Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 109dB$+$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fT.18{'>
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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 ^0py
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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 0Am&:kX't
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分页支持类: wO9|_.Z{
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java代码: FOVghq@
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package com.javaeye.common.util; ~o_0RB
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import java.util.List; /5 yjON{
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publicclass PaginationSupport { 0=O(+
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publicfinalstaticint PAGESIZE = 30; +A%|.;
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privateint pageSize = PAGESIZE; 15dhr]8E
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privateList items; Ey96XJV
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privateint totalCount; 2*;qr|h,
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privateint[] indexes = newint[0]; qg1s]c~0u
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privateint startIndex = 0; 3'tcEFkH
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public PaginationSupport(List items, int -!i1xR(;h
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totalCount){ Pt< JF
setPageSize(PAGESIZE); PJ}d-
setTotalCount(totalCount); 8p D$/
setItems(items); w3l2u1u
setStartIndex(0); m#6RJbEz
} *g7BR`Bt]z
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public PaginationSupport(List items, int 4P(muOS
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6
totalCount, int startIndex){ 'kU5
setPageSize(PAGESIZE); w]L^)_'Th
setTotalCount(totalCount); 3{c6)vR2
setItems(items); J]G]
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setStartIndex(startIndex); ;IyA"C(i
} En!X}Owh
}@6Tcn1
public PaginationSupport(List items, int D!7-(3R
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totalCount, int pageSize, int startIndex){ s1
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setPageSize(pageSize); ((0nJJjz
setTotalCount(totalCount); 0b=1Ce+0q
setItems(items); 3Ye{a<ckK
setStartIndex(startIndex); _EPfeh;
} ;::]R'F[
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publicList getItems(){ zm>^!j
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return items; Y oDL/
} g{ ()
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publicvoid setItems(List items){ EKu%I~eM
this.items = items; [G!#y
} hp|.hN(kS]
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publicint getPageSize(){ qAI%6d
return pageSize; T'6MAxEZUq
} zTBf.A;e7
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publicvoid setPageSize(int pageSize){ &|9K~#LVS
this.pageSize = pageSize; a
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} KBC?SxJSJc
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publicint getTotalCount(){ ?Vre"6U
return totalCount; [D%(Y
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} ^(F@ #zN}
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publicvoid setTotalCount(int totalCount){ s5s'[<
if(totalCount > 0){ -v %n@8p
this.totalCount = totalCount; px${
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int count = totalCount / %eOO8^N
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pageSize; l+nT$IPF
if(totalCount % pageSize > 0) wn-1fz<d
count++; *Jwx,wF}4
indexes = newint[count]; ldFR%v>9
for(int i = 0; i < count; i++){ zgNzdO/B
indexes = pageSize * J7;8
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i; /7N&4FrG
} }3O 0nab
}else{ ;kDUQw
this.totalCount = 0; \>$3'i=mQ
} rP{Jep!
} P,J+'.@
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publicint[] getIndexes(){ xovsh\s
return indexes; MxgJ+
} zq(4@S-TU
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publicvoid setIndexes(int[] indexes){ Z% DJ{!Hnh
this.indexes = indexes; @{>0v"@
} pC~M5(F_
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publicint getStartIndex(){ :X}n[K
return startIndex; 9Iu"DOxX%
} .H@b zm
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publicvoid setStartIndex(int startIndex){ ~^TH5n
if(totalCount <= 0) R53^3"q~
this.startIndex = 0; Xp+lpVcJ
elseif(startIndex >= totalCount) r;^%D(
this.startIndex = indexes j7BLMTF3v
VUi> ]v/e
[indexes.length - 1]; )+Y"4?z~
elseif(startIndex < 0) =PF2p'.o
this.startIndex = 0; D7r&z?
else{ s0O]vDTR,H
this.startIndex = indexes [ $5u:*
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[startIndex / pageSize]; n$ rgJ
} Xub*i^(]
} b:5-0uxjs
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publicint getNextIndex(){ n)0M1o#
int nextIndex = getStartIndex() + '%X29B5
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pageSize; #w3J+U 6r
if(nextIndex >= totalCount) < 1%}8t"
return getStartIndex(); !r8_'K5R(
else bvOnS0,y
return nextIndex; k!ID
} oJZxRm[g$t
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publicint getPreviousIndex(){ RFLfvD<
int previousIndex = getStartIndex() - IH&0>a
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pageSize; _NB*+HVo
if(previousIndex < 0) "F =NDF
return0; -{}h6r
else y/E:6w
return previousIndex; 7},oY""8
} i)$P1h
?7]G)8G6
} Fge["p?GF
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抽象业务类 ,k_"T.w
java代码: q_6fr$-Qh
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/** ?nPG#Z|%
* Created on 2005-7-12 h
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*/ U9\\8
package com.javaeye.common.business; ohbU~R3{U
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import java.io.Serializable; -u(,*9]cJ*
import java.util.List; Lk!m1J5
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import org.hibernate.Criteria; 6J\ 2=c`
import org.hibernate.HibernateException; }L(ZLt8Q
import org.hibernate.Session; Y0Tad?iC
import org.hibernate.criterion.DetachedCriteria; suzK)rJ9i
import org.hibernate.criterion.Projections; kia[d984w
import rFGPS%STS
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org.springframework.orm.hibernate3.HibernateCallback; L2p?]:-
import 064k;|>D
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org.springframework.orm.hibernate3.support.HibernateDaoS $E&T6=Wn
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upport; c~4Cpy^
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import com.javaeye.common.util.PaginationSupport; &l0K~7)b
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public abstract class AbstractManager extends /@|iI<|
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HibernateDaoSupport { }AA">FF'y4
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privateboolean cacheQueries = false; X4]miUmh
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privateString queryCacheRegion; m 94PFD@N
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publicvoid setCacheQueries(boolean %g:'6%26
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cacheQueries){ 1)^\R(l
this.cacheQueries = cacheQueries; =.7tS'
} EcL6lNTR+
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publicvoid setQueryCacheRegion(String 4b[bj").A
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queryCacheRegion){ h]h"-3
this.queryCacheRegion = g5y`XFY
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queryCacheRegion; ;py9,Wno
} @!=Ds'MJC
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publicvoid save(finalObject entity){ {f\wIZ-K A
getHibernateTemplate().save(entity); L{P'mG=4
} aPzn4}~/_
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publicvoid persist(finalObject entity){ JH{/0x#+
getHibernateTemplate().save(entity); "5L?RkFi\
} >t.Lc.
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publicvoid update(finalObject entity){ 4~3
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getHibernateTemplate().update(entity); *~g*J^R}
} F{;#\Ob
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publicvoid delete(finalObject entity){ ~CT]&({
getHibernateTemplate().delete(entity); n<bU' n
} AwXzI;F^
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publicObject load(finalClass entity, z?<B@\~
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finalSerializable id){ 5\# F5s}
return getHibernateTemplate().load %SOXw8-
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(entity, id); >zqaV@T
} 4/|x^Ky>G
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publicObject get(finalClass entity, {daX?N|V
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finalSerializable id){ r) x
return getHibernateTemplate().get W,NqevXo:
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(entity, id); >U,&V%y
} jhm/<=
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publicList findAll(finalClass entity){ 3!b
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return getHibernateTemplate().find("from $/s"It
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" + entity.getName()); s[{[pIH
} nf^?X`g
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publicList findByNamedQuery(finalString /^AH/,p
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namedQuery){ ]CF-#q}'
return getHibernateTemplate ppRmC,0f^
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().findByNamedQuery(namedQuery); 4WvW11q8U
} @>Yd6C
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publicList findByNamedQuery(finalString query, .*x:
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finalObject parameter){ mFF4qbe
return getHibernateTemplate >2znn&gZ
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().findByNamedQuery(query, parameter); ~jL%l
} Q__CW5&'u
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publicList findByNamedQuery(finalString query, p/-du^:2
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finalObject[] parameters){ x6`mv8~9Db
return getHibernateTemplate HP.=6bJWi
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().findByNamedQuery(query, parameters); It[51NMal
} c'i5,\ #X
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publicList find(finalString query){ 7S}0Kuk)
return getHibernateTemplate().find VkFh(Br<{
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(query); E xhih^[_
} ?YW~7zG
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publicList find(finalString query, finalObject bFX{|&tHU
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parameter){ qR'FbI
return getHibernateTemplate().find /eQAGFG
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(query, parameter); LZn'+{\`
} aDdGhB
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public PaginationSupport findPageByCriteria W_2;j)i
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(final DetachedCriteria detachedCriteria){ nZbI}kcm
return findPageByCriteria
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{!|4JquE_
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3[[oAp
} 8X,6U_>#a
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public PaginationSupport findPageByCriteria [Kwj
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(final DetachedCriteria detachedCriteria, finalint Vx $;wU Y
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startIndex){ 'Tm1Mh0Fso
return findPageByCriteria ,GH`tK_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0 #8
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startIndex); DEZww9T2Qs
} {nV/_o$$
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public PaginationSupport findPageByCriteria lAU99(GXV
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(final DetachedCriteria detachedCriteria, finalint L~6%Fi&n4
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pageSize, XYo,5-
finalint startIndex){ !kE5]<H\
return(PaginationSupport) 5!F;|*vC8
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getHibernateTemplate().execute(new HibernateCallback(){ N]+6<
publicObject doInHibernate Q~(Gll;
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(Session session)throws HibernateException { UTkPA2x
Criteria criteria = Q~U\f$N
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detachedCriteria.getExecutableCriteria(session); UGPDwgq\v
int totalCount = Vu5?;|^:
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((Integer) criteria.setProjection(Projections.rowCount P1mg;!tq
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()).uniqueResult()).intValue(); q}P@}TE
criteria.setProjection %l7[eZ{Y
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(null); z;qDl%AF
List items = StI
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criteria.setFirstResult(startIndex).setMaxResults ^#:;6^Su
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(pageSize).list(); IA` voO$
PaginationSupport ps = 8TP$ ?8l
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new PaginationSupport(items, totalCount, pageSize, vXDs/,`r
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startIndex); x0<;Rm [u=
return ps; .#yg=t1C
} EsGu#lD2
}, true); lMY\8eobcB
} '3>;8(sl
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public List findAllByCriteria(final Ljy797{f
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DetachedCriteria detachedCriteria){ [9">}l
return(List) getHibernateTemplate LIID(s!bX
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().execute(new HibernateCallback(){ yvB]rz} i
publicObject doInHibernate yzS^8,
@Go_5X(
(Session session)throws HibernateException { juHL$SGC
Criteria criteria = T)mQ+&|
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detachedCriteria.getExecutableCriteria(session); <[db)r~c
return criteria.list(); vywB{%p
} ZexC3LD"
}, true); cI2Ps3~"Q
} H a!,9{T
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public int getCountByCriteria(final jR/Gd01)
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DetachedCriteria detachedCriteria){ wp?:@XM
Integer count = (Integer) kd'b_D[$H
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getHibernateTemplate().execute(new HibernateCallback(){ s%D%c;.|
publicObject doInHibernate # ?2*I2_
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(Session session)throws HibernateException { (e7!p=D
Criteria criteria = d {!P
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, /.@([C
detachedCriteria.getExecutableCriteria(session); Q#p)?:o/
return *wTX
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criteria.setProjection(Projections.rowCount !K-1tp$
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()).uniqueResult(); <j'K7We/tP
} rbd0`J9fq
}, true); Dd?G4xUG
return count.intValue(); agUdI_'~@9
} ^)dsi
} CPJ<A,V
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用户在web层构造查询条件detachedCriteria,和可选的 G+c&e:ip<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ^OV; P[
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PaginationSupport的实例ps。 `
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ps.getItems()得到已分页好的结果集 zb0NqIN:
ps.getIndexes()得到分页索引的数组 u2#q7}
ps.getTotalCount()得到总结果数 ud/!@WG
ps.getStartIndex()当前分页索引 v<1@"9EH
ps.getNextIndex()下一页索引 84(Jo_9
ps.getPreviousIndex()上一页索引 (@^9oN~}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0fqcPi
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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 e i=
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一下代码重构了。 (pELd(*Ga
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我把原本我的做法也提供出来供大家讨论吧: uc,>VzdB
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首先,为了实现分页查询,我封装了一个Page类: Mq91HmC(@
java代码: gN/!w:
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/*Created on 2005-4-14*/ )?72 +X
package org.flyware.util.page; eCI'<^
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/** 0/QDfA?
* @author Joa g]f<k2
* 29:2Xu i
*/ sPK ]:iC
publicclass Page { 1sXCu|\q
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/** imply if the page has previous page */ "W5MZ
privateboolean hasPrePage; hE:~~ox
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/** imply if the page has next page */ 9':Ipf&x
privateboolean hasNextPage; G!FdTvx$
n~lB}
/** the number of every page */ _h1bVd-
privateint everyPage; Sj ovL@X
@JSWqi>
/** the total page number */ ( %7V
privateint totalPage; ?h `,@~6u
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/** the number of current page */ 0s`6d;
privateint currentPage; o*$KiD
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/** the begin index of the records by the current 1XN%&VR>^D
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query */ fS}Eu4Xe
privateint beginIndex; ](oeMl18R
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/** The default constructor */ 7O)ATb#up
public Page(){ }6l:'nW
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} G:e=9qTf
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/** construct the page by everyPage 3JD62wtx
* @param everyPage ;*5z&1O
* */ Dml?.-Uv<
public Page(int everyPage){ 9?Bh8%$
this.everyPage = everyPage; hEjvtfM9\-
} "0!#De
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/** The whole constructor */ D?ic~-&
public Page(boolean hasPrePage, boolean hasNextPage, z\v
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int everyPage, int totalPage, @IL@|Srs8
int currentPage, int beginIndex){ y6am(ugE
this.hasPrePage = hasPrePage; Q8HNST($?
this.hasNextPage = hasNextPage; 0^{Tq0Ri[
this.everyPage = everyPage; YEV;GFI1
this.totalPage = totalPage; 86%k2~L
this.currentPage = currentPage; q!&:y7O8
this.beginIndex = beginIndex; N_D=j6B
} }*XF- U
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/** jYU0zGpj
* @return FBNi (D
* Returns the beginIndex. ]oix))'n
*/ i8<5|du&?
publicint getBeginIndex(){ oi Q3E
return beginIndex; i.9}bw
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} ';eAaDM
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/** 5@.8O VPz
* @param beginIndex KUW )F
* The beginIndex to set. <> =(BAw
*/ 9on$0
publicvoid setBeginIndex(int beginIndex){ }!g$k
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this.beginIndex = beginIndex; CEk[&39"
} GF9iK|i/
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/** "=?JIQ
* @return e>Q:j_?.e
* Returns the currentPage. PJb/tKC
*/ f:q2JgX
publicint getCurrentPage(){ 937<:zo:
return currentPage; QdZHIgh`i
} AJ
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/** d}E6d||A
* @param currentPage ;d7Qw~v1s
* The currentPage to set. L%7WHtU*#
*/ R
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publicvoid setCurrentPage(int currentPage){ ,DKW_F|
this.currentPage = currentPage; ]$K5 8C
} -b%' K}.C
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/** }2y"F@{T
* @return mznE Cy
* Returns the everyPage. q+YK NXI
*/ >taT
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publicint getEveryPage(){ R{4[.
return everyPage; wj$3L3
} g[2[
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/** gO~>*q &
* @param everyPage '@^<c#h]=
* The everyPage to set. aLevml2:T
*/ j~2t^Qz
publicvoid setEveryPage(int everyPage){ -J!k|GK#MX
this.everyPage = everyPage; Iq;a!Lya-
} #$t93EI
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/** .@(MNq{"6
* @return Ky7-6$
* Returns the hasNextPage. ^oHK.x#{
*/ U,/9fzgd
publicboolean getHasNextPage(){ ;hDIoSz
return hasNextPage; $>~4RXC
} mpCKF=KL.
mnMY)-6C
/** 6l?KX
* @param hasNextPage >*w(YB]/$V
* The hasNextPage to set. d cht8nX7~
*/ 5PHAd4=bJ
publicvoid setHasNextPage(boolean hasNextPage){ Wm58[;%LTw
this.hasNextPage = hasNextPage; ,J-YfL^x6*
} cRPy5['E
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/** `Oi6o[a
* @return n@e|PWu
* Returns the hasPrePage. $/i;UUd
*/ doe u`
publicboolean getHasPrePage(){ fl9J
return hasPrePage; N'5!4JUI
} M\9p-%"L
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/** [ \i1I`7pE
* @param hasPrePage Q5v_^O<!
* The hasPrePage to set. bF3}L=z
*/ NE$=R"<Gv
publicvoid setHasPrePage(boolean hasPrePage){ .!Q[kn0a
this.hasPrePage = hasPrePage; \h/aD1&g
} l< |)LDq~
v/Ei0}e6~
/** !U+XIr
* @return Returns the totalPage. {,m W7
* l3/?,xn
*/ wvSaq+N
publicint getTotalPage(){ 0/%VejZ'
return totalPage; UD r@
} Jqi^Z*PuX
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/** ^$O,Gy) V
* @param totalPage HQ8;d9cGir
* The totalPage to set. n47v5.Wn
*/ b{d@:"
publicvoid setTotalPage(int totalPage){ t?kbN\,
this.totalPage = totalPage; C@
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} \xaK?_hv
g*#.yC1/
} gTP0:
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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 $'VFb=?XrK
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个PageUtil,负责对Page对象进行构造: <[GkhPfZ
java代码: tm}0kWx
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/*Created on 2005-4-14*/ fL&bN[XA"$
package org.flyware.util.page; ) crhF9 !4
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import org.apache.commons.logging.Log; '`Z5.<n7p
import org.apache.commons.logging.LogFactory; {o[*S%Z"
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/** `=3:*.T*
* @author Joa i/UHDqZ
* i~6qOlLD-
*/ oos7x6
publicclass PageUtil { DrB PC@^
FCEFg)c5=
privatestaticfinal Log logger = LogFactory.getLog V"@]PI pr
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(PageUtil.class); vN%SN>=L<
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/** #Hr>KQ5mJQ
* Use the origin page to create a new page ZK@ENfG
* @param page H?>R#Ds-
* @param totalRecords !7-dqw%l
* @return w+~s}ta2^
*/ %A dE5HI-
publicstatic Page createPage(Page page, int R"=pAO.4l
xeX Pc7JG
totalRecords){ >{^&;$G+*
return createPage(page.getEveryPage(), W`^Zb[
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page.getCurrentPage(), totalRecords); 7x^P 74
} 58Fan*fO
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/** ]?`t
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* the basic page utils not including exception =q(;g]e
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handler =5jX#Dc5.+
* @param everyPage _$?SK id|o
* @param currentPage (W|Eg
* @param totalRecords w#5^A(NR
* @return page S]3t{s#JW7
*/ y#Ao6Od6
publicstatic Page createPage(int everyPage, int C0X_t
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currentPage, int totalRecords){ )q\|f_
everyPage = getEveryPage(everyPage); TC4W7}}
currentPage = getCurrentPage(currentPage); a8Jn.!
int beginIndex = getBeginIndex(everyPage, +tNu8M@xFo
>?q()>l
currentPage); kmm1b (
int totalPage = getTotalPage(everyPage, &JM|u ww?1
LuB-9[^<
totalRecords); /,z4tf
boolean hasNextPage = hasNextPage(currentPage, R*D0A@
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totalPage); ~JsTHE$F
boolean hasPrePage = hasPrePage(currentPage); Ax4nx!W,
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returnnew Page(hasPrePage, hasNextPage, ?1Lzbou
everyPage, totalPage, sHSZIkB-r
currentPage, 5uuZ t0V\
hGx)X64Mw
beginIndex); ((TiBCF4
} 8C2s-%:
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privatestaticint getEveryPage(int everyPage){ Lmx95[#@a
return everyPage == 0 ? 10 : everyPage; _
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} W|o LS
mVN^X/L(y
privatestaticint getCurrentPage(int currentPage){ i:wTPR
return currentPage == 0 ? 1 : currentPage; NZSP*# !B
} lz?F ,].
4
e1=b,
privatestaticint getBeginIndex(int everyPage, int &
Me%ZM0
'Jww}^h1
currentPage){ e.%`
tK3J
return(currentPage - 1) * everyPage; K%ltB&
} mYf7?I~
"k(Ee
privatestaticint getTotalPage(int everyPage, int F'DO46
X|)Ox
,(
totalRecords){
g-MaP
int totalPage = 0; hmv"|1Sa!~
gN|[n.W4
if(totalRecords % everyPage == 0) A"8`5qa
totalPage = totalRecords / everyPage; ,c#=qb8""
else 8*;88vW"2
totalPage = totalRecords / everyPage + 1 ; Cvr?%+)$M
q$Z.5EN
return totalPage; 2XubM+6
} 8r7~ >p~
2B{~"<
privatestaticboolean hasPrePage(int currentPage){ tY^ MP5*
return currentPage == 1 ? false : true; <J4|FOz!=
} L$^ya%2
wiXdb[[#
privatestaticboolean hasNextPage(int currentPage, 8_6\>hW&
e#MEDjm/)g
int totalPage){ S+G!o]&2
return currentPage == totalPage || totalPage == C~F do0D
p}%T`e=Z9
0 ? false : true; 01VEz
8[\
} p.kJNPO\@
#E%0 o
LwQq0<v
} r]p
0O(
*6oQW
m0+X 109
:|3n`,
SnsOuC5Ah
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。 kYBy\
t(YrF,
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 j^
VAA\
i#o:V/Z.
做法如下: zrWkz3FN
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 T >XnVK
Zi5d"V[}T
的信息,和一个结果集List: IKx]?0sS
java代码: / E~)xgPM<
G j^J pG
:feU
/*Created on 2005-6-13*/ bM[!E 8dF
package com.adt.bo; Ergh]"AD6-
Y;ytm
#=
import java.util.List; BFP (2j
f$vWi&(
import org.flyware.util.page.Page; 9~ 8 A>
f>\guuG
/** C'mYR3?m;
* @author Joa 5}d"nx
*/ gPs%v`y)*D
publicclass Result { 7p'L(dq
bi`{ k\3A
private Page page; |F_Z
,f
..46G
private List content; /,v>w,
wg<UCmfu!
/** %$K2$dq5
* The default constructor
"LyMw){
*/ H4[];&]xr
public Result(){ DK8eFyG^2
super(); AnK-\4
} 5g9lO]WDI
4FK|y&p4r
/** $89hkUuTu^
* The constructor using fields $^|I?5xD
* *7: )k
* @param page bvY'=
* @param content EugQr<sM#
*/ X=O}k&
public Result(Page page, List content){ /5 rWcX
this.page = page; tmM8YN|
this.content = content; thWQU"z4
} Hgs=qH
z8W@N8IqC
/** KUs\7Sb
* @return Returns the content. 3KFw0(S/
*/ >iefEv\
publicList getContent(){ 1T(:bM_t`7
return content; Wez"E2J`
} ?M'_L']N[
x2gnB@t
/** /">A3bq
* @return Returns the page. -:92<G\D
*/ H"hL+F ^
public Page getPage(){ gY'w=(/`
return page; VO"f=gFg
} ub^v,S8O
3m1]Ia-9
/** ~9#nC`%2j
* @param content P} =eR
* The content to set. |)'gQvDM
*/ a o_A%?Ld
public void setContent(List content){ lLD-QO}/
this.content = content; nNe`?TS?f
} B{IYVviiP
7gIK+1`
/** jA ?tDAx`
* @param page Fa]fSqy@;
* The page to set. 'M"JF;*r
*/ E]x)Qr2Ju
publicvoid setPage(Page page){ hVQ
TW[
this.page = page; = ~{n-rMF
} Sb_T _m
} nv WTx4oy
yP :/F|E$
7/*a
n7UZ&ab
Qg]8~^Q<
2. 编写业务逻辑接口,并实现它(UserManager, nsChNwPX
W)rE_tw,|
UserManagerImpl) z0ULB?*"
java代码: u+7B-l=u*
YLc 2:9
,/V'(\>
/*Created on 2005-7-15*/ EA )28]Y.
package com.adt.service; _H#l&bL@C
J)6A,:wt
import net.sf.hibernate.HibernateException; "m^whHj
[kc%+j<g
import org.flyware.util.page.Page; z?C;z7eT
p)M\q fZ
import com.adt.bo.Result; 6 isz
~r`~I"ZK7^
/** f@roRn8p?
* @author Joa XxT7YCi
*/ Bsm>^zZ`YU
publicinterface UserManager { $)OUOv
mi~BdBv
public Result listUser(Page page)throws 79J@`
0(9]m)e
HibernateException; N7lWeF
yKR0]6ahA
} Pw4j?pv2
p_hljgOV
t(SSrM]
;d17xu?ks
t
>89(
k
java代码: 1c=Roiq
xJ"CAg|B
{.7ve<K
/*Created on 2005-7-15*/ o^59kQT
package com.adt.service.impl; =m@5$
f3h&K}x
import java.util.List; \R&4Nu2F
ns.[PJ"8
import net.sf.hibernate.HibernateException; "P:kZ=M
Q
s^_E'j$
import org.flyware.util.page.Page; }`/wj
import org.flyware.util.page.PageUtil; )N
QtjB$
h3^&,U
import com.adt.bo.Result; -la~p~8
import com.adt.dao.UserDAO; U:]b&I
import com.adt.exception.ObjectNotFoundException; q?C)5(
import com.adt.service.UserManager; K7&A^$`
xNt
/** 1m-"v:fT5D
* @author Joa lu@#)
*/ H~~I6D{8
publicclass UserManagerImpl implements UserManager { Ty]/F+{
!=#230Y
private UserDAO userDAO; #&\hgsw/T
tK&.0)*=
/** )2X ng_,
* @param userDAO The userDAO to set. X-di^%<
*/ ZyqTtA!A
publicvoid setUserDAO(UserDAO userDAO){ JL1%XQ
i
this.userDAO = userDAO; }z&P^p)R
} Y[8w0ve-g
J.x>*3<l
/* (non-Javadoc) D5X;hd
* @see com.adt.service.UserManager#listUser 5* 1wQlL
1r}fnT<
(org.flyware.util.page.Page) =+gp~RR,
*/ T6f{'.w
public Result listUser(Page page)throws t#|E.G:=
]?F05!$ *
HibernateException, ObjectNotFoundException { JH!qGV1
int totalRecords = userDAO.getUserCount(); _C?<re3*
if(totalRecords == 0) |7Z,z0 ?V
throw new ObjectNotFoundException >vg!<%]W]
9/w'4bd
("userNotExist"); YgaJ*%\
page = PageUtil.createPage(page, totalRecords); Co8b0-Z
List users = userDAO.getUserByPage(page); 5| 2B@6-
returnnew Result(page, users); zY8"\ZB
} ~MY7Ic%
aDa}@-F&a
} o}5:vi]
Yfy6o6*:
8xmw-s)
#&">x7?5
yz-IZt(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 sZ-]yr\E"
=S@$"_&
询,接下来编写UserDAO的代码: G*BM'^0+
3. UserDAO 和 UserDAOImpl: 1G|Q~%cv
java代码: XzQ=8r>l
@.kv",[{[
8aGZ% UI
/*Created on 2005-7-15*/ ?{q w
/&
package com.adt.dao; vnz.81OR
t; n6Q0
import java.util.List; h`%K\C
14\%2nE
import org.flyware.util.page.Page; .]Z M2
{mL/)\
import net.sf.hibernate.HibernateException; OR a!84L
&F\J%#{
/** 9G_=)8sOV
* @author Joa `.%;|"xR
*/ d8M"vd
publicinterface UserDAO extends BaseDAO { ,?B.+4CW\E
^iubqtT]
publicList getUserByName(String name)throws "<6pp4*I
[RD ^@~x
HibernateException; !gy'_Y
Hi|2z5=V
publicint getUserCount()throws HibernateException; <Xy8}Z`s
L5yxaF{]
publicList getUserByPage(Page page)throws N(&FATZUW
N l_!%k:
HibernateException; qx{.`AaZW
&7Ixf?e!K
} `#fOY$#XB
_DC/`_'
g)$Pvfc
joDfvY*[
6Ep ns s
java代码: =[{Pw8['
q22cp&gmX
Hh;w\)/%j
/*Created on 2005-7-15*/ }U'5j/EFZ
package com.adt.dao.impl; V-=$:J"J'\
5F2+o#*h
import java.util.List; vkq?z~GA
/N%f78
Z
import org.flyware.util.page.Page; uc Z(D|a
?
z=>n
import net.sf.hibernate.HibernateException; =AL95"cH~
import net.sf.hibernate.Query; *{4cc
<O5;w
import com.adt.dao.UserDAO; RMC|(Q<
6xL=JSi~
/** 0y;&L63>T
* @author Joa #j-,#P@
*/ g#[9O'H
public class UserDAOImpl extends BaseDAOHibernateImpl `8FC&%X_
]Jnf.3
implements UserDAO { YGWb!|Z$
+1d\ZZA|6&
/* (non-Javadoc) ?qO,=ms>-
* @see com.adt.dao.UserDAO#getUserByName YfMe69/0I
hQL9 Zl~
(java.lang.String) puqLXDjA/
*/ :VN<,1s9p^
publicList getUserByName(String name)throws Od&M^;BQ
WKah$l
HibernateException { nNhN:?
String querySentence = "FROM user in class Z$zUy|s[
$elrX-(vL
com.adt.po.User WHERE user.name=:name"; R8'yQ#FVy
Query query = getSession().createQuery
"rX=G=
f{AgKW9"
(querySentence); ,dVCbAS@
query.setParameter("name", name); (la<X<w
return query.list(); hsqUiB tc6
} W$'pUhq\H
C9=f=sGL
/* (non-Javadoc) J $e.$ah;
* @see com.adt.dao.UserDAO#getUserCount() K,IOD
t
*/ N7oMtlvL[w
publicint getUserCount()throws HibernateException { J~_p2TZJ\3
int count = 0; yQi|^X~?$
String querySentence = "SELECT count(*) FROM p1?}"bHk
3~cOQ%#]4
user in class com.adt.po.User"; A^K,[8VX
Query query = getSession().createQuery M%B[>pONb7
l m
(querySentence); e-e{-pB6
count = ((Integer)query.iterate().next 5)nv
/t>o
-
()).intValue(); EPa3Yb?BGb
return count; |nicvg@
} 5ef&Ih.3
k oHY
AF
/* (non-Javadoc) @\"*Z&]8z0
* @see com.adt.dao.UserDAO#getUserByPage 4|2$b:t
BPG)m,/b
(org.flyware.util.page.Page) 3Aj_,&X.@(
*/ c%Gz{':+
publicList getUserByPage(Page page)throws zr[~wM
19N:9;Ixz
HibernateException { xJ"Zg]d{
String querySentence = "FROM user in class /ruf1?\,R
6~!YEuA
com.adt.po.User"; wP8R=T
Query query = getSession().createQuery <`r+l5
KPR{5
(querySentence); *z+\yfOO"
query.setFirstResult(page.getBeginIndex()) :?UIyN?
.setMaxResults(page.getEveryPage()); J,D{dYLDD
return query.list(); gx6&'${=#
} `+f\Q2]Z
_yoG<qI
} v
PGuEfz
K[kmfXKu
GDcV1$NA
)_Oc=/c|f
z5vryhX_Z
至此,一个完整的分页程序完成。前台的只需要调用 EmUxM_T/2
7q^/.:wlf
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z~c7r n
^=W&p%Y(!
的综合体,而传入的参数page对象则可以由前台传入,如果用 :9`1bZ?a
IWWFl6$-
webwork,甚至可以直接在配置文件中指定。 kdHql>0
f9 Xw]G9
下面给出一个webwork调用示例: %om7h$D=`
java代码: E1C8yIF
> Qtyw.n
.lFSFJ ??
/*Created on 2005-6-17*/ IRU2/Y cg
package com.adt.action.user; R/wSGP`W
s{,e^T
import java.util.List; /,>.${,;u
X<QE]RZ
import org.apache.commons.logging.Log; J6%op{7/
import org.apache.commons.logging.LogFactory; 9@1W= sl
import org.flyware.util.page.Page; ~>C >LH>8
*Qf}4a0
import com.adt.bo.Result; 7wqwDE
import com.adt.service.UserService; #NE^f2
import com.opensymphony.xwork.Action; *Vc=]Z2G^
.Ep3~9TBW
/** lC4By,1*
* @author Joa -Q@d
*/ :$tW9*\KY
publicclass ListUser implementsAction{ "n
e'iJf_(
G6,8Xwk
privatestaticfinal Log logger = LogFactory.getLog MYPcH\K$h
.UYpPuAkn
(ListUser.class); w7D:0SGD
6,)y{/ENC
private UserService userService; CIDL{i8
4eEs_R
private Page page; &\H5*A.HkA
=z/F=1^<
privateList users; 1P[Lz!C
OKqpc;y:D
/* &wuV}S7
* (non-Javadoc) %aKkk)s
* "qsNySI
* @see com.opensymphony.xwork.Action#execute() {_~G+rqY
*/ GWVdNYpmr
publicString execute()throwsException{ d!t@A
Result result = userService.listUser(page); (FaT{W{
page = result.getPage(); H_j<%VW
users = result.getContent(); _+N^yw ,r*
return SUCCESS; Pc7:hu
} [5VUcXGt*\
1IV
0a
/** o.5j@dr
* @return Returns the page. /wTf&_"mTL
*/ a
98
public Page getPage(){ F^YIZ,=p!
return page; ]~^/w}(K
} lnDDFsA
s=TjM?)
/** 'oz={;
* @return Returns the users. aAri
*/ /;rN/ot2o
publicList getUsers(){ 32iI :u
return users; JF*g!sV%
} >, E$bm2
9+QrTO
/** 5E!m! nBZ
* @param page B`scuLl3
* The page to set. Zir`IQ$
*/ SR&
mHI-f0
publicvoid setPage(Page page){ skz]@{38
this.page = page; F}]_/cY7B
} Q:O>k CDV
RfBb{?PP)
/** |y%].y)
* @param users ~TH5>``;gF
* The users to set. ql~{`qoD~
*/ Z0eBx
publicvoid setUsers(List users){ z#VpS=
this.users = users; +Rgw+o
} $NT9LtT@K
i)L:VkN
/** i grog
* @param userService X|`,AKJit
* The userService to set. "Y]ZPFh#.
*/ EQ7n'Wqq
publicvoid setUserService(UserService userService){ 5j,qAay9
this.userService = userService; q|X4[E|{Q
} qffSq](D.
}
f_!`~`04
L~{Vt~H9"
Qe$>Jv5
!><
%\K
r`&|)Hx
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, yim$y,=d
50ew/fZj|
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 aNC,ccm
:bRR(sP
么只需要: Kk>qgi$
java代码: Ue#yDTjc
=Rx?6%
J,G9m4Z7
<?xml version="1.0"?> {7Avba
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork P! Ed
/iy*3P,`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- c^Jgr(Ow
0@K:Tq-mF
1.0.dtd"> m"(d%N7
{[5L96RH%
<xwork> SP*JleQN
@CU|3Qg
<package name="user" extends="webwork- 4spaw?j
nRB>[lG
interceptors"> 4l}M
i
iW@Vw{|i I
<!-- The default interceptor stack name yVI;s|jG
tOg
8L2
--> i!W8Q$V
<default-interceptor-ref p/1}>F|i
V$<G)dwUG5
name="myDefaultWebStack"/> %?oU{KzQ@;
Z4AAg
<action name="listUser" //M4Sq(
:aq>
class="com.adt.action.user.ListUser"> /QXs-T}d
<param aE\BAbD7
?4>y2!OC9
name="page.everyPage">10</param> Bdq"6SK>
<result cL)rjty2
c =N]!
,MO
name="success">/user/user_list.jsp</result> bEQtVe@`
</action> @=0r3
V2s}<uG
</package> gQh Ccv
reM
</xwork> cF&h$4-
rrY{Jf9>
H'0*CiHes
Kt90mA
k<'vP{
/GuSIZg"_
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ;2Ad])
ju^"vw
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 5Vqmv<F;$Z
*[xNp[4EU
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;WS7.
QR5,_wJ&
(: TGe v
sMfFm@\ N
K"k"ml<4E
我写的一个用于分页的类,用了泛型了,hoho ]PzTl {]
r$r&4dY
java代码: c_z/At;4
L_gsG|xX
aC,vh1")F
package com.intokr.util; 0"kE^=
e.}3OK
import java.util.List; LD~Jbq
`F2*o47|t
/** 3_oD[ ])A
* 用于分页的类<br> {"0TO|%x
* 可以用于传递查询的结果也可以用于传送查询的参数<br> siRnH(^J
* Jl>at
* @version 0.01 D){"fw+b
* @author cheng 2[LX\
*/ gl9pgY1ni
public class Paginator<E> { @r/Id{pCI
privateint count = 0; // 总记录数 M8?#%x6;N
privateint p = 1; // 页编号 urrO1
privateint num = 20; // 每页的记录数 u_4:#~b
privateList<E> results = null; // 结果 ?b@q5Y
*H%0Gsk
/** 6>=-/)p}
* 结果总数 %%as>}.
*/ ?K4.L?D#J
publicint getCount(){ I[g?Ju >
return count; AY&9JSu6
} =MJ-s;raq
8L7Y
A)u
publicvoid setCount(int count){ V/(`Ek-
this.count = count; AJ>BF.>
} Th~3mf
#
4aalhy<j
/** 1=/doo{^
* 本结果所在的页码,从1开始 #Z|%0r_~
* !Bk[p/\
* @return Returns the pageNo. E?Qz/*'zv
*/ )]/i
publicint getP(){ Som.
qD
return p; [ GR|$/(z=
} ~jp!"f
+H[}T ]
/** s`Yu"s
8}4
* if(p<=0) p=1 iJ`%yg,
* qXrt0s[
* @param p #JL&]Z+X6
*/ A;fB6
publicvoid setP(int p){ -YzQ2#K
if(p <= 0) l$k]O
p = 1; vLv|SqD
this.p = p; yN 9$gfJC^
} <OR.q
MPKpS3VS
/** Gg=aK~q6
* 每页记录数量 ldAov\X
*/ L,C? gd@"
publicint getNum(){ aPD?Bh>JU
return num; !paN`Fz\a
} .N5hV3
s6uF5]M;2
/** )|U_Z"0H^
* if(num<1) num=1 cy=I0
*/ 7oZ@<QP'
publicvoid setNum(int num){ nd $H
3sf
if(num < 1) |~@x4J5,
num = 1; --in+
this.num = num; C2+{U
} ?(5o@Xq
U6c)"^\
/** j>$=SMc
* 获得总页数 pau*kMu^}
*/ tJUVw=
publicint getPageNum(){ {E3xI2
return(count - 1) / num + 1; Ne &Xf
} o,?!"*EP
]regi- LGU
/** DAjG*K{
* 获得本页的开始编号,为 (p-1)*num+1 +"k.E
x0:
*/ v2/yw,
publicint getStart(){ gHQPhe#n
return(p - 1) * num + 1; .abyYVrN4?
} /hm84La
u:_sTfKm&
/** 'ox0o:
* @return Returns the results. [kPD`be2#
*/ QuSV&>T\
publicList<E> getResults(){ 8g<Q5(
return results; ?!bd!:(N
} vC)"*wYB{
X}zX`]:I'
public void setResults(List<E> results){ Pv< QjY
this.results = results; M0cd-Dn
} TA Ftcs:
~gu=x&{
public String toString(){ I*^5'N'
StringBuilder buff = new StringBuilder siZr@g !L
KKLR'w,A>
(); ]YCPyc:
buff.append("{"); W*YxBn4
buff.append("count:").append(count); lemVP'cn
buff.append(",p:").append(p); &}vR(y*#c
buff.append(",nump:").append(num); h7bPAW=(
buff.append(",results:").append EfFz7j&X
Yuwc$Qp)
(results); 7#~4{rjg
buff.append("}"); |w=Ec#)t4
return buff.toString(); S-isL4D.Z
} nY OY"'z
rei
8LW
} n4^~gT%b5]
L<bYRGz
J"diFz+20