Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #sTEQjJ,J
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K*q[(,9
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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 R x7X_A}
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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 .~>?*}
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分页支持类: RBwO+J53y
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java代码: W#'c5:m
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package com.javaeye.common.util; ,E;;wdIt
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import java.util.List; x}TS
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publicclass PaginationSupport { zce`\ /:
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publicfinalstaticint PAGESIZE = 30; {D`'0Z1"
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privateint pageSize = PAGESIZE; S?ujRp
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privateList items; tz^/J=)"
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privateint totalCount; uR;gVO+QC
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privateint[] indexes = newint[0]; )yG"^Ulu
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privateint startIndex = 0; fX~'Zk\u
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public PaginationSupport(List items, int Vw tZLP36
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totalCount){ h6_(?|:-(
setPageSize(PAGESIZE); C NsNZJ
setTotalCount(totalCount); m8R9{LC
setItems(items); R=Zn -q
setStartIndex(0); 7F^#o-@=J
} fu[K".
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public PaginationSupport(List items, int $e1=xSQp4
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totalCount, int startIndex){ O`G/=/GZ
setPageSize(PAGESIZE); t5B7I59
setTotalCount(totalCount); g{IF_ 1
setItems(items); NVKC'==0
setStartIndex(startIndex); e~l#4{w
} = ?D(g
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public PaginationSupport(List items, int sRSz}]
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totalCount, int pageSize, int startIndex){ (8$k4`T>
setPageSize(pageSize); #:jb*d?
setTotalCount(totalCount); b[9&l|y^
setItems(items); {n#k,b&9B
setStartIndex(startIndex); d^03"t0O]
} G!w"{Bk?9
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publicList getItems(){ 5r~#0Zf*
return items; 5 @U<I
} F{06 _T
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publicvoid setItems(List items){ !oPq?lW9
this.items = items; N`iwC!
} PZxAH9 S?
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publicint getPageSize(){ ]i(-I <`
return pageSize; 8Jf.ECQT
} w(ln5q
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publicvoid setPageSize(int pageSize){ De7Ts
this.pageSize = pageSize; -9N@$+T
} S/|,u`g-
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publicint getTotalCount(){ Q!-
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return totalCount; v+p{|X-
} ;g{qYj_
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publicvoid setTotalCount(int totalCount){ 8fA_p}wp
if(totalCount > 0){ mxor1P#|
this.totalCount = totalCount; !It`+0S
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int count = totalCount / )u))n# P
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pageSize; |,9JNm$
if(totalCount % pageSize > 0) #/PA A
count++; afjtn_IB
indexes = newint[count]; !.2<| 24
for(int i = 0; i < count; i++){ ]7-&V-Ct*
indexes = pageSize * u]}s)SmDk
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i; 5F`;yh+e
} RMMd#/A@}
}else{ h(WrL
this.totalCount = 0; R$; n)_H
} /Mb"V5S(W
} OL4z%mDZi
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publicint[] getIndexes(){ +`3!I
return indexes;
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} 9x,RvWTb
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publicvoid setIndexes(int[] indexes){ ss;R8:5
this.indexes = indexes; xsWur(> ]
} 5 ae2<Y=
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publicint getStartIndex(){ [O:
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return startIndex; SG6sw]x
} j*~T1i
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publicvoid setStartIndex(int startIndex){ VfT*7_
if(totalCount <= 0) ~-wPP{!
this.startIndex = 0; j xYc2
elseif(startIndex >= totalCount) v\(2&*
this.startIndex = indexes g{5A4|_7
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[indexes.length - 1]; sz9L8f2
elseif(startIndex < 0) o|jIM9/
this.startIndex = 0; B"%{i-v>**
else{ @?h/B=56
this.startIndex = indexes 6 uKTGc4
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[startIndex / pageSize]; '\jd#Kn'h
} {Zp\^/
} hYawU@R
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publicint getNextIndex(){ \Qm CeB
int nextIndex = getStartIndex() + IIy~[4dW
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pageSize; $s<Ne{?
if(nextIndex >= totalCount) McPNB`.H
return getStartIndex(); y8fsveX
else ;5@ t[r
return nextIndex; xe/(
} {rcnM7 S1L
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publicint getPreviousIndex(){ }NsUnbxT
int previousIndex = getStartIndex() - 4H@Wc^K
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pageSize; c'*a{CV4P
if(previousIndex < 0) T?4G'84nN
return0; 8i?l02
else .7n\d55a
return previousIndex; *Vho?P6y\Y
} y-CX}B#j
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} &w=3^
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抽象业务类 < y*x]}
java代码: dx;k`r$w
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/** OQ9x*TmK
* Created on 2005-7-12 M,ir`"s
*/ C:G8c[
package com.javaeye.common.business; %Q!`NCe+[
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import java.io.Serializable; H{t_xL)k.
import java.util.List; Hk|0HL
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import org.hibernate.Criteria; Vx @|O%
import org.hibernate.HibernateException; <x!GE>sf+
import org.hibernate.Session; UUMtyf
import org.hibernate.criterion.DetachedCriteria; >CkjUZu]&
import org.hibernate.criterion.Projections; J!DF^fLe
import DS<}@
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org.springframework.orm.hibernate3.HibernateCallback; I2H6y"pN
import ~b:Rd{
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org.springframework.orm.hibernate3.support.HibernateDaoS T7f ${
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upport; hS9;k9w
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import com.javaeye.common.util.PaginationSupport; @JRNb=?a
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public abstract class AbstractManager extends ~xoF6CF
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HibernateDaoSupport { q7&6r|w1I
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privateboolean cacheQueries = false; D$JHs4
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privateString queryCacheRegion; #Z5}2soA
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publicvoid setCacheQueries(boolean C{d7J'Avk
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cacheQueries){ Reu*Pe
this.cacheQueries = cacheQueries; owPm/ F
} z.}[m,oTF
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publicvoid setQueryCacheRegion(String ~.!c~fke
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queryCacheRegion){ *&
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this.queryCacheRegion = t3+Py7qv
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queryCacheRegion; \Vl`YYjZ
} Jnv@.
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publicvoid save(finalObject entity){ > ,DbNmi
getHibernateTemplate().save(entity); ;.bm6(;
} WMj}kq)SY)
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publicvoid persist(finalObject entity){ n>'Kp T9|
getHibernateTemplate().save(entity); <G*nDFWf
} ooV*I|wcI
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publicvoid update(finalObject entity){ `g,8-
getHibernateTemplate().update(entity); G-T0f
} ~0b O}
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publicvoid delete(finalObject entity){ $t/x;<.H
getHibernateTemplate().delete(entity); #h@J=Ki
} V"!G2&
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publicObject load(finalClass entity, nF5qw>t#
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finalSerializable id){ kD}Y|*]5-5
return getHibernateTemplate().load P<K){V
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(entity, id); ^#0U ?9
} 7L^%x3-|&
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publicObject get(finalClass entity, sp*Vqd
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finalSerializable id){ ~l2aNVv;
return getHibernateTemplate().get LF0sH)e]
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(entity, id); CwJDmz\tk
} Ks\ NE=;5
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publicList findAll(finalClass entity){ b<]n%Q'n
return getHibernateTemplate().find("from *~/OOH$"
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" + entity.getName()); !'Q -yoHKD
} nQGQWg`
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publicList findByNamedQuery(finalString KeNL0_Pw
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namedQuery){ Dk5Zh+^
return getHibernateTemplate %e@HZ"V
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().findByNamedQuery(namedQuery); A?G^\I~v
} !yhh8p3
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publicList findByNamedQuery(finalString query, A 8 vbQ
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finalObject parameter){ !a~`Bs$'jr
return getHibernateTemplate i%6;
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().findByNamedQuery(query, parameter); kapC%/6"
} z%/N!RLW
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publicList findByNamedQuery(finalString query, *:O.97q@h
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finalObject[] parameters){ 1@gg uRF:
return getHibernateTemplate G7=pBf
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().findByNamedQuery(query, parameters); !p1qJ [
} uw},`4`
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publicList find(finalString query){ R=Tqj,6
return getHibernateTemplate().find 4tx|=;@0
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(query); ?2Kt'1s#
} =tU{7i*+
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publicList find(finalString query, finalObject S"wg2X<
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parameter){ /cZ-tSC)o
return getHibernateTemplate().find cT\I[9!)
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(query, parameter); x2QIPUlf
} phE
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public PaginationSupport findPageByCriteria "6a8s;
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(final DetachedCriteria detachedCriteria){ vLxQ *50v$
return findPageByCriteria r",]Voibd
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Z`&4SH=j
} X w .p
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public PaginationSupport findPageByCriteria L}m8AAkP[
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(final DetachedCriteria detachedCriteria, finalint >{ me
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startIndex){ Zatf9yGD
return findPageByCriteria KFZm`,+69
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(detachedCriteria, PaginationSupport.PAGESIZE, 0qrqg]
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startIndex); 5
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} ip~$X2
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public PaginationSupport findPageByCriteria b~BIz95
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(final DetachedCriteria detachedCriteria, finalint {m`A!qcD|
0 'Vg6E]/
pageSize, s`Cy
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finalint startIndex){ "G:<7oTa
return(PaginationSupport) %{;Qls%[t
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getHibernateTemplate().execute(new HibernateCallback(){ 0[<~?`:)
publicObject doInHibernate 5b/ojr7
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(Session session)throws HibernateException { U=8@@yE
Criteria criteria = i*eAdIi
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detachedCriteria.getExecutableCriteria(session); )fdE6
int totalCount = VGqa)ri"
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((Integer) criteria.setProjection(Projections.rowCount p*5\+WO>!(
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()).uniqueResult()).intValue(); D=TL>T.bf
criteria.setProjection +}Av-47`h
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(null); 1qi@uYDug
List items = *4|Hqa
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criteria.setFirstResult(startIndex).setMaxResults 8q)=
-A-tuyIsh"
(pageSize).list(); ?GBkqQ
PaginationSupport ps = Z2"?&pKV
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new PaginationSupport(items, totalCount, pageSize, US{3pkr;I]
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startIndex); H.G!A6bd
return ps; KLC{7"6e)
} [_xyl e
}, true); dGwszziuK
} ]S 7^ITn
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public List findAllByCriteria(final FEz>[#eOX
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DetachedCriteria detachedCriteria){ ^zEE6i
return(List) getHibernateTemplate 7~M<cD
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().execute(new HibernateCallback(){ $j)hNWI
publicObject doInHibernate 2AVc?
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(Session session)throws HibernateException { F^!mI7Z|(2
Criteria criteria = mKq" 34F
<5@PWrU?[[
detachedCriteria.getExecutableCriteria(session); `P@- %T
return criteria.list(); ]IJv-(
} mDFlz1J,e
}, true); Ri>?KrQF%
} @U -$dw'4
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public int getCountByCriteria(final G%#05jH
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DetachedCriteria detachedCriteria){ a <X0e>
Integer count = (Integer) u&QKwD Uh
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getHibernateTemplate().execute(new HibernateCallback(){ e~v(eK_
publicObject doInHibernate l0tYG[
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(Session session)throws HibernateException { ;1DdjE Tr
Criteria criteria = #~qAHJ<
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detachedCriteria.getExecutableCriteria(session); 3]JZu9#
return zGc(Ef5`M6
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criteria.setProjection(Projections.rowCount AY_Q""v
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()).uniqueResult(); TJ6#P<M
} 59Sw+iZj
}, true); NHX>2-b
return count.intValue(); \Btk;ivg
} [RU
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} oQ+61!5>
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用户在web层构造查询条件detachedCriteria,和可选的 b4,jN~ci
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6-,m}Ce\
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PaginationSupport的实例ps。 &d`^E6#
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ps.getItems()得到已分页好的结果集 N~,_`=yRx
ps.getIndexes()得到分页索引的数组 >Cd9fJ&0gP
ps.getTotalCount()得到总结果数 +C7T]&5s
ps.getStartIndex()当前分页索引 cQpnEO&SL
ps.getNextIndex()下一页索引 kReG:
ps.getPreviousIndex()上一页索引 %Ny) ?B
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -.vDF?@G
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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 qJ[@:&:
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一下代码重构了。 L~FTr
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我把原本我的做法也提供出来供大家讨论吧: 1"K*._K
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首先,为了实现分页查询,我封装了一个Page类: w.kCBDL
java代码: heD,&OX
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/*Created on 2005-4-14*/ :7;[`bm(G
package org.flyware.util.page; +AQDD4bu
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/** >mIg@knE
* @author Joa DacJ,in_I{
* )@:l^$x
*/ ehO:')XF
publicclass Page { zsTbdF
&^ I+s^\=
/** imply if the page has previous page */ 9F_6}.O
privateboolean hasPrePage; ~-Oa8ww
)}X5u%woV
/** imply if the page has next page */ S6 }QFx
privateboolean hasNextPage; = hX[
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/** the number of every page */
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privateint everyPage; P%o44|[][
c"Y!$'|Q
/** the total page number */ h$h]%y
privateint totalPage; sj9D
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/** the number of current page */ x%XT2+
privateint currentPage; ;A^K_w'
|"}4*V_ *
/** the begin index of the records by the current DNth4z
I5pp "*u
query */ t9*=
privateint beginIndex; <lld*IH
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/** The default constructor */ {$TZ}z"DA
public Page(){ aV|k}H{wt
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} |>sv8/!
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/** construct the page by everyPage )W9_qmYd"
* @param everyPage /| GH0L
* */ NV!4(_~
public Page(int everyPage){ Hhf72IX
this.everyPage = everyPage; Wu{&;$
} =WRO\lgv.
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/** The whole constructor */ Dt {')
public Page(boolean hasPrePage, boolean hasNextPage, Y.
TYc;
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e
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int everyPage, int totalPage, :_c*m@=z(
int currentPage, int beginIndex){ 0!IPcZjY7
this.hasPrePage = hasPrePage; |a(Q4 e/,
this.hasNextPage = hasNextPage; ]GS~i+ =M
this.everyPage = everyPage; rUFFF'm\*a
this.totalPage = totalPage; "#XtDpGk
this.currentPage = currentPage; y"R("j $
this.beginIndex = beginIndex; ?cBO6^
} Q eK{MF
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/** 2
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* @return 1#!@["
* Returns the beginIndex. oWrE2U;
*/ 83?1<v0%
publicint getBeginIndex(){ Zi3T~:0p:
return beginIndex; Sf5]=F-w
} Hd*Fc=>"Y
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/** }@*I+\W/
* @param beginIndex foyB{6q8
* The beginIndex to set. {*__B} ,N
*/ 8|vld3;
publicvoid setBeginIndex(int beginIndex){ ruHrv"29
this.beginIndex = beginIndex; .WO/=#O
} qhwoV4@f
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/** %L cH>sV
* @return w@-b
* Returns the currentPage. 0:PSt_33F
*/ w7ZG oh(
publicint getCurrentPage(){ r:#Q9EA
return currentPage; d"!yD/RD
} l qXc
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/** |Pf(J;'[
* @param currentPage D@5s8xv
* The currentPage to set. M4H"].Zm
*/ i?W]*V~ply
publicvoid setCurrentPage(int currentPage){ .S6ji~;r
this.currentPage = currentPage; CjmV+%b4
} 8qmknJC
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/** mLULd} g/o
* @return skK*OO2-
* Returns the everyPage. kyK'
*/ sr4jQo
publicint getEveryPage(){ qhN[Dj(d
return everyPage; .o"<N
} @4&,
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/** ~ ;XYwQ"
* @param everyPage 86#-q7aX
* The everyPage to set. hafECs
*/ tU(y~)]
publicvoid setEveryPage(int everyPage){ 2J&XNV^tJ
this.everyPage = everyPage; C;%Y\S
} ,y%ziay
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/** [tOuNj:
* @return k~R{Y~W!!
* Returns the hasNextPage. P!9;} &
*/ $wgc vySx
publicboolean getHasNextPage(){ E0T&GR@.
return hasNextPage; ?;+ ^
} ,FY-d$3)
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/** 99a\MH`^
* @param hasNextPage DQMPAj.
* The hasNextPage to set. *3P3M}3~\
*/ HIsB|
publicvoid setHasNextPage(boolean hasNextPage){ @kz!{g]Sn
this.hasNextPage = hasNextPage; \w3%[+c
} d4% `e&K]'
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/** ,zD_% ox
* @return **.:)
* Returns the hasPrePage. h)^dB,~
*/ RA}U#D:$i
publicboolean getHasPrePage(){ wLpkUa
return hasPrePage; }$<^wt
} v7L"`
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/** T0YDfo
* @param hasPrePage ^DzL$BX
* The hasPrePage to set. 64h_1,U
*/ ))p$vU3
publicvoid setHasPrePage(boolean hasPrePage){ M5F(<,n;
this.hasPrePage = hasPrePage; gA{'Q\
} ka!Bmv)
-}E)M}W
/** Ri;=aZ5m
* @return Returns the totalPage. l 4!kxXf-<
* [7'#~[a~
*/ @81-kdTx
publicint getTotalPage(){ sRi?]9JIl
return totalPage; _O"L1Let
} C1KfXC*|L
Q
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/** Sf=F cb
* @param totalPage O@nqHZ
* The totalPage to set. QH4k!^
*/ TeKC} NW
publicvoid setTotalPage(int totalPage){ H_Iim[v#
this.totalPage = totalPage; Jc`Rs"2
} \Bt=bu>Z
*}>Bkq9h
} ~:T3|
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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 *wViH
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个PageUtil,负责对Page对象进行构造: ZH_FA
java代码: stX'yya
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/*Created on 2005-4-14*/ sS-W~u|C
package org.flyware.util.page; D!X>O}
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import org.apache.commons.logging.Log; $4DFgvy$
import org.apache.commons.logging.LogFactory; >vHH
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/** 4pLQ"&>}80
* @author Joa f( ]R/'o
* mPckf
*/
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publicclass PageUtil { ;0;3BH A
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privatestaticfinal Log logger = LogFactory.getLog (~=Qufy
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(PageUtil.class); mr@_%U
N )'8o}E
/** I0I_vu
* Use the origin page to create a new page ^OsA+Ea\
* @param page sP9 ^IP
* @param totalRecords 7X(rLd
6#
* @return MhHr*!N"}
*/ 4,j4E@?pG9
publicstatic Page createPage(Page page, int tDEXm^B2Sv
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totalRecords){ =*{K@p_
return createPage(page.getEveryPage(), B"7$!C o
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page.getCurrentPage(), totalRecords); `x2fp6
} qnabw F
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/** $/NGNkl[
* the basic page utils not including exception C]yvK}
o~Bk0V=
handler zA2UFax=
* @param everyPage 01&*`0?
* @param currentPage iSOD&J_
* @param totalRecords UVc>i9,0
* @return page PZKbnu
*/ &6`
publicstatic Page createPage(int everyPage, int PXOrOK
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currentPage, int totalRecords){ 2.^7?ok
everyPage = getEveryPage(everyPage); qJsQb
currentPage = getCurrentPage(currentPage); .Ql;(Wyl
int beginIndex = getBeginIndex(everyPage, %T3j8fC{s
hCU)W1q#
currentPage); &W&7bZ$;
int totalPage = getTotalPage(everyPage, +`Q
PBj^
CHQ{+?#
totalRecords); \7|s$ XQ\
boolean hasNextPage = hasNextPage(currentPage, 7'-)/Pk
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totalPage); 9c"0~7v
boolean hasPrePage = hasPrePage(currentPage); cFRSd
}p=
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returnnew Page(hasPrePage, hasNextPage, <'g0il
everyPage, totalPage, V->.|[J
currentPage, B$K7L'e+-
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beginIndex); nvU+XCx
} Ytl:YzXCi
o@qN#Mg?>}
privatestaticint getEveryPage(int everyPage){ F@>w&A~K
return everyPage == 0 ? 10 : everyPage; =_#ye}E
} &@mvw=d
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privatestaticint getCurrentPage(int currentPage){ {%]NpFg#b
return currentPage == 0 ? 1 : currentPage; {.s ]\C
} $-C6pZN(X
i;E9ZaW
privatestaticint getBeginIndex(int everyPage, int W)6U6
OU0xZ=G
currentPage){ ,\|n=T,
return(currentPage - 1) * everyPage; ]3gYuz|
} ~@b9
==jkp
U*=
privatestaticint getTotalPage(int everyPage, int "U/NMGMj
qg_>`Bv"a
totalRecords){ rg#qSrHp
int totalPage = 0; 8r7/IGFg
|u?k-,uI9
if(totalRecords % everyPage == 0) jK ?
totalPage = totalRecords / everyPage; [+%p!T
else a(Gk~vD;"
totalPage = totalRecords / everyPage + 1 ; ]=$-B
pHI%jHHJ
return totalPage; f)&`mqeE
} r?Ev.m
`~w%Jf
privatestaticboolean hasPrePage(int currentPage){ +^^S'mP8
return currentPage == 1 ? false : true; b&hF')_UOz
} UiGUaB mF*
~G|{qVO7A
privatestaticboolean hasNextPage(int currentPage, >#${.+y
9*GL@_c
int totalPage){ sg! =Q+
return currentPage == totalPage || totalPage == c]cO[T_gGa
J@u!S~&r
0 ? false : true; S>/I?(J
} ,iA2si
73!
x@Duh
B}TInI%H
} =y,yQO
A-AN6.
`4"y#Z
6Dr$*9
U 8qKD
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。 &?`d8\z
;
@[.$Q@I
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 (&N$W&
,b2O^tJF#
做法如下: iTKG,$G
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?kT~)k
Ggxrj'r
的信息,和一个结果集List: &9jUf:g J0
java代码: +e{djp@m
;GSfN
:5q*46n
/*Created on 2005-6-13*/ @; j0c_^"!
package com.adt.bo; zm_hLk
g,z&{pZch
import java.util.List; gZ79u
~gzpX,{n
import org.flyware.util.page.Page; hj#+8=
H)?" 8 s
/** ]0/~6f
* @author Joa +Qb2LR
*/ ]UpHD.Of[t
publicclass Result { c'wU O3S
5. +$v4
private Page page; %_i0go,^
hQW#a]]V:
private List content; $[^ KCNB
=t>`<T|(
/** ZRVF{D??"%
* The default constructor -*]9Ma<wa
*/ [{.\UkV@
public Result(){ SqT"/e]b'
super(); @Tj
6!v
} +wf& L
"_% 0|;
/** X\^3,k."
* The constructor using fields c,u$tnE)
* {F{[!.
* @param page @Ig,_i\UY:
* @param content &55uT;7] a
*/ XTn{1[.O
public Result(Page page, List content){ N;Gf,pE
this.page = page; [/2@=Uh-
this.content = content; 0,i+
} -7A!2mRiz
A`r$fCt1Vi
/** E%v[7 ST
* @return Returns the content. sO f)/19
*/ A$Jn3Xd~!
publicList getContent(){ J4R
return content; 5SPl#*W
} 6I6ZVSxb
}M"'K2_Z
/** b^=8%~?%4
* @return Returns the page. #ui%=ja[:~
*/ `\/Wa h}I
public Page getPage(){ g275{2G9
return page; K+aJ`V
} Q*{ H]
a1Y _0
/** @+Anv~B.
* @param content W3{5Do.h
* The content to set. oR%E_g?mI~
*/ )F9%^a(
public void setContent(List content){ mrBhvp""
this.content = content; [4(A458H
} _ER
cmP
0aq-drl5\
/** `S!uj <-
* @param page %L=h}U13
* The page to set. ysP/@;jC
*/ 0a;FX0S&
publicvoid setPage(Page page){ p44uozbK
this.page = page; c=c.p
i"s
} OKNs (H
} #| e5
K|' ]Hje\
qm&53
}v|[h[cZ
]r{#268
2. 编写业务逻辑接口,并实现它(UserManager, l9Cy30O6
&^Q~G>A
UserManagerImpl) /URj$|
java代码: C
@[9 LB
fJ+E46|4
&cv/q$W4
/*Created on 2005-7-15*/ N7|W.(
package com.adt.service; "i5AAP?_]{
<P)%Ms
import net.sf.hibernate.HibernateException; orN2(:Ct7
FU3IK3}
import org.flyware.util.page.Page; <8}9s9Nk
T)?@E/VaS
import com.adt.bo.Result; WlJRKM2
<zWQ[^
/** Bf}0'MK8zQ
* @author Joa &[\arwe)
*/ '{_tDboY
publicinterface UserManager { AT8,9
peP:5WB
public Result listUser(Page page)throws 5;%xqdD
9<#R;eIsv
HibernateException; PyJblW
FH@e:-*=
} D2mAyU-
sg~/RSJ3
o0v m?CL#
_3?xIT
:zTj"P>"I
java代码: HH7gT
cyn]>1ZM
JSP8Lu"n
/*Created on 2005-7-15*/ >L3p qK
package com.adt.service.impl; S6Xw+W02
S)1:*>@
import java.util.List; @n y{.s+
+hYmL
Sq
import net.sf.hibernate.HibernateException; '3,JL!
-cS4B//IK8
import org.flyware.util.page.Page; 2yg'?tpj
import org.flyware.util.page.PageUtil; A=>6$L];'
t"m`P1
import com.adt.bo.Result; ?q8g<-?
import com.adt.dao.UserDAO; R(#;yn
import com.adt.exception.ObjectNotFoundException; KuAGy*:4T
import com.adt.service.UserManager; /]UNN~(
kUBHK"}K
/** LA(JA
* @author Joa G5@@m-
*/ J~ rC
publicclass UserManagerImpl implements UserManager { W`rE\P
-CNv=vj 3
private UserDAO userDAO; S 2` ;7
V'#u_`x"D)
/** 81 Not
* @param userDAO The userDAO to set. -x5bdC(d
*/ ;:YjgZ:+Q]
publicvoid setUserDAO(UserDAO userDAO){ T{kwy3
this.userDAO = userDAO; %Y[/Ucdm
} )bJ6{&
0md{e`'q:
/* (non-Javadoc) `o- <,
* @see com.adt.service.UserManager#listUser >~r@*gml
ziip*<a!_
(org.flyware.util.page.Page) AZP>\Dq
*/ P =Gb
public Result listUser(Page page)throws zTzG&B-
Q9
",
HibernateException, ObjectNotFoundException { ~|jy$*m4A
int totalRecords = userDAO.getUserCount(); .Zm }
if(totalRecords == 0) aYX '&k
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throw new ObjectNotFoundException ?-p aM5Q+
"K=)J'/n
("userNotExist"); bpCe&*\6K
page = PageUtil.createPage(page, totalRecords); Z@Z`8M@Q,
List users = userDAO.getUserByPage(page); ,S K6*tpI
returnnew Result(page, users); ) FsSXnZL
} $G.|5sEk
U9%nku4
} /R?uxhV
:H k4i%hGk
=?x=CEW
\M^4Dd Ay
M& L0n%,y5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 MH(g<4>*
'\qr=0aW
询,接下来编写UserDAO的代码: FX%E7H
3. UserDAO 和 UserDAOImpl: :jCaDhK
java代码: JG$J,!.\
vIv3rN=5vB
rI$10R$+H
/*Created on 2005-7-15*/ /v<8x?=
package com.adt.dao; 2,`mNjHh
;hp; Rd
import java.util.List; 'KrkCA
cMKh+r
import org.flyware.util.page.Page; }z:=b8}
1EzA@3:{
import net.sf.hibernate.HibernateException; M#,+p8
Unk+@$E&
/** !y0
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* @author Joa b8Sl3F?-~
*/ u>@G:kt8
publicinterface UserDAO extends BaseDAO { %gB0D8,vo
LZ$!=vg4
publicList getUserByName(String name)throws xrd^vE
"aH]4DO
HibernateException; p8bTR!rvz
TR7TF]itb
publicint getUserCount()throws HibernateException; $l0w {m!P
EPfVS
publicList getUserByPage(Page page)throws
X:bgY
yFv3>\
HibernateException; Tl-B[CT
cViCWc2
} ;pYk+r6 Cr
qN(;l&Q
pm|]GkM
3j#F'M)s{
*2hzReM
java代码: Cl=ExpX/O
~Y[b
QuA=)
}x-8@9S~z
/*Created on 2005-7-15*/ L@uKE jR
package com.adt.dao.impl; xEqrs6sR
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import java.util.List; ObnB6ShKi
\`&fr+x
import org.flyware.util.page.Page; A
2 )%+
~d]7 Cl
import net.sf.hibernate.HibernateException; jeNEC&J
import net.sf.hibernate.Query; Dbd5d]]n3
X[}%iEWzT
import com.adt.dao.UserDAO; ponvi42u
n_Dhq (.
/** ;anG
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* @author Joa ,@MPzpH
*/ %hh8\5l.:
public class UserDAOImpl extends BaseDAOHibernateImpl '-qc\6UY
kdq55zTc<6
implements UserDAO { 9wzYDKN}
j/\XeG>
/* (non-Javadoc) =<icHt6s
* @see com.adt.dao.UserDAO#getUserByName N\$6R-L
"a7d`l:
(java.lang.String) :7zI!edu
*/ 64cmv}d _
publicList getUserByName(String name)throws ;2~Q97c0
;DpK*A
HibernateException { x~.U,,1
String querySentence = "FROM user in class Zl*!pQ
1-fz564
com.adt.po.User WHERE user.name=:name"; Zx{'S3W
Query query = getSession().createQuery h
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{I
,'
(querySentence); g*uO
IF
query.setParameter("name", name); 1d6pQ9 N
return query.list(); |ouk;r24V
} Uw!v=n3#!
WF7RMQ51j
/* (non-Javadoc) J0k~%
* @see com.adt.dao.UserDAO#getUserCount() kp|reKM/
*/ 5;*C0m2%i
publicint getUserCount()throws HibernateException { k-/$8C
int count = 0; OZD/t(4?6s
String querySentence = "SELECT count(*) FROM pOXEM1"2A
W*2SlS7
user in class com.adt.po.User"; 9"e!0Q4 0
Query query = getSession().createQuery Y|L57F
JB7]51WH@
(querySentence); &}ow-u9c3
count = ((Integer)query.iterate().next
/uWON4
YL+W4ld
()).intValue(); idq= US
return count; <|@9]>z
} _rv_-n]"o
,&$Y2+
/* (non-Javadoc) /(w5S',EL
* @see com.adt.dao.UserDAO#getUserByPage p#w,+)1!d
"x)W3C%*S
(org.flyware.util.page.Page) $A,=z
*/ U+z&jdnhDR
publicList getUserByPage(Page page)throws Wil+"[Ge
2= _.K(
HibernateException { #"|Ey6&
String querySentence = "FROM user in class cVMTT]cj1
3
V<8
com.adt.po.User"; jB;+tDC!Co
Query query = getSession().createQuery %AFy{l
R?(j#bk
(querySentence); GUxhCoxb
query.setFirstResult(page.getBeginIndex()) !Kis,e
.setMaxResults(page.getEveryPage()); DbDpdC;
return query.list(); /i<g>*82
} [3s~Z8
pP
nz(OHh!}u
} `'/8ifKz
Z-p_hN b
\Z$*8z=
n~h%K7
c
@AwH?7(b
至此,一个完整的分页程序完成。前台的只需要调用 |7 argk+
j'W)Nyw$[
userManager.listUser(page)即可得到一个Page对象和结果集对象 _>*"6
q/Q*1
的综合体,而传入的参数page对象则可以由前台传入,如果用 e:#\Oh
@RjLDj+)S
webwork,甚至可以直接在配置文件中指定。 ? DPL7
O;w';}At
下面给出一个webwork调用示例: c09 uCito
java代码: `7LdF,OdE
C-(&zwj?!
b(yY.L=K
/*Created on 2005-6-17*/ ]T$~a8
package com.adt.action.user; l}m@9 ~oC
#>0nNR[$Y
import java.util.List; }\@*A1*X2
~Oq(JM
$M
import org.apache.commons.logging.Log; '&`Zy pq
import org.apache.commons.logging.LogFactory; K
\O,AE
import org.flyware.util.page.Page; qnOAIP:0
0wx`y$~R
import com.adt.bo.Result; 4x:fOhtP
import com.adt.service.UserService; ?h{ &
import com.opensymphony.xwork.Action; ;RR)C@n1
`
p)#!
/** k,?k37%T]
* @author Joa 'F@'4[uda
*/ milU,!7J
publicclass ListUser implementsAction{ z:w7e0
"Kqe4$
privatestaticfinal Log logger = LogFactory.getLog NTV0DkX
%bAv.'C
(ListUser.class); \t}!Dr+yN
bNXT*HOZb3
private UserService userService; `18G
5R
/h_BF\VBs
private Page page; n@*NQ`(_
[P^ .=F
privateList users; aJub("
xHf
l>C'
/* noacnQ_I$
* (non-Javadoc) YcIk{_N3
* /t816,i
* @see com.opensymphony.xwork.Action#execute() t({:TQ
*/ nF)|oA
publicString execute()throwsException{ \=.iM?T
Result result = userService.listUser(page); "2 Kh2[K
page = result.getPage(); _ZJP]5
users = result.getContent(); s)}C&T$Y.
return SUCCESS; $ED<:[3N
} 3N;X|pa
_ W$4Qn+f
/** "Li"NxObCA
* @return Returns the page. 4YKb~1qkk
*/ YYhRdU/g
public Page getPage(){ GSypdEBj+w
return page; $Q62
7
} Mq$e5&/
BsxQW`>^y
/** f;QWlh"9
* @return Returns the users. P!:D2zSH_
*/ 4re^j4L~o
publicList getUsers(){ 0%v
p'v
return users; &7;W=uF
} w*
v%S
NJ3b Oq
/** (}'0K?
* @param page {4
*ob@w*
* The page to set. B&"fPi
*/ fk=_ Y
publicvoid setPage(Page page){ F$d`Umqs;P
this.page = page; /']Gnt G.
} ?L'ijzP
2nk}'HBe
/** pm^[ve
* @param users NKO5c?ds
* The users to set. h T4fKc7P
*/ A!SHt7ysJ
publicvoid setUsers(List users){ p=T]%k*^h#
this.users = users; [}.OlR3)
} oveW )~4
7GpSWM6
/** 8hdd1lVKO8
* @param userService Wa
, #
* The userService to set. 9[/Gd{`XC
*/ H"m^u6Cmy-
publicvoid setUserService(UserService userService){ B|#"dhT
this.userService = userService; ;l"z4>kt7
} 7u0!Q\
} evq*&.6\
dKhDO`.s
Y!}BmRLh2
{R\ "x|
aabnlOVw
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, bq]af.o*
R:-^,/1
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 0Bb amU
N_h)L`
么只需要: 2UA h^i-^
java代码: flnoK%wi
V9][a
//g~1(
<?xml version="1.0"?> Vc}m_T]O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork CKyX Z
X]M)T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- .pK_j~}P
xrp%b1Sy
1.0.dtd"> Vf,t=$.[Q
~#N^@a
<xwork> MYDAS-
M{1't
<package name="user" extends="webwork- ]=7}Y%6
l\JoWL
interceptors"> )FYz*:f>&
NbSkauF~b
<!-- The default interceptor stack name X^7bOFWE
zq8LQ4@ay
--> [*Wq6n
<default-interceptor-ref [PdatL2
)lE]DG!
name="myDefaultWebStack"/> `#E1FB2M
AKejWh
<action name="listUser" {O[a+r.n
N.l+9L0b
class="com.adt.action.user.ListUser"> 7&qunK'
<param KYZ/b8C
]W]o6uo7
name="page.everyPage">10</param> NN>,dd3T
<result twq!@C
!SMIb(~[z
name="success">/user/user_list.jsp</result> 4,`Yx s)%
</action> vm_+U*%c
S)T~vK(n
</package> )\8l6Gw
/z.Y<xOc
</xwork> 'D;v>r
:dc>\kUIv
#"|</*%>
<}&n}|!
IXDj;~GF
AQw1,tGV
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 (Z fY/
YAYPof~A$l
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。 z1{kZk
xrs?"]M[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 :<r.n
"
IQAV`~_G
;`p+Vs8C
|#^wYZO1U
T@ (MSgp9
我写的一个用于分页的类,用了泛型了,hoho @FKm_q
9nN$%(EO5;
java代码: ^~'tQ}]!"
9w9[0BX#
wM9HZraB<
package com.intokr.util; @GNNi?EY
i7_Nv
import java.util.List; }6*+>?
o$)pJ#";F
/** ]%>7OH'
* 用于分页的类<br> |qnAqzK|
* 可以用于传递查询的结果也可以用于传送查询的参数<br> aAhXHsZ|26
* t6(LO9 Qc
* @version 0.01 [H<![Z1*r
* @author cheng OGpy\0%
*/ 0}tf*M+a
public class Paginator<E> { lI~T>Lel2
privateint count = 0; // 总记录数 ZfsM($|a
privateint p = 1; // 页编号 7}>Zq`]~
privateint num = 20; // 每页的记录数 j}t"M|`
privateList<E> results = null; // 结果 33IJbg
-}#=L@
/** Jh`Pq,B:
* 结果总数 dCc"Qr[k
*/ Fjch<gAofS
publicint getCount(){ &\),V 1"
return count; BPs|qb-
} jGy%O3/
R-QSv$
publicvoid setCount(int count){ Yz7H@Y2i
this.count = count; .,[NJ:l
} +}1h
&\6Buw_
/** gCfAy=-,V
* 本结果所在的页码,从1开始 m.!n|_}]
* mUSrC U_}
* @return Returns the pageNo. 9j<qi\SSI
*/ s2F<H#
publicint getP(){ }.*"ezaZw
return p; Jy<hTd*q
} oHh~!#u
11Sflj
/** m03D+@F
* if(p<=0) p=1 JV_VF'
* bvn%E
H
* @param p ,'!x9 `
*/ Rn?Yz^
1q
publicvoid setP(int p){ 3lr9nBR
if(p <= 0) u*}[fQ`aF
p = 1; tV.qdy/]}
this.p = p; ]rC2jB\,M
} <KY \sb9
@2(7
ZxI
/** [l#
8}dy
* 每页记录数量 n92*:Y
*/ v\lhbpk
publicint getNum(){ Hreu3N
return num; zP554Gr ?
} oW
! Z=;
f
wE
b
/** z3-A2#c
* if(num<1) num=1 j}s<Pn%4
*/ : ;l9to
publicvoid setNum(int num){ ]? 2xS?vd
if(num < 1) M9~eDw'Pr
num = 1; +;#z"m]
this.num = num; B|I9Ex~L
}
Z2P DT
3(o}ulp
/** 7 +]+S`p
* 获得总页数 ~t=73fwB
*/ t .\<Q#bN#
publicint getPageNum(){ Cj/J&PDQ
return(count - 1) / num + 1; ^lvYj
E
} bqPaXH
n
lK VV*RR}
/** G.{)#cR
* 获得本页的开始编号,为 (p-1)*num+1 qe/dWJBa
*/ LOO<)XFJ
publicint getStart(){ {^8->V
return(p - 1) * num + 1; WR|n> i@m
} bv:M
zYS
LI~ofCp
/** 78~;j1^6u
* @return Returns the results. J^w!?nk
*/ s2f6;Yc
publicList<E> getResults(){ reP)&Fo
return results; "5wer5?
t
} dgEH]9j&
Yq~$pVgf
public void setResults(List<E> results){ JX)%iJq#
this.results = results; 3*(w=;y
} pLdZB9oD]C
9M12|X\]8
public String toString(){ }+@GgipyO.
StringBuilder buff = new StringBuilder 2/dvCt6 N
#jqcUno
(); B0+r
buff.append("{"); |YnT;q
buff.append("count:").append(count); C<B+! 16
buff.append(",p:").append(p); PKjM1wqaG@
buff.append(",nump:").append(num); ~fF_]UVq3
buff.append(",results:").append c3__=$)'kP
zk++#rB
(results); Hd_W5R
buff.append("}"); j1~'[
return buff.toString(); 0rrNVaM
} R3bHX%T
H13kNhV9
} ,&F4|{
QKHAN{hJ
1F,>siuh ,