Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uv4jbg}Z+3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ,;;~dfHm
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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 (;0]V+-
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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 4l:+>U@KU
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分页支持类: [;}c@
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java代码: _GS2&|7`
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package com.javaeye.common.util; ;#*mB`
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import java.util.List; Uz6B\-(0p
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publicclass PaginationSupport { u Wtp2]A
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publicfinalstaticint PAGESIZE = 30; u]"RAH
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privateint pageSize = PAGESIZE; uxBk7E%6
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privateList items; V=U %P[S
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privateint totalCount; $J+$8pA
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privateint[] indexes = newint[0]; ?k-IS5G
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privateint startIndex = 0; 3)sqAs(
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public PaginationSupport(List items, int -HOCxR
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totalCount){ 1*5n}cU~
setPageSize(PAGESIZE); fw5AZvE6$
setTotalCount(totalCount); 3!I8J:GZ:
setItems(items); l[gL(p"W
setStartIndex(0); =e63>*M|
} QJ
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public PaginationSupport(List items, int [Z 1Eje X
t{ 'QMX
totalCount, int startIndex){ (NP=5lLH
setPageSize(PAGESIZE); 1FuChd
setTotalCount(totalCount); CBc}N(9
setItems(items); 8w$cj'
setStartIndex(startIndex); d7@ N~<n
} jU=)4nx
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public PaginationSupport(List items, int }k%>%xQ.
}rN"H4)
totalCount, int pageSize, int startIndex){ @Q'5/q+
setPageSize(pageSize); Jv5G:M5+~
setTotalCount(totalCount); E3'6lv'
setItems(items); aw~OvnX E
setStartIndex(startIndex); Z@>>ZS1Do
} U6{ RHS[
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publicList getItems(){ kb>9;-%^JK
return items; *op7:o_
} v / a/
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publicvoid setItems(List items){ R1U\ /
this.items = items; 8<P.>u
} 3B,nHU
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publicint getPageSize(){ HtMlSgx,8>
return pageSize; oY{*X6:6<
} :x_l"y"
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publicvoid setPageSize(int pageSize){ WTXTr0=
this.pageSize = pageSize; y
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} d;f,vN(
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publicint getTotalCount(){ Bk8U\Ut
return totalCount; *H;&hq
} >$}nKPC,Y
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publicvoid setTotalCount(int totalCount){ d(k`Yk8
if(totalCount > 0){ ;$Wa=wHb
this.totalCount = totalCount; y};qo'dlt
int count = totalCount / 9,,1\0-T*
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pageSize; 'oo]oeJ-
if(totalCount % pageSize > 0) Cu>pql<O
count++; k(Ow.nkb
indexes = newint[count];
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for(int i = 0; i < count; i++){ y`'Ly@s
indexes = pageSize * L%fWa2P'
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} fY>\VY$>
}else{ !\p-|51
this.totalCount = 0; Um%E/0j
} |%$d/<<PZ
} l*h6JgU
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publicint[] getIndexes(){ ]t<%v_K
return indexes; /+'@}u
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} -5.>9+W8I
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publicvoid setIndexes(int[] indexes){ B^eea [
this.indexes = indexes; +1e*>jE
} g-6!+>w*>e
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publicint getStartIndex(){ ?
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return startIndex; Oyz=|[^,W
} dNIY`u
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publicvoid setStartIndex(int startIndex){ fz<Y9h=
if(totalCount <= 0) >5 Ce/P'R
this.startIndex = 0; Oi7|R7NE
elseif(startIndex >= totalCount) <{e0i
this.startIndex = indexes %R(j|a9z
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[indexes.length - 1]; |i1z47jN6P
elseif(startIndex < 0) UUX
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this.startIndex = 0; hd+JKh!u
else{ i^j{l_-JE
this.startIndex = indexes W&GDE
594$X@!v
[startIndex / pageSize]; \,~gA
} 0\u_\%[
} eQzTb91
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publicint getNextIndex(){ #[J..i/h
int nextIndex = getStartIndex() + 6Ba>l$/q
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pageSize; ;u, 5
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if(nextIndex >= totalCount) n1$p
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return getStartIndex(); 2_U H, n
else 5JQq?e)n
return nextIndex; cpf8f i
} ~ 5`Ngpp
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publicint getPreviousIndex(){ }k'8*v}8
int previousIndex = getStartIndex() - r)ga{Nn,.
sd
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pageSize; ?zxKk(J
if(previousIndex < 0) 8>
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return0; M1VRc[
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else s|dL.@0,L
return previousIndex; AQ@A$
} VM|8HR7U
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} PLwa!j
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抽象业务类 :x= ZvAvo
java代码: r0?`t!%V
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/** <#sB ;
* Created on 2005-7-12 CfA
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*/ S =eP/
package com.javaeye.common.business; *9*6n\~aI
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import java.io.Serializable; <Eq^rh
import java.util.List; (Z
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import org.hibernate.Criteria; 7-bU9{5
import org.hibernate.HibernateException; 7J##IH+z35
import org.hibernate.Session; Oxy.V+R
import org.hibernate.criterion.DetachedCriteria; "!r7t4
import org.hibernate.criterion.Projections; O]i}r`E8,
import %5jxq9:K
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org.springframework.orm.hibernate3.HibernateCallback; IN),Lu0K
import ,NKDEcw]
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org.springframework.orm.hibernate3.support.HibernateDaoS amgYr$)m
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upport; QfRt3\^`
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import com.javaeye.common.util.PaginationSupport; v:<u0B-)$
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public abstract class AbstractManager extends (~,Q-w"
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HibernateDaoSupport { 7RTp+FC]
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privateboolean cacheQueries = false; (8k3z`
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privateString queryCacheRegion; ytr~} M%
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publicvoid setCacheQueries(boolean 7teg*M{
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cacheQueries){ ]`]m41+w
this.cacheQueries = cacheQueries; yAXw?z!`O
} <c^m|v
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publicvoid setQueryCacheRegion(String |Ax~zk;
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queryCacheRegion){ ?ZE1>L7e
this.queryCacheRegion = 8x[q[
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queryCacheRegion; "P'W@
} cMIQbBM
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publicvoid save(finalObject entity){ VI[ikNpX
getHibernateTemplate().save(entity); 1/JgirVA
} -.i1l/FzP
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publicvoid persist(finalObject entity){ _D[vMr[
getHibernateTemplate().save(entity); {BDp`uZ
} #2{ };)
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publicvoid update(finalObject entity){ "~N#Jqzr:
getHibernateTemplate().update(entity); ci6j"nKci
} [gQ*y~N
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publicvoid delete(finalObject entity){ 5}E8Tl
getHibernateTemplate().delete(entity); HmAA?J}
} pX*Oc6.0mu
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publicObject load(finalClass entity, ~g~z"!K
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finalSerializable id){ d* 7 Tjs{\
return getHibernateTemplate().load C/tn0
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(entity, id); \<]nv}1O
} hA/K>Z
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publicObject get(finalClass entity, _Z@- q
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finalSerializable id){ C$-IDBXK
return getHibernateTemplate().get 1j9 .Q;9
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(entity, id); Ik(TII_
} 5! NK
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publicList findAll(finalClass entity){ t/#[At5p=
return getHibernateTemplate().find("from =uIu0_v
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" + entity.getName()); 39BGwKXb
} ccZ A
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publicList findByNamedQuery(finalString G<Z|NT
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namedQuery){ hF.9\X]
return getHibernateTemplate Yhb=^)@))
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().findByNamedQuery(namedQuery); "fL:scq@0
} Lg
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publicList findByNamedQuery(finalString query, *U)!9DvA
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finalObject parameter){ Yq $(Ex
return getHibernateTemplate vLXN{ ]
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().findByNamedQuery(query, parameter); tz6d}$
} x3MV"hm2
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publicList findByNamedQuery(finalString query, gV91=Pj
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finalObject[] parameters){ bN8GRK )
return getHibernateTemplate kViX FPW
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().findByNamedQuery(query, parameters); Q!(C$&f
} ,9`sC8w|
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publicList find(finalString query){ w<lHY=z E
return getHibernateTemplate().find 3BDAvdJ4.
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(query); EdhT;!
} )ZEUD] X
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publicList find(finalString query, finalObject 7xb z)FI
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parameter){ QyuSle
return getHibernateTemplate().find O\,n;oj
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(query, parameter); l23_K7
} S ])Ap'E
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public PaginationSupport findPageByCriteria cP''
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(final DetachedCriteria detachedCriteria){ c8v+eyn
return findPageByCriteria IX7<
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); HcXyU/>D
} lUJ/ nG0l
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public PaginationSupport findPageByCriteria wyzj[PDS
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(final DetachedCriteria detachedCriteria, finalint #(mm6dj
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startIndex){ T@;z o8:
return findPageByCriteria TyY[8J|
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(detachedCriteria, PaginationSupport.PAGESIZE, Dt0S"`^=k
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startIndex); Uvgv<OR`_
} 5P9hm[
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public PaginationSupport findPageByCriteria yQ?N*'}$
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(final DetachedCriteria detachedCriteria, finalint s?@{
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pageSize, K'+GK S7.
finalint startIndex){ *Em 9R
return(PaginationSupport) [ Lt1OdGl
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getHibernateTemplate().execute(new HibernateCallback(){ T^x7w+
publicObject doInHibernate UQgOtqL3
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(Session session)throws HibernateException { S 0eD
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Criteria criteria = ]&`_5pS
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detachedCriteria.getExecutableCriteria(session); US A!N
int totalCount = |kyxa2F{
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((Integer) criteria.setProjection(Projections.rowCount ?vuM'UH-
:?2+'+%'
()).uniqueResult()).intValue(); n8DWA`[ib
criteria.setProjection 9JV(}v5[
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(null); ^} P|L
List items = OM*N) *
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criteria.setFirstResult(startIndex).setMaxResults _Il/ i&
.9_]8T
(pageSize).list(); 3/+9#
PaginationSupport ps = QkBT,c
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new PaginationSupport(items, totalCount, pageSize, PdcF
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startIndex); n|dLK.Q
return ps; W|_
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} H)(@A W+-
}, true); !:PF |dZ
} FVNxjMm,
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public List findAllByCriteria(final S/Pffal
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DetachedCriteria detachedCriteria){ vi')-1Y
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return(List) getHibernateTemplate OiH
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().execute(new HibernateCallback(){ 6*u#^">,<
publicObject doInHibernate ^UHt1[
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(Session session)throws HibernateException { 'L4@|c~x
Criteria criteria = 9`yG[OA
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detachedCriteria.getExecutableCriteria(session); t$^1A1Ef
return criteria.list(); Z[<rz6%cB
} ,rVm81-2
}, true); i$gm/ZO
} r\Nf309~
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public int getCountByCriteria(final O3WhO@`6)
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DetachedCriteria detachedCriteria){ :SUPGaUJ"
Integer count = (Integer) 0Po",\^
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getHibernateTemplate().execute(new HibernateCallback(){ _\waA^ F
publicObject doInHibernate -Zc
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(Session session)throws HibernateException { p!BZTwP
Criteria criteria = 7t= e"|^
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detachedCriteria.getExecutableCriteria(session); ~9c?g(0
return DP **pf%j
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criteria.setProjection(Projections.rowCount _Bm/v^(
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()).uniqueResult(); :=WiT_M
} RO"c+|Py
}, true); @ de_|*c
return count.intValue(); $BKGPGmh
} }UNRe]ft$
} F* "
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用户在web层构造查询条件detachedCriteria,和可选的 ~&B{"d
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 HEH Tj,T
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PaginationSupport的实例ps。 M7!>-P
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ps.getItems()得到已分页好的结果集 -02cI}e
ps.getIndexes()得到分页索引的数组 gp'9Pf;\[
ps.getTotalCount()得到总结果数 T^.;yU_B?
ps.getStartIndex()当前分页索引 Lsa&A+fru
ps.getNextIndex()下一页索引 +InAK>NZ'
ps.getPreviousIndex()上一页索引 x
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 SRs1t6&y=
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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 by; %k/
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一下代码重构了。 U,
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我把原本我的做法也提供出来供大家讨论吧: ^]:w5\DG
LdxrS5
首先,为了实现分页查询,我封装了一个Page类: `F5iZWW1
java代码: .U|irDO
nI4Kuz`dF
R!IODXP=
/*Created on 2005-4-14*/ IGz92&y
package org.flyware.util.page; ;v%Fw!b032
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/** |hms'n0
* @author Joa Ks
8
* G?D7R/0)
*/ l",JN.w
publicclass Page { *6D0>F
_aa3;kT_
/** imply if the page has previous page */ J60XUxf
privateboolean hasPrePage; 5u
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'q%56WAJ
/** imply if the page has next page */ pleLdGq
privateboolean hasNextPage; xL8r'gV@
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/** the number of every page */ mYLqT$t.+
privateint everyPage; l_bvwo
h8@8Qw
/** the total page number */ 2Zt :]be
privateint totalPage; e~]3/ 0
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/** the number of current page */ y)iT-$bQ
privateint currentPage; $D{KXkrd
*Kj*| >)
/** the begin index of the records by the current .^6;_s>FN
a+A^njk
query */ +oa\'.~?
privateint beginIndex; ,#&\1Vxf
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/** The default constructor */ f P'qUN
public Page(){ 7u[U %yd
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} umPd+5i
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/** construct the page by everyPage 48;6C g
* @param everyPage ct,B0(]
* */ m(MPVY<X
public Page(int everyPage){ ?sfas57&y
this.everyPage = everyPage; `o~dQb/k+
} iSDE6
| R MIV
/** The whole constructor */ K.3)m]dCl
public Page(boolean hasPrePage, boolean hasNextPage, %:i; eUKR
2fZVBj
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int everyPage, int totalPage, XaT9`L<
int currentPage, int beginIndex){ )~/;Xl#b-
this.hasPrePage = hasPrePage; 0>@D{_}s
this.hasNextPage = hasNextPage; N-XOPwx'
this.everyPage = everyPage; /5cFa
this.totalPage = totalPage; 6mcxp+lm|
this.currentPage = currentPage; _}MO.&Y
this.beginIndex = beginIndex; =eG?O7z&
} DmDsn
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/** ^s*j<fH
* @return anDwv
}
* Returns the beginIndex. i-1lpp I
*/ mZGAl1`8
publicint getBeginIndex(){ 5G5P#<Vv
return beginIndex; zTA+s 2
} &'%b1CbE
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/** dkTewT6'
* @param beginIndex M"cB6{st[
* The beginIndex to set. #4hxbRN
*/ tA#7Xr+
publicvoid setBeginIndex(int beginIndex){ 5f5bhBZ<
this.beginIndex = beginIndex; ,/{(8hn
} /S4$qr cM
j1/.3\
/** u,h ,;'J
* @return Ns?qLSN
* Returns the currentPage. L~x
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*/ pkWJb!
publicint getCurrentPage(){ l!r2[T]I@7
return currentPage; `re9-HM
} 7G,{BBB
1Z9_sd~/6
/** b.=bgRV2{x
* @param currentPage Fh2$,$
2
* The currentPage to set. xd[GJ;xvs
*/ fP|rD[
publicvoid setCurrentPage(int currentPage){ gz{~\0y
this.currentPage = currentPage; |Z\?nZ~
} o}EipTL
>%qk2h>
/** "9mVBa|Q
* @return DeqTr:
* Returns the everyPage. 8sMDe'
*/ +7yirp~`K
publicint getEveryPage(){ &)(>e}es
return everyPage; 2|="!c8K
} 9 Vn
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/** Vz=ByyC
* @param everyPage AH*{Bi[vX
* The everyPage to set. l,z#
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*/ +|Tz<\.C
publicvoid setEveryPage(int everyPage){ F.9SyB$
this.everyPage = everyPage; /-Saz29f^Q
} FE}!I
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/** 9VqE:c /
* @return NO(^P+s
* Returns the hasNextPage. %BdQ.\4DS
*/ f?KHp|
publicboolean getHasNextPage(){ p]/qf\E
return hasNextPage; U`{'-L.
} "Jd!TLt\x
rL{3O4O
/** >Yr-aDV
* @param hasNextPage @UbH;m
* The hasNextPage to set. z ^e99dz
*/ +ZuT\P&kR5
publicvoid setHasNextPage(boolean hasNextPage){ I+qg'mo
this.hasNextPage = hasNextPage; qG=?+em
} 977%9z<h
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/** 96L-bBtyY
* @return JnC$}amr
* Returns the hasPrePage. /O,>s
*/ (#|CL/ &
publicboolean getHasPrePage(){ f9+J}
return hasPrePage; G~$.Af!9W
} ejr9e@D^
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/** J%8M+!`F
* @param hasPrePage 0F"W~OQ6
* The hasPrePage to set. ~&zrDj~FI
*/ MCPVql`+`q
publicvoid setHasPrePage(boolean hasPrePage){ }]dK26pX
this.hasPrePage = hasPrePage; &E{CQ#k
} 8$!&D&v
Qqp_(5S|>
/** 4*j6~
* @return Returns the totalPage. &m=GkK
* dA)JR"r2
*/ o'oA.'ul
publicint getTotalPage(){ (8Q0?SZN
return totalPage; )K=%s%3h<
} 3K8#,TK3
5y
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/** @W4tnM,#
* @param totalPage .G ^-.p
* The totalPage to set. #hp7@ Tu
*/ {}sF?wZf
publicvoid setTotalPage(int totalPage){ gD13(G98
this.totalPage = totalPage; uX.^zg]}%
} e8WuAI86
+ESEAi91
} iy<|<*s2D
nC:>1kt
aw%iO|M_
UR3qzPm!0e
qocN:Of1
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 E{Kc$,y
L|?$F*bs
个PageUtil,负责对Page对象进行构造: _H,xnh#nZ
java代码: >MTrq%.
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/*Created on 2005-4-14*/ 3"*tP+H
package org.flyware.util.page; fbTq?4&Q
)S:,q3gxJ
import org.apache.commons.logging.Log; 1g{-DIOmn
import org.apache.commons.logging.LogFactory; Nld y76|g
u<g0oEs)
/** Q)/V>QW
* @author Joa b7^Db6qu
* $dxk;V
*/ |41NRGgY
publicclass PageUtil { $wr B5m?
KQf=t0Z=Ce
privatestaticfinal Log logger = LogFactory.getLog m{ wk0
6-fdfU
(PageUtil.class); pmWt7 }
+jEtu[ ;
/** 9}[UZN6
* Use the origin page to create a new page Q.U
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* @param page '3p7ee&
* @param totalRecords Jbv[Ql#
* @return R&-Vm3mc3
*/ &x":
publicstatic Page createPage(Page page, int ?Z0NHy;5
(&B`vgmb
totalRecords){ vcmB)P-T`O
return createPage(page.getEveryPage(), /wR,P
iBM;$0Y
page.getCurrentPage(), totalRecords); wHT]&fZ
} xg;o<y KF
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/** #VvU8"u
* the basic page utils not including exception } SNZl`>
xg^Z. q)d
handler O)aWTI
* @param everyPage rA\6y6dFs
* @param currentPage Z!& u_
* @param totalRecords /<R[X>]<F
* @return page mA?fCs
*/ 8|"26UwD/
publicstatic Page createPage(int everyPage, int iwXMe(k
tl=H9w&@
currentPage, int totalRecords){ 1_jd1UT
everyPage = getEveryPage(everyPage); NimW=X;c
currentPage = getCurrentPage(currentPage); G<$N*3
int beginIndex = getBeginIndex(everyPage, ;4'pucq5/
'!DS3zEeLS
currentPage); tP.jJC~
int totalPage = getTotalPage(everyPage, H{BP7!t[V
]aMeMhe-
totalRecords); m-HL7&iG$
boolean hasNextPage = hasNextPage(currentPage, m ]h<y
6IPQ}/l
totalPage); (a9>gLI0
boolean hasPrePage = hasPrePage(currentPage); 4lF(..Ix
rqi/nW
returnnew Page(hasPrePage, hasNextPage, FK+`K<
everyPage, totalPage, s=H|^v
currentPage, 8#{DBWU
_C%:AFPP>
beginIndex); E]0}&YG
} 9 WO|g[Y3
ls@j8bVv^
privatestaticint getEveryPage(int everyPage){ PB(q9gf"1}
return everyPage == 0 ? 10 : everyPage; c gOkm}h
} \Q!I;
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privatestaticint getCurrentPage(int currentPage){ RYyM;<9F
return currentPage == 0 ? 1 : currentPage; p.|M:C\xL
} q2e=(]rKE{
9 S4bg7
privatestaticint getBeginIndex(int everyPage, int $X_A74(
KCl85Wi'
currentPage){ KNG7$icG
return(currentPage - 1) * everyPage; NVX @1}
} 'JRYf;9c
>X_5o^s2s
privatestaticint getTotalPage(int everyPage, int =#>F' A
\|YIuzlO4
totalRecords){ :V!F~
int totalPage = 0; p9-s' F|@i
rQsYt/
if(totalRecords % everyPage == 0) eUVhNg
totalPage = totalRecords / everyPage; 63fgl+
else UGP,/[XI
totalPage = totalRecords / everyPage + 1 ; aCF=Og
g2%fla7r
return totalPage; KL\hV .6
} #oD; ?Mi
$4:Se#nl
privatestaticboolean hasPrePage(int currentPage){ He)!Ez\X
return currentPage == 1 ? false : true; _Q9I
W
} z=6zc-$y 9
D$U`u[qjtS
privatestaticboolean hasNextPage(int currentPage, mlO\wn-F
&e\UlM22
int totalPage){ X]4j&QB
return currentPage == totalPage || totalPage == ]S 3l' "
IKVFbTX:y
0 ? false : true; O^~Z-;FA
} E*"oA1/I
>/+R~ n
yA]OX" T?*
} 1d 1
~`B
4ATIF;G'<
(H6Mi.uZ
A4daIhP
(
ECk*
H
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #Dp]S,e
K"jS,a?s 6
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 P$zhMnAAN
hf\/2Vl
做法如下: uE,g|51H/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 tF:AqR:(~
w_P2\B^
的信息,和一个结果集List: R.KznJ
java代码: 6E{(_i
O?t49=uB}
9/JBn
/*Created on 2005-6-13*/ V~sfR^FQ'
package com.adt.bo; ]@uuB\u
* /^}
import java.util.List; mRIBE9K+&
;;K
~
import org.flyware.util.page.Page; 4+J>/ xiZ
qH(HcsgD
/** dC>(UDC
* @author Joa @xeJ$
rlu
*/ tz9"#=}0
publicclass Result { tu' s]3RE
abw5Gz@Ag
private Page page; 6w4HJZF~
)lU9\"?o
private List content; @^.o8+Pp
DN;|?oNZ
/** ]Q#k"Je
* The default constructor E?FUr?-[
*/ *)L~1;7j>
public Result(){ gu"@*,hL
super(); yRR[M@Y
} 9v/=o`J#
'fYF1gR4
/** #$;}-*
* The constructor using fields ^/I.? :+
* b(\Mi_J
* @param page \ #N))gAQ
* @param content ^p~QHS/
*/ i`5Skr:M
public Result(Page page, List content){ &Qmb?{S0
this.page = page; $IqubC>O
this.content = content; :{9HsF"h0
} ]P e8G(E!
)jjL'
/** yN/g;bQ
* @return Returns the content. ]wwN mmE
*/ Vqr]Ui
publicList getContent(){ ar_@"+tZ
return content; jLn|zK
} !JtM`x/yR
YjiMUi\V
/** _
glB<r$
* @return Returns the page. =>XjChM
*/ yO`
|X
public Page getPage(){ HWFLu
return page; s Fx0
} 9)>+r6t
ECk3Da
/** ]xGpN ]u
* @param content eo~b]D
* The content to set. /!%?I#K{Wq
*/ tn;{r
public void setContent(List content){ /VD[: sU7
this.content = content; 2BiFP||
} (+SL1O P
:j? MEeu
/** 6xFchdMG{m
* @param page Dutc#?bT
* The page to set. I|wC`VgB
*/ B`YD>oCN
publicvoid setPage(Page page){ CwD=nT5`
this.page = page; Vjd(Z
} s4j]kH
} {Ve3EYYm
Vha,rIi
UW1i%u
k
51-'*Y
}0sLeGJ!
2. 编写业务逻辑接口,并实现它(UserManager, xd\ml
37~
L)qUBp@MW
UserManagerImpl) }a;H2&bu
java代码: CF:L#r
jO9!:L>b`
nNeCi
/*Created on 2005-7-15*/ ,~/WYw<o
package com.adt.service; _
^'QHWP
ilyF1=bp
import net.sf.hibernate.HibernateException; ?_r{G7|D
[930=rF*
import org.flyware.util.page.Page; wYLodMaYH
l[u17,]S
import com.adt.bo.Result; 8@b`a]lgrd
putRc??o;
/** ui-]%~
* @author Joa ^CgN>-xZ?#
*/ MS:,I?
publicinterface UserManager { Dp4x\97O
uzT+,
public Result listUser(Page page)throws /N#=Tol
hAt4+O&P
HibernateException; ;GKL[tI"
oF a,IA
} 1M b[S{
ObJ-XNcNH
<oi'yr
s>W :vV@
* U}-Y*
java代码: #U4
f9.FY*
N3zZ>#{
t/_\w"
/*Created on 2005-7-15*/ =[zP
package com.adt.service.impl; ^nK 7&]rK
DWEDL[{
import java.util.List; e1y#p3 @d
(BngwLVDK
import net.sf.hibernate.HibernateException; )CHXfO w
jT/P+2hMW
import org.flyware.util.page.Page; p2< 927z
import org.flyware.util.page.PageUtil; 4>HaKJ-c#
JLz32 %-M
import com.adt.bo.Result; U ^nv)
import com.adt.dao.UserDAO; n^b CrvD
import com.adt.exception.ObjectNotFoundException; \RtFF
import com.adt.service.UserManager; V(:wYk?ZR
22;B:
/** y^[t3XA6Q
* @author Joa o5sw]R5
*/ uF1&m5^W
publicclass UserManagerImpl implements UserManager { ^vTx%F
Ya>AI.!K
private UserDAO userDAO; [qxU
\OSC
Vf.*!`UH
/** \B:k|Pw6~
* @param userDAO The userDAO to set. O jNOvh&N
*/ ~d3@x\I?
publicvoid setUserDAO(UserDAO userDAO){ eo@8?>}{X
this.userDAO = userDAO; >ts}\.(]
} .5AFAGv_c
d`C$vj
/* (non-Javadoc)
NFP h}D
* @see com.adt.service.UserManager#listUser R*D5n>~
*]}F=dtR k
(org.flyware.util.page.Page) `'*4B_.
*/ :_]0 8
public Result listUser(Page page)throws
?6>*mdpl
4q:8<*W=
HibernateException, ObjectNotFoundException { J}+N\V~
int totalRecords = userDAO.getUserCount(); G9V2(P
if(totalRecords == 0) ?3qp?ea
throw new ObjectNotFoundException >56fa6=3@
UbGnU_}
("userNotExist"); "5z@A/Z/
page = PageUtil.createPage(page, totalRecords); )v*k\:Hw
List users = userDAO.getUserByPage(page); KeB??1S
returnnew Result(page, users); [La}h2gz
} D?8(n=#[
OCJt5#e~A
} Q`NdsS2
:WsHP\r
/Oi(5?Jn
Z{:;LC
RZKx!X4=q
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 'n1$Y%t
.{ZJywE<
询,接下来编写UserDAO的代码: J7C?Z
3. UserDAO 和 UserDAOImpl: HG< z,gE
2
java代码: -T i<H9OV
xWqV~NnE
k Jw
Pd;%
/*Created on 2005-7-15*/ M X?UmQ'
package com.adt.dao; AAW] Y#UwW
lrwQ
>N
import java.util.List; ]~VuY:abH
-QR]BD%J*[
import org.flyware.util.page.Page; Qx3eEt@X5]
]=ZPSLuEm%
import net.sf.hibernate.HibernateException; 'h7x@[|
if*~cPnN
/** aMxj{*v7
* @author Joa ~l?c.CSd
*/ N$v_z>6Z
publicinterface UserDAO extends BaseDAO { _L` uCjA
u^B! 6Sj8
publicList getUserByName(String name)throws :-<30LS$
nqx0#_K-E
HibernateException; 63_#*6Pv28
Ayv:Pv@
publicint getUserCount()throws HibernateException; 5''k|B>
cH$(*k9%M
publicList getUserByPage(Page page)throws dtTfV.y4w
7cWeB5e?O
HibernateException; [i.c;'Wy/
W`c$2KS?DO
} 6rWq
hIaI
R,["w98a
\ltS~EuWU
xLLTp7b(
{T,}]oX
java代码: US^%pd
$T:;KcW)
[` }w7
/*Created on 2005-7-15*/ PFx.uqp
package com.adt.dao.impl; f Ayh9
iOCs%J
import java.util.List; `QRXQ c
auX(d -m
import org.flyware.util.page.Page; bA2[=6
PhV/WjCZ
import net.sf.hibernate.HibernateException; X8}\m%gCU
import net.sf.hibernate.Query; YlT&.G
2TQZu3$c
import com.adt.dao.UserDAO; %X^qWKix}m
4p+Veo6B
/** i%F2^R@!q/
* @author Joa Csp$_uDi
*/ 1zG6^U
public class UserDAOImpl extends BaseDAOHibernateImpl ?(Tin80=r
=./PY10'
implements UserDAO { y`5
?
JUj.:n2e
/* (non-Javadoc) (CH6Q]Wi_!
* @see com.adt.dao.UserDAO#getUserByName K>LS8,8V
.iP>?9$f"
(java.lang.String) @Q{:m)\
*/
)*6
publicList getUserByName(String name)throws #H4<8B
a5O$he
HibernateException { 0H.bRk/P+
String querySentence = "FROM user in class f%1\1_^g
7fzH(H
com.adt.po.User WHERE user.name=:name"; M
#0v# {o
Query query = getSession().createQuery K^[m--
~;pP@DA
(querySentence); ahZ@4v
query.setParameter("name", name); lKU{jWA
return query.list(); `#85r{c$:
} C+ Y;D:
n9 FA`e
/* (non-Javadoc) 7\$ b%A
* @see com.adt.dao.UserDAO#getUserCount() c yP+a
*/ -|s%5p|
publicint getUserCount()throws HibernateException { {~R?f$}""j
int count = 0; _D@QsQ_Z
String querySentence = "SELECT count(*) FROM } _];yw
f\=,_AQ
user in class com.adt.po.User"; ZAeJTCCk
Query query = getSession().createQuery ]9'F<T= $_
v0(}"0
(querySentence); 3D5adI<aq"
count = ((Integer)query.iterate().next ",[ /pb
g`C"t3~%S
()).intValue(); 2XV|(
return count; @MFEBc}
} nGK=Nf.5
$7xfLS8Vo
/* (non-Javadoc) uh#E^~5S
* @see com.adt.dao.UserDAO#getUserByPage jjv'"K2
F3$8l[O_
(org.flyware.util.page.Page) BILZ XMf
*/ Mh3L(z]/E
publicList getUserByPage(Page page)throws |HJ`uGN<b
)k[XO
HibernateException { _Gb7n5p
String querySentence = "FROM user in class ,1!Y!,xy
Wnp[8IEU
com.adt.po.User"; X|g5tnsj`
Query query = getSession().createQuery 1cMdoQ
hBcklI
(querySentence);
E5|GP
query.setFirstResult(page.getBeginIndex()) t1oTZ
.setMaxResults(page.getEveryPage()); y,KZp2 j
return query.list(); n>:e8KVM;
} qPUACuF'
:
4lR`%
} cFJZ|Ld
rW~G'
,If"4C!w
'Cz]p~oF
eYjF"Aq
至此,一个完整的分页程序完成。前台的只需要调用 "]'W^Fg
_U*1D*kLI[
userManager.listUser(page)即可得到一个Page对象和结果集对象 6 !fq658
$Op:-aW&
的综合体,而传入的参数page对象则可以由前台传入,如果用 8Jp?@qt=$
prIJjy-F
webwork,甚至可以直接在配置文件中指定。 Oq3t-omXS
!^1oH**
下面给出一个webwork调用示例: B%))HLo'
java代码: (U.VCSn
nHfAx/9!
=M4wP3V/
/*Created on 2005-6-17*/ K&dc< 4DC
package com.adt.action.user; u8<Fk
!
uV'C_H
import java.util.List; ,g|ht%"
eUgKwu;
import org.apache.commons.logging.Log; %\B?X;(
import org.apache.commons.logging.LogFactory; 6/(Z*L"~6k
import org.flyware.util.page.Page; (f#{<^ gd
)^)|b5,
import com.adt.bo.Result; ;D4
bxz0ou
import com.adt.service.UserService; Kl(u~/=6
import com.opensymphony.xwork.Action; ~aL?{kb+
Hb^ovc0
/** lfwBUb
* @author Joa v"J|Ebx
*/ cj[%.M5iBA
publicclass ListUser implementsAction{ H66~!J0;a
oK"#*n
privatestaticfinal Log logger = LogFactory.getLog Av/y
[f$pq5f='
(ListUser.class); [E}pU8.t6
Nk F2'Z{$+
private UserService userService; RcI0n"Gi_
=)Goip
private Page page; ::/vDUDc
y>g`R^^
privateList users; x^pHP|<3`
SQuW`EHBgs
/* t +CU
* (non-Javadoc) IueI7A
* Ye>+
* @see com.opensymphony.xwork.Action#execute()
)$2h:dw_
*/ g%4=T~
publicString execute()throwsException{ lgHzI(
Result result = userService.listUser(page); .
vea[
page = result.getPage(); -#AO4xpI
users = result.getContent(); eN<?rVZl
return SUCCESS; Mt121Q&"
} oT}Sh4Wt.
cavzXz
/** G)9`Qn
* @return Returns the page. T=pKen/
*/ 2&F H8
public Page getPage(){ AAc2u^spx
return page; +2s][^-KV
} z}7U>y6`
cn_ *,\}
/** DJR r
* @return Returns the users. \&Oc}]
*/ ]#$rTWMl'
publicList getUsers(){ 0Jm)2@
return users; k@2@%02o9C
} ]5eZLXM
yfe4}0}
/** 0:>C v<N
* @param page Yb>A?@S
* The page to set. bLz('mUY
*/ v,c:cKj
publicvoid setPage(Page page){ `%0k\,}V
this.page = page; 8uetv
} ,aSK L1
>vQKCc|93
/** lMXLd91
* @param users QPsvc6ds
* The users to set. k=5v
J72U
*/ t$U eks
publicvoid setUsers(List users){ +r__>V,
this.users = users; Be0v&Q_NK
} |DoD.?v
,#80`&\%
/** _,|N`BBqd
* @param userService Pill |4 c<
* The userService to set. 6
Zv~c(
*/ LGC3"z\=
publicvoid setUserService(UserService userService){ AjO|@6
this.userService = userService; ot,e?lF
} Jb`yK@x
} At8^yF
6b=7{nLF
>zcp(M98
,6^V)F
e&XJK*Wf
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, ~2U5Wt
)%(H'omvl
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 TZ@S?r>^
&0@AM_b
么只需要: ?rububDT{
java代码: nA XWbavY
@?<1~/sfL
7.1FRxS
<?xml version="1.0"?> ~C ;gEE-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork EcmyY,w
1cPjgBxv#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- qu0dWgK
=doOt 7Rj
1.0.dtd"> j2,w1f}T
NpxND0
<xwork> ~-2q3U Py
-D,kL
<package name="user" extends="webwork- JAcNjzL
9TOqA4
interceptors"> i@spd5.
Gw}b8N6E
<!-- The default interceptor stack name Yu9.0A_) :
"Bbd[ZI8
--> H=7Nh6v
<default-interceptor-ref RB/;qdqR
2o9IP>#u
name="myDefaultWebStack"/> HpTX6}^
FPXB>D'
<action name="listUser" yM*<BV
$iAd)2LT
class="com.adt.action.user.ListUser"> _^u^@.Q'i<
<param I r;Z+}4>Y
_8nT$!\\
name="page.everyPage">10</param> +h?z7ZY^
<result _f~m&="T!
e.pq6D5
name="success">/user/user_list.jsp</result> i?pC[Ao-_
</action> #_[W*-|L
RiM!LX
</package> g7U>G=,;?U
a$P$Ngi?S
</xwork> |+(Hia,X
]k.'~Syz
QDJ:LJz\
w`r)B`!g
#`{L_n$c
j+>&~
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 ?;)F_aHp
.</.(7
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。 w?zY9Fs=s
b&Go'C{p
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Y]Y]"y$1
9$:+5f,%a
#^&.*'z%z
e.ksN
8ORr
我写的一个用于分页的类,用了泛型了,hoho 5Dlx]_
aXO|%qX
java代码: r:uW(<EP^
Di8;Tq
\mp5G&+/Q
package com.intokr.util; [xsiSt?6
iKN800^u
import java.util.List; 4 Z<
/C)FS?=
/** X mX
.)h'Y
* 用于分页的类<br> $y&1.caMa
* 可以用于传递查询的结果也可以用于传送查询的参数<br> [E/}-m6g
* qQ "O;_
* @version 0.01 AilfeHG
* @author cheng $*i"rlJC
*/ _ 0Ced&i
public class Paginator<E> { bB|P`lL
privateint count = 0; // 总记录数 "sU ~|
privateint p = 1; // 页编号 -6u#:pVpU
privateint num = 20; // 每页的记录数 qo" _w%{
privateList<E> results = null; // 结果 z("Fy
0al8%z9e@
/** GcYT<pwN6
* 结果总数 :Y ;\1J<b1
*/ LQrm/)4bF5
publicint getCount(){ Ghpk0ia%d
return count; ,HM~Zs
} [r5k8TB1
Jz6,2,LN
publicvoid setCount(int count){ '}q1 F<&
this.count = count; %/x%hs;d
} znl_~:.4]X
Tx'ctd#Y
/** N$SJK
* 本结果所在的页码,从1开始 +B0G[k7
* ^ M4-O~
* @return Returns the pageNo. K'zG[[P
*/ {l -V
publicint getP(){ v
lsS
return p; 8^Ov.$rP
} !p~K;p,
H;OPA8\n
/** f:-dw6a=s
* if(p<=0) p=1 Ew kZzVuX
* t846:Z%[
* @param p W=k%aB?p
*/ Ly$s0.!
publicvoid setP(int p){ z.7'yJIP#
if(p <= 0) )bGd++2
p = 1; )4P5i
b
this.p = p; TGJ\f
} wzRIvm{
?~5J!|r#
/** Xqac$%[3
* 每页记录数量 S(f V ,;Z
*/ 8?7gyp!k_f
publicint getNum(){ :>t?^r(
return num; GCgpe(cQ
} G$D6#/rR
4U*uH
/** H}$hk
* if(num<1) num=1 An%V>a-[
*/ ;|Ja|@82
publicvoid setNum(int num){ zjrr*iw
if(num < 1) mxRe2<W
num = 1; S-Y(Vn4
this.num = num; `(9B(&t^,
} /B?hM&@z
6/#5TdJA
/** mJ%r2$/*
* 获得总页数 Y%V|M0 0`
*/ d">Ya !W
publicint getPageNum(){ 9$xEktfV
return(count - 1) / num + 1; plY`lqm
} *0^t;A+
'*KP{"3\
/** !I? J^0T
* 获得本页的开始编号,为 (p-1)*num+1 FDAREE\j
*/ Qp?n0WXZ
publicint getStart(){ ^gdg0y!5~
return(p - 1) * num + 1; -e{H 8ro
} pw7_j;}l
!\NKu1ta
/** M]>JI'8
* @return Returns the results. N
-]m <z>
*/ }<wj~f([
publicList<E> getResults(){ pP'-}%
return results; 3o'SY@'W
} YJ5;a\QxN
~%Ws"1
public void setResults(List<E> results){ uxto:6),P<
this.results = results; 3\,TI`^C
} Xm`K@hJ@
JHf}LZu
public String toString(){ C%P"Ds=w0N
StringBuilder buff = new StringBuilder hfvs'.
e;=G|E
(); b* 6c.
buff.append("{"); NRKAEf_#w
buff.append("count:").append(count); uREc9z`Q'
buff.append(",p:").append(p); ~P5!VNJ;r
buff.append(",nump:").append(num); Ej1 [ry
buff.append(",results:").append Dz&4za+{
b)u9#%Q
(results); d]e`t"Aj
buff.append("}"); <C4^Vem
return buff.toString(); X/1Z9a+W
} <EI'N0~KG
w9}I*Nra
} Y54*mn
v]*W*;
uF T\a=