<k
package org.flyware.util.page; fVxRK\a\\
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/** C<hb{$@
* @author Joa Ts3(,Y
* `bEum3l\6]
*/ -P$E)5?^
publicclass Page { fZt3cE\
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/** imply if the page has previous page */ hP=z<&zb/
privateboolean hasPrePage; &>z}u&oF
l&m'?.gf
/** imply if the page has next page */ 1a;&&!X
privateboolean hasNextPage; ppPzI,
)4bZ;'B5
/** the number of every page */ {#%;Hq P
privateint everyPage; et :v4^*f
6T=zHFf~
/** the total page number */ {y7,n
privateint totalPage; ii]'XBSVd
fSzX /r
/** the number of current page */ 21G:!t4/?n
privateint currentPage; C6wlRvWn
-~imxPmZ
/** the begin index of the records by the current RYKV?f#[H
eO=!(
query */ P%xz"l i
privateint beginIndex; `-)Fx<e
o)IcAqN$H
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/** The default constructor */ h}$]3/5H
public Page(){ &<%U7?{~
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} 7`6JK
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/** construct the page by everyPage POvpaPAZ<
* @param everyPage kEs=N(
* */ *oz=k
public Page(int everyPage){ 0!,)7
this.everyPage = everyPage; .j 0]hn]
} R7!^ M
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/** The whole constructor */ 7<%Rx19L*
public Page(boolean hasPrePage, boolean hasNextPage, 9wC:8@`6E
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2F#R;B#2
int everyPage, int totalPage, 7c Gq.U
int currentPage, int beginIndex){ &tw
this.hasPrePage = hasPrePage; =rDIU&0Y
this.hasNextPage = hasNextPage; u(|k/~\
this.everyPage = everyPage; =.Q|gZ
this.totalPage = totalPage; zwKm;;v8
this.currentPage = currentPage; "RJf2~(ZX
this.beginIndex = beginIndex; ))>)qav
} xj!_]XJ^w
dSBW&-p
/** Ctxx.MM
* @return DeTZl+qm1E
* Returns the beginIndex. SAGLLk07G
*/ 8M;G@ Q80
publicint getBeginIndex(){ |_;Vb
return beginIndex; C&ivjFf
} v`$9;9
WtTwY8HC
/** P'6(HT>F?
* @param beginIndex !S',V&Yb
* The beginIndex to set. #UH7z 4u
*/ {1
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publicvoid setBeginIndex(int beginIndex){ d/ OIc){tD
this.beginIndex = beginIndex; ')w*c
} Y">;2Pt;
*ad"3>
/** \$h LhYz-
* @return <P3r}|K
* Returns the currentPage. ~!!>`x
*/ -W+67@(\8H
publicint getCurrentPage(){ w{"GA~=
return currentPage; 1H_#5hd
} p=(;WnsK
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/** 3rZ" T
* @param currentPage (dF4F4`{
* The currentPage to set. VQvl,'z
*/ hexq]' R
publicvoid setCurrentPage(int currentPage){ 8D:{05
this.currentPage = currentPage; 5yQv(<~*G
} , &HZvU&
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/** [@= [<
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* @return r\"O8\
* Returns the everyPage. RfwTqw4@
*/ 9Yowz]')
publicint getEveryPage(){ `8TM<az-L
return everyPage; $E4W{ad2jW
} K,}"v ;||
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/** R6Cm:4m}I
* @param everyPage Tf"DpA!_
* The everyPage to set. >M^
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*/ wDZFOx0#8
publicvoid setEveryPage(int everyPage){ DwZt.*
this.everyPage = everyPage; ys;e2xekg
} @"HR"@pX
@:xO5L}Io
/** d/(=q
* @return zHB{I(q
* Returns the hasNextPage. >{4pEy
*/ zux+ooU
publicboolean getHasNextPage(){ 8y!fqXm%)
return hasNextPage; N)h>Ie
} @X/S
h:
ZjEO$ts=@
/** 5
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* @param hasNextPage B<[;rk
* The hasNextPage to set. E!VAA=
*/ asW1GZO
publicvoid setHasNextPage(boolean hasNextPage){ FV$= l
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this.hasNextPage = hasNextPage; tb0XXEE
} ]+':=&+:
$#@4i4TN-
/**
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* @return ;?2vW8{p<
* Returns the hasPrePage. AEnS_Q
*/ }]zmp/;a
publicboolean getHasPrePage(){ GGF;T&DWad
return hasPrePage; {zUc*9
} "\BP+AF
Whd4-pR8
/** Xx|&%b{{r
* @param hasPrePage ^l^_ K)tw*
* The hasPrePage to set. #s#z@F
*/ G-3.-
publicvoid setHasPrePage(boolean hasPrePage){ #K!Df%,<
this.hasPrePage = hasPrePage; pLzsL>6h
} &,."=G
?GFxJ6!%I
/** OqBw&zm
* @return Returns the totalPage. hDlk! #*
* e^Xij Id.
*/ AD?DIE(v
publicint getTotalPage(){ q 8=u.T
return totalPage; bOck^1Hk y
} kM3BP&
3m1
p!aeL}g`
/** g-p
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* @param totalPage SC2C%.%l`
* The totalPage to set. qqzQKN
*/ t48(GKF
publicvoid setTotalPage(int totalPage){ {C]M]b*F6(
this.totalPage = totalPage; 4rM77Uw>
} I9F[b#'Pn
-'PpY302
} ;@d%<yMf@
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;7`<.y
g=Qga09
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 -Ez|
RaU.yCYyu
个PageUtil,负责对Page对象进行构造: dWqFP
java代码: ^2kWD8c*
iQ9#gPk_9
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/*Created on 2005-4-14*/ <Z m ,q}
package org.flyware.util.page; gv[7h'}<
l(]\[}.5
import org.apache.commons.logging.Log; 5&X
import org.apache.commons.logging.LogFactory; ZHC sv]l
[QZ~~(R
/** z t,-O7I'1
* @author Joa %o"Rcw|
* 9uS7G *
*/ +rT(
publicclass PageUtil { Ox~'w0c,f
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privatestaticfinal Log logger = LogFactory.getLog _).'SU)>
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(PageUtil.class); 'hekCZZ_I
?Nh%!2n
/** =` i 7?
* Use the origin page to create a new page 'o7PIhD"
* @param page Xl/G|jB9
* @param totalRecords /hX"O?^
* @return @&Nvb.5nT
*/ KV5lpN PC
publicstatic Page createPage(Page page, int %C3cdy_c
xapkhIW2\
totalRecords){ ]F@md(J
return createPage(page.getEveryPage(), D+SpSO7yg
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page.getCurrentPage(), totalRecords); \OU+Kl<
} YjX=@
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/** MtYP3:
* the basic page utils not including exception \W}EyA
`5 6QX'?
handler ,#E5 /'c`
* @param everyPage %UQ{'JW?K
* @param currentPage jO,<7FPs5
* @param totalRecords aydal9M
* @return page r6$=|Yto
*/ 0wkLM-lN
publicstatic Page createPage(int everyPage, int eYcx+BJ
I)Lb"
currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); lXPn]iLJ
currentPage = getCurrentPage(currentPage); ya_'Oz!C
int beginIndex = getBeginIndex(everyPage, U2AGH2emw
vLS9V/o
currentPage); kW!:bh
int totalPage = getTotalPage(everyPage, =P#!>*\ar
\a6)t%u
totalRecords); 9/$P_Q:3
boolean hasNextPage = hasNextPage(currentPage, $dnHUBB
Nb#7&_f=
totalPage); WsV3>=@f
boolean hasPrePage = hasPrePage(currentPage); ) ,hj7
>1~`tP
returnnew Page(hasPrePage, hasNextPage, q8h{-^"
everyPage, totalPage, ?8, N4T0)
currentPage, +wUhB\F
*
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beginIndex); 84!4Vz^
} SNU
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privatestaticint getEveryPage(int everyPage){ v 2 GhR*
return everyPage == 0 ? 10 : everyPage; O<h#|g1
} `az`?`i7
cA%U
privatestaticint getCurrentPage(int currentPage){ Zd(d]M_x
return currentPage == 0 ? 1 : currentPage; >slN:dr0:
} (RmED\.]4
:(b3)K
privatestaticint getBeginIndex(int everyPage, int 8e@JvAaa$
7S2F^,w
currentPage){ |+:ZO5FaO
return(currentPage - 1) * everyPage; D%idlL2%J
} >>bYg
_cw^5
privatestaticint getTotalPage(int everyPage, int kV rT?
Mdrv/x{
totalRecords){ M=WE^v!b
int totalPage = 0; #P-HV
X{xJ*T y'
if(totalRecords % everyPage == 0) ~|9LWp_
totalPage = totalRecords / everyPage; sOxdq"E
else .:ZXtU
totalPage = totalRecords / everyPage + 1 ; &iOtw0E
Hm*vKFhz
return totalPage; L||yQH7n
} ZY!pw6R1>*
$cOD6Xr)d
privatestaticboolean hasPrePage(int currentPage){ 1:!rw,Jzl`
return currentPage == 1 ? false : true; R$fIb}PDr
} T+nC>}*jgJ
(bt]GAxb1
privatestaticboolean hasNextPage(int currentPage, ];d:z[\P
W>s'4C`
int totalPage){ C9H11g7{
return currentPage == totalPage || totalPage == 7=.VqC^
pmyM&'#Id
0 ? false : true; c'+r[rSn1
} ;]M67ma7C
'D"K`Vw
R[9PFMn
} fF>qU-
YaZt+WA
|~uzQU7
W:poUG1UR
/e sk
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。 K2rS[Kdfaq
9H}iX0O
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 A4Q)YY9~
K^vp(2
做法如下: z){UuiUM+=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 [a)~Dui0@\
+R#`j r"
的信息,和一个结果集List: ptcLJ]+)
java代码: 8*#][wC2
f76|
CotMV^
/*Created on 2005-6-13*/ Z)O>h^0
package com.adt.bo; Eb[H3v48,
R,w54},
import java.util.List; T :S{3
Zc3:9
import org.flyware.util.page.Page; 5652'p
,q@(L
/** FJ%R3N\
* @author Joa #oroY.o
*/ KO]?>>5S6
publicclass Result { l6B ^sc*@
7k t7^V<
private Page page; =E}%>un
`{|}LFS>
private List content; eN<pU%7
\m~\,em
/** jbhJ;c :
* The default constructor x\bR j>%(
*/ 1xdESorX(
public Result(){ Y5i`pY/}#?
super(); G2+)R^FSC
} Bd oC6H
v*'iWHCl,
/** "p~]m~g
* The constructor using fields S7NnC4)=-f
* BQuliX&
* @param page 8@W/43K8-
* @param content &8_f'+i0
*/ d+m6-4[_k
public Result(Page page, List content){ VVQ74b
this.page = page; (_&V9vat=
this.content = content; (-'0g@0UA
} 1[/$ZYk:
d[RWkk5
/** P$6f +{
* @return Returns the content. ?`
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*/ 9{UP)17
publicList getContent(){ ptWG@"j/b
return content; BtpjQNN
} n#^?X
6KCCbg/
/** &v
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* @return Returns the page. >.O*gv/_
*/ A D}}>v
public Page getPage(){ 22Y!u00D
return page; lGnql 1(
} YKw!pu=
ZLN_,/7
/** 1^60I#Vr@
* @param content W]!@Zlal
* The content to set. 3dX=xuQ%/
*/ (|36!-(iK
public void setContent(List content){ !7kLFW
this.content = content; 17n+4J]
} /_:T\`5uO
}KD7 Y
/** A"BtVy[[9
* @param page A1|7(Sow
* The page to set. KT
lP:pB;
*/ ~D-JZx
publicvoid setPage(Page page){ |>IUtUg\
this.page = page; w$b+R8.n)
} TJyH/C
} h=K36a)
Rg8m4x w
QWzOp\+
C)J_lI{^
clq~ ;hx
2. 编写业务逻辑接口,并实现它(UserManager, ;e~{TkD
#7-kL7 MK]
UserManagerImpl) 1Es*=zg
java代码: k%Ma4_Z
2xL!PR-
e>?_)B4
/*Created on 2005-7-15*/ Q{.{#G
package com.adt.service; "RV`L[(P*k
f!M[awj%
import net.sf.hibernate.HibernateException; |8DH4*y!
Z^'?|qFj!
import org.flyware.util.page.Page; &J lpA<^s;
J8GXI :y
import com.adt.bo.Result; gqP-E
KrdZEi vb
/**
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* @author Joa 9S:{
*/ dN]Zs9]
publicinterface UserManager { inr%XS/m
(C-,ljY
public Result listUser(Page page)throws 4T-,'P{?
KMxNH,5
HibernateException; 2~G,Ia
J{Y6fHFi
} IgPV#
^eTDD
T:K"
#D|!
.I)
Z/89&Uy`h
java代码: lj
"Z
>\|kJ?h
YVQ_tCC_!
/*Created on 2005-7-15*/ la
G$v-r
package com.adt.service.impl; YBYB OH
18DTv6?QG
import java.util.List; M>*0r<qn
E;6Y? vJ
import net.sf.hibernate.HibernateException; ~-XOvKJb
G$?|S@I,
import org.flyware.util.page.Page; 4zo4H~@gk
import org.flyware.util.page.PageUtil; ~q0I7M
N5pinR5 H
import com.adt.bo.Result; Xt</ -`
import com.adt.dao.UserDAO; iGG6Myp-
import com.adt.exception.ObjectNotFoundException; _u:>1]
import com.adt.service.UserManager; Ujce |>Wn
`3f_d}b
/** -Z:]<;qU
* @author Joa U0NOU#
*/ w)45SZ.
publicclass UserManagerImpl implements UserManager { [D*J[?yt
+3M$3w{2
private UserDAO userDAO; eV[`P&j_C
8q]J;T
/** Wmz q
* @param userDAO The userDAO to set. !1ML%}vvB,
*/ cZNi~
publicvoid setUserDAO(UserDAO userDAO){ pwJ'3NbS
this.userDAO = userDAO; ZWf-X
} q*~gWn>T
k_,MoDz
/* (non-Javadoc) 5h_<R!jA
* @see com.adt.service.UserManager#listUser !UBy%DN~k
Sg-g^dIN1
(org.flyware.util.page.Page) N=OS\pz
*/ 8|1`Tn}o
public Result listUser(Page page)throws 5;X {.2
c u\ls^
HibernateException, ObjectNotFoundException { 2{Wo-B,wt~
int totalRecords = userDAO.getUserCount(); ~R :<Bw
if(totalRecords == 0) 7IA3q{P
throw new ObjectNotFoundException V -q%r
:=rA Yc3]
("userNotExist"); FJO"|||Y'|
page = PageUtil.createPage(page, totalRecords); 6exRS]BI
List users = userDAO.getUserByPage(page); DZ^=*.
returnnew Result(page, users); X Y~;)<s_
} %oAL
g(mxhD!k
} zL9VR;q
~}h^38
~_'0]P\
q.-y)C) ;
_e6a8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >R( 8/#|E
`'uUmyg
询,接下来编写UserDAO的代码: }ppVR$7]0
3. UserDAO 和 UserDAOImpl: CV s8s
java代码: *Wzwbwg
h2"9"*S1
-g:lOht
/*Created on 2005-7-15*/ 'nMApPl
package com.adt.dao; A^pu
p?;-!TUv
import java.util.List; zu52 p4
CE{z-_{^
import org.flyware.util.page.Page; D,k(~
5 d+<EF+N
import net.sf.hibernate.HibernateException; 4_tR9 w"
g]za"U|g
/** 0Qm"n6NQ
* @author Joa j8pFgnQ
*/ _WKJ<dB<
publicinterface UserDAO extends BaseDAO { !/947Rn
DMB"Y,
publicList getUserByName(String name)throws xS"$g9o0
.AXdo'&2i
HibernateException; [(1O"
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publicint getUserCount()throws HibernateException; )7W6-.d
;;@IfZ ?j
publicList getUserByPage(Page page)throws l<TIG3bs
K'NcTw#f
HibernateException; )!cI|tovs
W}>=JoN^J
} BjiYv}J
,*dzJT$k
F+Z2U/'a
gA_krK,Z
vVAb'`ysv
java代码: yIOLs}!SF
qbXz7s*{
9mQ#L<Ps
/*Created on 2005-7-15*/ vXb:
package com.adt.dao.impl; $_)=8"Sn
z5 Bi=~=#
import java.util.List; @F?=a*s"!
\83sSw
import org.flyware.util.page.Page;
a"QU:<-v
=O,JAR"ug
import net.sf.hibernate.HibernateException; R*yU<9Mm8
import net.sf.hibernate.Query; MHo1 lrZa+
[h4o7
import com.adt.dao.UserDAO; =D].`
8a9RML}G<
/** =<{ RX8
* @author Joa {rC~P
*/ S8%n .<OB
public class UserDAOImpl extends BaseDAOHibernateImpl JvkL37^n:
^n9a" qz
implements UserDAO { ,-@5NY1q
|z~LzSJv
/* (non-Javadoc) &3Tx@XhO
* @see com.adt.dao.UserDAO#getUserByName x5OC;OQc
noC?k }M
(java.lang.String) ^YKy9zkTl
*/ Ziz=]D_
publicList getUserByName(String name)throws w>qCg XU3
(S oo<.9~
HibernateException { H0a-(
String querySentence = "FROM user in class , H2YpZk
ANMYX18M
com.adt.po.User WHERE user.name=:name"; bD<qNqX$
Query query = getSession().createQuery ,- '4L9
6e .v&f7(
(querySentence); [9V]On
query.setParameter("name", name); F}U5d^!2
return query.list(); #dc1pfL!y{
} )p8I@E
B,_`btJh
/* (non-Javadoc) ''S&e
* @see com.adt.dao.UserDAO#getUserCount() \&a.}t
*/ .
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publicint getUserCount()throws HibernateException { m=TJDr-
int count = 0; g_w&"=.jBq
String querySentence = "SELECT count(*) FROM aI(>]sWJ
K)S;:MLG=
user in class com.adt.po.User"; z856 nl
Query query = getSession().createQuery >|3a
9S
0@)%h&mD
(querySentence); 5j{Np,K
count = ((Integer)query.iterate().next r7 VXeoX
NP/>H9Q2%
()).intValue(); zoP%u,XL
return count; n|i"S`
} :EZQ'3X
++8_fgM
/* (non-Javadoc) by86zX
* @see com.adt.dao.UserDAO#getUserByPage 1$ML #5+,
mJC3@V
s
(org.flyware.util.page.Page) PJgp+u<
*/ 6:?rlh
publicList getUserByPage(Page page)throws )"`!AerJ
4:mCXP,x
HibernateException { kIvvEh<L=
String querySentence = "FROM user in class <\@1Zz@ms
}B q^3?,#{
com.adt.po.User"; 9`"DFFSMS
Query query = getSession().createQuery f:xWu-
dvjTyX
(querySentence); *8)2iv4[
query.setFirstResult(page.getBeginIndex()) F9H~k"_ZJR
.setMaxResults(page.getEveryPage()); (][LQ6Pc
return query.list(); d~*TIN8Ke~
} {8@\Ij
tNnyue{p
} !e3YnlE
Q_zr\RM>
x*}bo))hb
}!)F9r@\
0JY WrPR
至此,一个完整的分页程序完成。前台的只需要调用 [VSU"AJY
EO)%UrWnC
userManager.listUser(page)即可得到一个Page对象和结果集对象 +.Bmkim
iOqk*EL_r\
的综合体,而传入的参数page对象则可以由前台传入,如果用 7Kf}O6nE
(~s|=Hxq|-
webwork,甚至可以直接在配置文件中指定。 LJQJ\bT?
Cca0](R*&
下面给出一个webwork调用示例: 8o-bd_
java代码: 2~c~{ jl\
?Zz'|.l@
[@"wd_f{l
/*Created on 2005-6-17*/ cxP6-tV%
package com.adt.action.user; c
~Fdx
naNyGE7)
import java.util.List; N[U9d}Zv
>dQ K.CG
import org.apache.commons.logging.Log; 8#LJ* o
import org.apache.commons.logging.LogFactory; SH8/0g?
import org.flyware.util.page.Page; ^Jx$t/t
hI|)u4q
import com.adt.bo.Result; $'"8QOnJ?k
import com.adt.service.UserService; ~]uZy=P? 5
import com.opensymphony.xwork.Action; "5!BU&
.g% Y@r)=5
/** Hl7:*]l7b
* @author Joa 0ys~2Y!eH
*/ 1 W'F3
publicclass ListUser implementsAction{ z4M1D9iPY
ftZj}|R!
privatestaticfinal Log logger = LogFactory.getLog @Doyt{|T
=AOWeLk*G
(ListUser.class); Xl%0/o
IFuZ]CBz
private UserService userService; IA*KaX2S<
x?r1s#88>
private Page page; K7`YJp`i
TGV
privateList users; S~F`
7#-y-B]l
/* tRfm+hqRZ
* (non-Javadoc) .FP$ IWt/1
* 5/I_w0
* @see com.opensymphony.xwork.Action#execute() !3}deY8;#
*/ >HTbegi
publicString execute()throwsException{ w+AuMc
Result result = userService.listUser(page); dpzw.Z
page = result.getPage(); ;IZ?19Q
users = result.getContent(); g]$
4~"|.
return SUCCESS; <{ru|-9
}
K5"sj|d&
d"THt}
/** Q9>U1]\
* @return Returns the page. (f1M'w/OD
*/ q<{NO/Mm
public Page getPage(){ O`W%Tr
return page; k%Vv?{g
} g-)mav
cT'w=
/** (ku5WWJ
* @return Returns the users. I6w~H?ul@*
*/ B)=~8wsI:Z
publicList getUsers(){ ($!KzxF3
return users; M##';x0
} e!x6bR9EZ
{aj/HFLNY
/** m],Ud\
* @param page %XRN]tsu
* The page to set. )]Ti>R O7
*/ s#-eN)1R
publicvoid setPage(Page page){ t#~?{i@m
this.page = page; F@vbSFv)/
} 3 <SqoJSp
y]
V1b{9p
/** 'K@0Wp
* @param users _sMs}?^
* The users to set. "Pc$\zJm;
*/ [ygF0-3ND
publicvoid setUsers(List users){ +m$5a
YX
this.users = users; #V_GOy1-
} VWf %v
/iM$Tb5
/** 79Bg]~}Z
* @param userService ?y7w} W
* The userService to set. Of7+/UV
*/ e<\<,)9@/
publicvoid setUserService(UserService userService){ RA1yr+)
this.userService = userService; tIZ~^*'
} :@. ;
} 'jaoO9KY
K
>|udWd^$3
G$JFuz)|
oRY!\ADR
IF_D Z
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, \7 a4uc
J)x3\[}Ye
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 Tj`5L6N;8
;+_8&wbqW
么只需要: JdNF-64ky
java代码: " 'tRfB
UH3t(o7O
_a'A~JY
<?xml version="1.0"?> hU {-a`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;5S}~+j
(H#M<N
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +1`t}hO
9`Q@'(m
1.0.dtd"> IB$7`7
jj&s}_75
<xwork> tJZc/]%`H
d/U."V}
<package name="user" extends="webwork- p+w8$8)
T[uDZYx
interceptors"> O.+9,4A(
$RO$}!
<!-- The default interceptor stack name trYTs,KV
z'MS#6|}
--> ?b:_AO&
<default-interceptor-ref ?9KGnOVu
*e4TSqC|
name="myDefaultWebStack"/> r/r:oXK
S%6U~@hig
<action name="listUser" [_!O<z_sB
E`D%PEps+
class="com.adt.action.user.ListUser"> b`~wGe
<param +!O-kd
p^QZ q>v
name="page.everyPage">10</param> W|UtY`1
<result D<):ZfUbI
shFc[A,r}
name="success">/user/user_list.jsp</result> <d7xt*4
</action> =!0I_L/
1/iE`Si
</package> o$J6 ~dn
3LK%1+)4
</xwork> N6/T#UVns
Fb_S&!
2CLB1
U}AX0*S
WH$HI/%*m
5cTY;@@
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 ^R_e
@.9I3E-=
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 `E>vG-9
Ijo(^v@
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Yp5L+~J[
=3'(A14C=
kX;$}7n
])T/sO#'
SkP[|g'56
我写的一个用于分页的类,用了泛型了,hoho |f' 8p8J
[]p"3i
java代码: X r_pgW|
+_m r
rla:<6tt
package com.intokr.util; XAD3Z?
y-+G
wa3
import java.util.List; @$U e$
vDE |sT
/** Z)9R9s
* 用于分页的类<br> %e=!nRc
* 可以用于传递查询的结果也可以用于传送查询的参数<br> T\sNtdF`:
* t4K56H.L?
* @version 0.01 C0m\SNR
* @author cheng =ApY9`
*/ \ TL82H@D
public class Paginator<E> { k0ItG?Cv
privateint count = 0; // 总记录数 *\ECf.7jz
privateint p = 1; // 页编号 8wFn}lw&
privateint num = 20; // 每页的记录数 P6Xp<^%E
privateList<E> results = null; // 结果 w|Qd`
S+T|a:]\7
/** X"/~4\tJ"
* 结果总数 q=0 pQ1>
*/ %z)EO9vtr
publicint getCount(){ J$[Q?8
ka
return count; nQLs<]h1
} E(Gr0#8
eyB_l.U7
publicvoid setCount(int count){ F(4yS2h(
this.count = count; rsxRk7s@
} z7=fDe
-
uiMIz?+
/** =5s$qb?#
* 本结果所在的页码,从1开始 0dt"ZSm
* J/kH%_ >Ir
* @return Returns the pageNo. dR[o|r
*/ ^k72{ 3N(
publicint getP(){ 'JZ_
return p; QJXdb]Y^;
} 8/q*o>[?
O@,i1ha%
/** YFvgz.>QE
* if(p<=0) p=1 Z_itu73I
* wn84?$BGd
* @param p e,Zv]Cym
*/ v5 Y)al@
publicvoid setP(int p){ 'NjSu64W
if(p <= 0)
rPTfpeqN)
p = 1; 0yQe5i}
this.p = p; g
i4
} (02g#A`
EfSMFPM
/** Oz>io\P94
* 每页记录数量 </ZHa:=7
*/ 9dYOH)f
publicint getNum(){ 3B#!2|
return num; 0/Q5d,'Y[2
} aBlbg3 q
d*9j77C ]
/** [V5-%w^
* if(num<1) num=1 CWMlZVG
*/ /v$]X4 S`
publicvoid setNum(int num){ vKkf2 7
if(num < 1) :?#cDyW)
num = 1; 0O;
Z
this.num = num;
N|N/)
} sT1jF3
"m>};.lj
/** Sf/W9Jw
* 获得总页数 \e0x,2
*/ H%T3Pc
publicint getPageNum(){ 8Mb$+^zU
return(count - 1) / num + 1; u'Pn(A@1R
} 4#@0T"T~M
{~1M
/** i*A$SJ:}
* 获得本页的开始编号,为 (p-1)*num+1 n}5x-SxS0
*/ my=~"bw4
publicint getStart(){ @`2ozi~lO
return(p - 1) * num + 1; .-%oDuB5zF
} v1K4 $&{F
:|fl?{E
/** hhj
,rcsi
* @return Returns the results. :z124Zf
*/ Xr)g
publicList<E> getResults(){ NIL^UN}
return results; U)b&zZc;
} `7$Oh{67
b@F_7P%
public void setResults(List<E> results){ cnYYs d{
this.results = results; M'vXyb%$1
} DW4MA<UQ
yOM
-;h
public String toString(){ h!~|6nj
StringBuilder buff = new StringBuilder "pl[(rc+u
%rX\
P
(); [L)V(o)v
buff.append("{"); Z%A<#%
buff.append("count:").append(count); ":z@c,
buff.append(",p:").append(p); Xe> ~H4I9
buff.append(",nump:").append(num); a1_o.A
buff.append(",results:").append k0=|10bi
N6f%>3%1|.
(results); >sB=\
buff.append("}"); LsUFz_
return buff.toString(); 739l%u }<
} 8Q)y%7{6
l.yJA>\24I
} Hv+:fr"
[lrmuf
!zF4 G,W