Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mQ9shdvt-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bfYVA2=Z
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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 L-zU%`1{M
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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 tKds|0,j|
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分页支持类: /SyAjZ
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java代码: Ggy?5N7P
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package com.javaeye.common.util; &VcO,7 A|
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import java.util.List; b$- g"F
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publicclass PaginationSupport { igEqty!.
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publicfinalstaticint PAGESIZE = 30; M#Q"h5l
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privateint pageSize = PAGESIZE; G[u{! 2RS
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privateList items; d[nz0LI|mk
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privateint totalCount; b *3h}n;
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privateint[] indexes = newint[0]; Ocn@JOg
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privateint startIndex = 0; +}Mm5^6*
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public PaginationSupport(List items, int AYfe_Dj
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totalCount){ BuUM~k&SY
setPageSize(PAGESIZE); T0.sL9
setTotalCount(totalCount); m=Mk@xfQ#
setItems(items); o 9(x\g
setStartIndex(0); j8]M}Q$
} P>$+XrTE
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public PaginationSupport(List items, int hh2&FI
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totalCount, int startIndex){ [nlq(DGJhp
setPageSize(PAGESIZE); K<%8.mZ7
setTotalCount(totalCount); Lr(JnS
setItems(items); ="PFCxi
setStartIndex(startIndex); XqwP<5Z
} .F[5{XV
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public PaginationSupport(List items, int P0U&+^W"9
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totalCount, int pageSize, int startIndex){ C~'.3Q6
setPageSize(pageSize); ?^LG>GgV
setTotalCount(totalCount); d`%7Pk
setItems(items); b!teSf
setStartIndex(startIndex); .[1@wW&L
} *P&lAyt6
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publicList getItems(){ 8dJ+Ei~M
return items; GiXs`Yt|
} N9M",(WTt}
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publicvoid setItems(List items){ madbl0[y.
this.items = items; |34w<0Pc,
} {xTh!ih2-
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publicint getPageSize(){ "
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return pageSize; !lA~;F
} *y$CDv
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publicvoid setPageSize(int pageSize){ 3C'6i
this.pageSize = pageSize; $vn)(zn+
} Bgp%hK
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publicint getTotalCount(){ ~y
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return totalCount; ] ;HCt=I~
} oZdY0n h4
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publicvoid setTotalCount(int totalCount){ ZS`Kj(D
if(totalCount > 0){ 8o.|P8%
this.totalCount = totalCount; =H}x
int count = totalCount / c>Ri6=C
=Lnip<t>ja
pageSize; sM%l:Fv
if(totalCount % pageSize > 0)
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count++; qv|}>wU
indexes = newint[count]; 6$zd2N?
for(int i = 0; i < count; i++){ ,DEcCHr,
indexes = pageSize * 563ExibH
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8
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} VN$7r
}else{ .CNwuN\
this.totalCount = 0; Dd-a*6|x
} Uv~|Xj4.
} mHJGpJ=a-
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publicint[] getIndexes(){ 5fz
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return indexes;
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} AVfF<E/
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publicvoid setIndexes(int[] indexes){ Y]5MM:mI
this.indexes = indexes; `)MKCw$e
} T[c-E*{hR
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publicint getStartIndex(){ Y^;izM}
return startIndex; z\?<j%e!t
} rfzzMV
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publicvoid setStartIndex(int startIndex){ ;E>#qYC6
if(totalCount <= 0) LB9W.cA
this.startIndex = 0; T21?~jS
elseif(startIndex >= totalCount) `0MQL@B
this.startIndex = indexes p _3xW{I
zJ:%iL@
[indexes.length - 1]; xuVc1jJH
elseif(startIndex < 0) 17 0r 5
this.startIndex = 0; 7#7|+%W0
else{ rp2g./2
this.startIndex = indexes !\O!Du
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[startIndex / pageSize]; 7KJ0>0~Et
} ={;+0Wjb8
} r:4]:NKCi
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publicint getNextIndex(){ ?{5}3abB`
int nextIndex = getStartIndex() + X|QokAR{$>
.])X.7@x
pageSize; :VLYF$|
if(nextIndex >= totalCount) Q/*|ADoq
return getStartIndex(); 1+Ik\
else VUz+_)
return nextIndex; FN (O
} -(ST
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publicint getPreviousIndex(){ tF./Jx]_
int previousIndex = getStartIndex() - pF8+<
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pageSize; G%=
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if(previousIndex < 0) (hIo0.
return0; 9wO2`e )
else /N obS'd
return previousIndex; fL]jk1.Xv-
} ]^i^L
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} E\cX
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抽象业务类 Np+pJc1
java代码: uY/CiTWr
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/** _={mKKoHs
* Created on 2005-7-12 3TS:H1n
*/ D,(:))DmR
package com.javaeye.common.business; ,ei=w,O
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import java.io.Serializable; %=\*OIhl
import java.util.List; e$JATA:j
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import org.hibernate.Criteria; _#{qDG=
import org.hibernate.HibernateException; XdOntP *a
import org.hibernate.Session; WW!-,d{{@
import org.hibernate.criterion.DetachedCriteria; DZEq(>mn
import org.hibernate.criterion.Projections; #uCfXJ-
import D";clP05K
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org.springframework.orm.hibernate3.HibernateCallback; .WuSW[g
import v-Q>I5D;:
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org.springframework.orm.hibernate3.support.HibernateDaoS )e6sg]#
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upport; {MDM= ;WP_
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import com.javaeye.common.util.PaginationSupport; 0[N1SY\lj
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public abstract class AbstractManager extends xe3Jxo!U
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HibernateDaoSupport { 1rLxF{,
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privateboolean cacheQueries = false; d 3#e7rQ8
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privateString queryCacheRegion; lQm7`+
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publicvoid setCacheQueries(boolean )V*`(dn'zm
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cacheQueries){ T1x67 b
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this.cacheQueries = cacheQueries; CJs
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} {G<1.
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publicvoid setQueryCacheRegion(String -9o7a_Z
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queryCacheRegion){ K,*-Y)v2W
this.queryCacheRegion = R|Uu
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queryCacheRegion; _u6MSRX[6$
} `gJ$fTi&
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publicvoid save(finalObject entity){ e#F3KLSL`
getHibernateTemplate().save(entity); 6BEDk!
} MIWc
@.i2
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publicvoid persist(finalObject entity){ s|TO9N)pO
getHibernateTemplate().save(entity); }"v#_vJfz7
} >}JEX]V
}LLQ+
publicvoid update(finalObject entity){ 5 [4{1v
getHibernateTemplate().update(entity); Re'3 bs:+
} soX^$l
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publicvoid delete(finalObject entity){ ^<
getHibernateTemplate().delete(entity); *Gj`1#Z$
} Z,M2vRj"qT
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publicObject load(finalClass entity, 8|5+\1!#/)
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finalSerializable id){ 3 +`,'Q9
return getHibernateTemplate().load fRkx ^u
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(entity, id); ej=}OH4
} :
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publicObject get(finalClass entity, roe_H>
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finalSerializable id){ B[+b%a3
return getHibernateTemplate().get u^WZsW
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(entity, id); /ZH* t \
} NJOV!\k
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publicList findAll(finalClass entity){ TB84}
return getHibernateTemplate().find("from QA)W( 1
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" + entity.getName()); .1ep8O<
} dX[Xe
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publicList findByNamedQuery(finalString r/HG{XH`
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namedQuery){ \nL@P6X
return getHibernateTemplate cHVu6I?h
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().findByNamedQuery(namedQuery); .SOCWznb
} |W&K@g$
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publicList findByNamedQuery(finalString query, z=8l@&hYLq
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finalObject parameter){ yD8Qy+6L
return getHibernateTemplate \{ C
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q^<;B Y
().findByNamedQuery(query, parameter); :R$v7{1
} XIl#0-E0X
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publicList findByNamedQuery(finalString query, x`'s
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finalObject[] parameters){ 47A[-&y*X
return getHibernateTemplate j)juvat
fWF!% |L
().findByNamedQuery(query, parameters); s!Iinc^p
} h///
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publicList find(finalString query){ I7t}$S6
return getHibernateTemplate().find Lw?>1rTT/
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(query); gI@nE:(m
} Z uP3/d
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publicList find(finalString query, finalObject TY` R_
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parameter){ gb[.Ww
return getHibernateTemplate().find \\d8ulu
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(query, parameter); A-$C6q
} pF}E`U=Z
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public PaginationSupport findPageByCriteria 5p3:8G7
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(final DetachedCriteria detachedCriteria){ $d&7q5[
return findPageByCriteria 9,"gXsvx(
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >gn@NJ2 N
} !!Yf>0u#
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public PaginationSupport findPageByCriteria <YCR^?hJSi
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(final DetachedCriteria detachedCriteria, finalint =OKUSHu@V
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startIndex){ 7&L8zl|K
return findPageByCriteria >Tn[CgH]7
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(detachedCriteria, PaginationSupport.PAGESIZE, S>"C}F$X
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startIndex); @ W q8AFo
} UyF;sw
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public PaginationSupport findPageByCriteria x'%vL",%
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(final DetachedCriteria detachedCriteria, finalint !&v"+ K3lU
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pageSize, |;U3pq)
finalint startIndex){ eV0eMDY5
return(PaginationSupport) ?tT89m3_E
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getHibernateTemplate().execute(new HibernateCallback(){ 8|\xU9VT
publicObject doInHibernate Y$qjQ 1jF+
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(Session session)throws HibernateException { 1D~B\=LL}
Criteria criteria = 'w|N}
4
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detachedCriteria.getExecutableCriteria(session); s(MdjWw
int totalCount = 90H/Txq
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((Integer) criteria.setProjection(Projections.rowCount \z.p [;'ir
.wtYostv
()).uniqueResult()).intValue(); zThut!O
criteria.setProjection e)F_zX
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;[;
(null); ItAC=/(d
List items = w7<4D,hk
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criteria.setFirstResult(startIndex).setMaxResults ^[2siG
]Rmu+N|
(pageSize).list(); :/}=s5aQl/
PaginationSupport ps = =knBwjeD
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new PaginationSupport(items, totalCount, pageSize, HDs8 M
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startIndex); *kJa$3*r
return ps; |Y(
} ,%y!F3m
}, true); Jf@Xz7{z
} q+lCA#Sx
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public List findAllByCriteria(final Jp~[Dm
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DetachedCriteria detachedCriteria){ RF\h69]:I
return(List) getHibernateTemplate M%Q_;\?]
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().execute(new HibernateCallback(){ [-#q'S
publicObject doInHibernate _IvqZ/6Y(
cZw_^@!
(Session session)throws HibernateException { 2d&HSW
Criteria criteria = >R\!Qk
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detachedCriteria.getExecutableCriteria(session); 8%b-.O:_$
return criteria.list(); YsRq.9Mr
} /T 4GPi\lg
}, true); VB4ir\nF
} t & 5s.
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public int getCountByCriteria(final N,ZmGzNP)
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DetachedCriteria detachedCriteria){ krXU*64
Integer count = (Integer) u>2opI~m
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getHibernateTemplate().execute(new HibernateCallback(){ 9}d^ll&
publicObject doInHibernate TZObjSm_v
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(Session session)throws HibernateException { !@
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Criteria criteria = 2W)KfS
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detachedCriteria.getExecutableCriteria(session); -TyBb]
return {ka={7
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criteria.setProjection(Projections.rowCount =%;TVJk*a
}y%mG&KSz
()).uniqueResult(); `>k7^!Ds
}
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}, true); QEY#U|
return count.intValue(); byIP]7Ld
} {\
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} "s\himoa
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用户在web层构造查询条件detachedCriteria,和可选的 &LhR0A
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -.UUa
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PaginationSupport的实例ps。 u9ue>I/
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ps.getItems()得到已分页好的结果集 OUm,;WNLf
ps.getIndexes()得到分页索引的数组 F'njtrO3
ps.getTotalCount()得到总结果数 sfCU"O2G
ps.getStartIndex()当前分页索引 ^<Sy{KY
ps.getNextIndex()下一页索引 Gg5>~"pb
ps.getPreviousIndex()上一页索引 .[vYT.LE
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0C0ld!>r
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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 Jrx]/CM
^:o^g'Yab
一下代码重构了。 DA/\[w?J
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我把原本我的做法也提供出来供大家讨论吧: =UZm4=T
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首先,为了实现分页查询,我封装了一个Page类: OJ)XJL
java代码: Cvtz&dH
iZ2nBiQ
R|!4klb
/*Created on 2005-4-14*/ N-Sjd%Z
package org.flyware.util.page; OH vV_
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/** m2to94yh
* @author Joa gg
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* "'U]4Z%q!
*/ ~P+;_
publicclass Page { iiV'-!3w
DbH'Qs?z
/** imply if the page has previous page */ WL1$LLzN
privateboolean hasPrePage; mUwGr_)wj
X%Ta?(9|.^
/** imply if the page has next page */ w;V+)r?w
privateboolean hasNextPage; ^e1mK4`
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/** the number of every page */ s^-o_K\*c
privateint everyPage; o1rH@ D6/-
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/** the total page number */ 5m
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privateint totalPage; EZ)GW%Bm2
+(##B pC
/** the number of current page */ wRQMuFGY
privateint currentPage; VJ|80?4h
M7\K iQd
/** the begin index of the records by the current wWB^m@:4
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query */ rA1;DSw6E[
privateint beginIndex; cK1RmL"3
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MF4B 2d
/** The default constructor */ r$;u4FR
public Page(){ MK, $#
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} %CG=mTP
*&rV}vVP^
/** construct the page by everyPage Mt(;7q@1c
* @param everyPage r_M5:Rz
* */ hE}y/A[
public Page(int everyPage){ 9I*`~il>{
this.everyPage = everyPage; `'/1Ij+
} >twog}%
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/** The whole constructor */ lxOUV? m^N
public Page(boolean hasPrePage, boolean hasNextPage, p!2t/XIM
tcj3x<
hg}R(.1K=
int everyPage, int totalPage, ~X1<x4P\
int currentPage, int beginIndex){ ^97\TmzP{
this.hasPrePage = hasPrePage; l =^ ^l`
this.hasNextPage = hasNextPage; -n`2>L1
this.everyPage = everyPage; .7MLgC;
this.totalPage = totalPage; NLO&.Q]#
this.currentPage = currentPage; MGSD;Lgn
this.beginIndex = beginIndex; 0`"DYJ}d
} RV, cQ K
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/** 9l:vVp7Uk
* @return K{]\}7+
* Returns the beginIndex. 17B`
*/ gYvT'72
publicint getBeginIndex(){ N1espc@j
return beginIndex; NIxtT>[+3
} #%SF2PB;
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/** 6ragRS/'x
* @param beginIndex G0pqiU6
* The beginIndex to set. A=pyaU`aE
*/ TvwkeOS#}7
publicvoid setBeginIndex(int beginIndex){ qM:*!Aq0g
this.beginIndex = beginIndex; A,! YXl[
} k= oCpXq^
s,;L6nX"
/** WEk3
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* @return ;q%V)4
* Returns the currentPage. PgwNE wG
*/ F]`_ak E
publicint getCurrentPage(){ Gque@u
return currentPage; </)QCl' d
} wVtBH_>
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/** 3d*wZ9qz
* @param currentPage :N
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* The currentPage to set. E sx`UG|
*/ $5Tjo
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publicvoid setCurrentPage(int currentPage){ yVb yw(gS
this.currentPage = currentPage; 38gEto#q
} nSeb?|$D 6
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/** }} wZ
* @return R'x^Y"
* Returns the everyPage. u4.2u}A/R%
*/ Q@? {|7:
publicint getEveryPage(){ gWHjI3;
return everyPage; {
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} ^F`\B'8MF
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/** @[w.!GW%
* @param everyPage P_%kYcX'
* The everyPage to set. rZ^VKO`~I1
*/ ,U#FtOec
publicvoid setEveryPage(int everyPage){ spv'r!*\ed
this.everyPage = everyPage; +]jJ: V
} 4+4C0/$Y
uE:`Fo=y
/** @8'LI8 \/
* @return iVqXf;eB!5
* Returns the hasNextPage. k{w
*/ QKtVwsz
+
publicboolean getHasNextPage(){ )SsO,E+t=U
return hasNextPage; #FsoK*F
} ,ku3;58O<
A!fRpN
/** X(fT[A_2C
* @param hasNextPage _"'0^F$I
* The hasNextPage to set. C &-]RffA
*/ Cy'! >
publicvoid setHasNextPage(boolean hasNextPage){ G.sf>.[
this.hasNextPage = hasNextPage; RL~]mI!U
} 6SN$El 0|G
NM&R\GI
/** &xMQ
* @return
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* Returns the hasPrePage. _Q6` Wp6m
*/ b<"LUM*;
publicboolean getHasPrePage(){ Jqgo\r%`
return hasPrePage; 5R/k8UZ
} b{hdEb
i@hW" [A
/** C{P:1ELYXH
* @param hasPrePage W"ldQ
* The hasPrePage to set. $>!tpJw
*/ \R (Yf!>
publicvoid setHasPrePage(boolean hasPrePage){ vN3uLz'<
this.hasPrePage = hasPrePage; [-'LJG Wb<
} T +~
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7=[/J*-m
/** ]O.Z4+6w
* @return Returns the totalPage. kCZxv"Ts
* Swnom?t
*/ V[baGNe
publicint getTotalPage(){ =Z}=n S?4
return totalPage; ,1|0]:
} 8/`ij?gn
<)ltvo(
/** i+eDBg6
* @param totalPage +DA,|~k_
* The totalPage to set. sRDxa5<MD
*/ 4&+lc*
publicvoid setTotalPage(int totalPage){ `/L D:R
this.totalPage = totalPage; TwLQ;Q
} 7bC)Co#:
{ K*
} ".Sa[A;~
1]]#HTwX
i :Sih"=
Nvj0MD{ X
rX@?~(^ML
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Spt;m0W90
+W[NgUrGJ
个PageUtil,负责对Page对象进行构造: 8$C?j\J|*
java代码: LGPPyKNx
LQ3J$N
^muPjM+D
/*Created on 2005-4-14*/ |tqYRWn0
package org.flyware.util.page; dPCn6
Rg6/6/ IN
import org.apache.commons.logging.Log; _1kcz]]F
import org.apache.commons.logging.LogFactory; u:GDM
6R+EG{`
/** wTkcR^
* @author Joa HA0Rv#p
* *zTEK:+_
*/ YH/3N(],
publicclass PageUtil { VAet!H +]
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privatestaticfinal Log logger = LogFactory.getLog '5
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't<hhjPqY
(PageUtil.class); #AUV&pI[
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/** _8'z"wF
* Use the origin page to create a new page _W^{,*p
* @param page 0;avWa)Q
* @param totalRecords wwVg'V;
* @return Z2^B.r#
*/ `=JGlN7
publicstatic Page createPage(Page page, int 6UnWtLE
O(CmdSk,
totalRecords){ a?P$8NLr
return createPage(page.getEveryPage(), Ze- MB0w
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page.getCurrentPage(), totalRecords); kcyT#'=j
} X;%*+xQ^
V.^Z)iNf^
/** uPQrDr5
* the basic page utils not including exception h&j9'
)R@M~d-o
handler *Ph@XkhU
* @param everyPage UcxMA%Pw7$
* @param currentPage >nOzz0,
* @param totalRecords +!Lz]@9K
* @return page iDrQ4>
*/ Y4)v>&H
publicstatic Page createPage(int everyPage, int .BjnV%l7Id
yi@mf$A|
currentPage, int totalRecords){ Kb,#Ot
everyPage = getEveryPage(everyPage); G0&'B6I>
currentPage = getCurrentPage(currentPage); Zq\Vq:MX
int beginIndex = getBeginIndex(everyPage, Q3|I.I e
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currentPage); h(MS>=
int totalPage = getTotalPage(everyPage, y~/i{a;1y
[y(AdZ0*
totalRecords); X Cf!xIv
boolean hasNextPage = hasNextPage(currentPage, `6QQS3fk!
l_z@.</8P@
totalPage); 6 Z7J<0
boolean hasPrePage = hasPrePage(currentPage); VH2/
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returnnew Page(hasPrePage, hasNextPage, L$4nbOu\~
everyPage, totalPage, (X( c.Jj
currentPage, <Z^qBM
ztHEXM.
beginIndex); ~zD*=h2C
} 7R5!(g
EGIwqci:
privatestaticint getEveryPage(int everyPage){ @(_f}SgfE
return everyPage == 0 ? 10 : everyPage; |?Bb{Es
} /woC{J)4p
<N}*|z7=b
privatestaticint getCurrentPage(int currentPage){ ![CF
>:e
return currentPage == 0 ? 1 : currentPage; ! tPHT
} o dTg.m
gt{$G|bi
privatestaticint getBeginIndex(int everyPage, int EaXDY<
ug.'OR
currentPage){ os~}5QJ
return(currentPage - 1) * everyPage; k:k!4
} BLQD=?Q
h(H b+7g
privatestaticint getTotalPage(int everyPage, int TVEFZ\p<A
Y~+`F5xX<
totalRecords){ 1?N$I}?
int totalPage = 0; dpI9DzA;
`.F+T)G
if(totalRecords % everyPage == 0) SdOE^_@:
totalPage = totalRecords / everyPage; U)y~{E~c34
else [V _?`M
totalPage = totalRecords / everyPage + 1 ; JHIXTy__
3PU'd^
return totalPage; 'p:L"L}Q?
} aq<QKnU
|y~un9j+
privatestaticboolean hasPrePage(int currentPage){ qs'ggF1
return currentPage == 1 ? false : true; b"QeCw#v`>
} ]53'\TH
ajMI7j^G
privatestaticboolean hasNextPage(int currentPage, PquATAzQA
@E5}v
int totalPage){ 1ps_zn(
return currentPage == totalPage || totalPage == x.-d>8-!]c
V|mz]H#|
0 ? false : true; b1 NB:
} 'I *&P5|
p&4#9I5
@mu2,%
} 6q]`??g.
KIfR4,=Q|
[H8QxJk
n]+v Eu|
}R]^%q @&
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 zA?]AL(+YW
b/dyH
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 06peo
d
Z/>0P* F
做法如下: *)H&n>"e
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Vn1hr;i]
Wr+1G 8
的信息,和一个结果集List: eg
vgi?y
java代码: _$Hx:^p:
%B{NH~
&?@5G
/*Created on 2005-6-13*/ wBK%=7
package com.adt.bo; 999E0A$dkv
F6h|AF|"
import java.util.List; ;r}>1LhN
3x{2Dh i
import org.flyware.util.page.Page; FTfejk!
U%,N"]`
/** o)hQ]d
* @author Joa 9BM 8
*/ &QQ8ut,;
publicclass Result { ;
3WA-nn
&^W91C?<6
private Page page; {Z=m5Dy}
Cw_XLMY%V1
private List content; (~<9\ZJs
6W abw:
/** 4z##4^9g
* The default constructor w
9mi2=
*/ '9#O#I&J
public Result(){ 3_]<H<w
super(); bkgJz+u
} P5*~Wi`
Ydr/ T/1
/** xE4iey@\}
* The constructor using fields *4tJ|m6"Y6
* CNiUHUD
* @param page xXktMlI
* @param content +s'qcC
*/ QQwD)WG
public Result(Page page, List content){ WhR j@y
this.page = page; h^D]@H
this.content = content; -^sbf.
} 9(/ ;Wutj"
Z $? Ql@M
/** dw
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* @return Returns the content. ]E+deM
*/ $rh {f<
publicList getContent(){ NZyGC
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return content; }(r%'(.6
} DPD%8a)?
07_ym\N
/** <6s?M1J
* @return Returns the page. BWct0=
*/ E .kjYIH8
public Page getPage(){ . .|>|X4
return page; 2y&m8_s-p
} Z/wKUK;
D{{ME8
/** %`P6a38j
* @param content R`F54?th
* The content to set. HCI|6{k
*/ xnW3,:0
public void setContent(List content){ \p-3P)U
this.content = content; |@x^5Ab$T
} to1{7q
>_Dq )n;%
/** D9;2w7v
* @param page DJ)z~W2I*
* The page to set. RN1q/H|
*/ Bw31h3yB
publicvoid setPage(Page page){ rSUarfZ<
this.page = page; GN4'LU
} K{}U[@_tS
} hy"O_Le
@,<@y>m7
_JZwd9K
W -Yv0n3
g{zvks~it
2. 编写业务逻辑接口,并实现它(UserManager, D~~&e<v'1
w~NQAHAvo
UserManagerImpl) =""z!%j
java代码: P9)E1]Dc$
Z.b}
iwnctI
/*Created on 2005-7-15*/ Zr0bVe+h
package com.adt.service; B>3joe}
|&+0Tg~ZE
import net.sf.hibernate.HibernateException; Fq6sl}b(On
Tl^9!>\Q
import org.flyware.util.page.Page; @O/Jy2>3H
5U&b")3IT!
import com.adt.bo.Result; oh
k.;
!1tHg Z2\
/** }7>r,
* @author Joa fb7Gy
*/ 8IY n9<L
publicinterface UserManager { Q`"gKBN1
QkXnXu
public Result listUser(Page page)throws 9Ij=~p]p
%T hY6y(
HibernateException; ]xlV;m
4!pMZ<$3
} }Km+5'G'U
cnQ;6LtFTz
c/Fy1Lv\
l,n0=Ew
jP?YV
java代码: T5; zgr
)~{T
QxRT%;'Zh]
/*Created on 2005-7-15*/ \Kp!G1?_AY
package com.adt.service.impl; lWr{v\L'
$TON`+lB
import java.util.List; [Bn C_^[W
UQ;ymTqdc
import net.sf.hibernate.HibernateException; ,m| :U
zo,`Vibx<
import org.flyware.util.page.Page; WoVPp*zlX
import org.flyware.util.page.PageUtil; M ABrf`<b
eI8rnp(Ia
import com.adt.bo.Result; DQ'=$z
import com.adt.dao.UserDAO; '->%b
import com.adt.exception.ObjectNotFoundException; >h^CC*&'pw
import com.adt.service.UserManager; u^DfRd&P0
LUGyc( h
/** DJxe3<
* @author Joa :DI``]Si\
*/ KMO(f!?
publicclass UserManagerImpl implements UserManager { n[~kcF
zn| S3c
private UserDAO userDAO; gnjh=anVX1
b&AGVWhh
/** `mar-r_m
* @param userDAO The userDAO to set. <L4.*
*/ ^I =W<
publicvoid setUserDAO(UserDAO userDAO){ ;D}8acQ
this.userDAO = userDAO; {MP8B'r-6
} lSGtbSyDI
pCXceNFo
/* (non-Javadoc) +Bg$]~T
* @see com.adt.service.UserManager#listUser Lnin;0~{
P9Yee!*H
(org.flyware.util.page.Page) CH!>RRF
*/ S$ u`)BG):
public Result listUser(Page page)throws Wpgp YcPS
HeV6=
HibernateException, ObjectNotFoundException { @>>8CU^~
int totalRecords = userDAO.getUserCount(); :@BAiKa[wa
if(totalRecords == 0) G(g`>' m
throw new ObjectNotFoundException BE`{? -G
eI?|Ps{S
("userNotExist"); [1+ o
page = PageUtil.createPage(page, totalRecords); [BPK0
List users = userDAO.getUserByPage(page); 4R 9lA
returnnew Result(page, users); `/W6,]
} v|IPus|>
_Xs(3V@'}
} Q"o* \I
Z>0a?=1[
&J>XKO nl
lD`@{A
O*;$))<wX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 mGss9eZa
]!@z3Hv3
询,接下来编写UserDAO的代码:
rG#o*oA
3. UserDAO 和 UserDAOImpl: )uj:k*`)
java代码: C[E[|s*l
6j*L]Sc
>K|<hzZ
/*Created on 2005-7-15*/ :Ma=P\J
W
package com.adt.dao; ORVFp]gG
c[p>*FnP
import java.util.List; =t[hs l
nK95v}p}Y
import org.flyware.util.page.Page; Gi=sJV
Ue:LKK1Gsr
import net.sf.hibernate.HibernateException; vBFMne1h
y
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/** M)m(
* @author Joa ;iol 2
*/ 29a~B<e7s
publicinterface UserDAO extends BaseDAO { %pikt7,Z~
(8JL/S;Z$
publicList getUserByName(String name)throws Lek!5Ug
7D5[
L
HibernateException; 2O|jVGap5x
f*Z8C9)
publicint getUserCount()throws HibernateException; OTgctw1s
UY(pKe>
publicList getUserByPage(Page page)throws 8C,}nh
y7f,]<%e_
HibernateException; tu4-##{
E#?Bn5-uBs
} xqZZ(jZ
}PC_qQF
ID{62>R
}s9eRmJs
V-1H(wRu
java代码: 5|nT5oS
4q9+a7@
Yz%A Kp
/*Created on 2005-7-15*/ ":qhO0
package com.adt.dao.impl; "3&bh>#qY
UyFvj4SU
import java.util.List; g2Hz[C(
A7`+XqG
import org.flyware.util.page.Page; V(lxkEu/Fj
3^jkd)xw
import net.sf.hibernate.HibernateException; [9<c;&$LU
import net.sf.hibernate.Query; J Wh5gOXd
+#;t.&\80N
import com.adt.dao.UserDAO; Z=[qaJ{]
r$8(Q'
/** V4["+Y
* @author Joa n]3Lqe;
*/ g-C)y
06
public class UserDAOImpl extends BaseDAOHibernateImpl f9%M:cl
!t;B.[U *
implements UserDAO { #<$pl]>}t
+.czj,Sq
/* (non-Javadoc) /8cfdP Ba
* @see com.adt.dao.UserDAO#getUserByName GbXa=*
<-<
rtjUHhF
(java.lang.String) s%bm1$}
*/ k<Y}BvAYB
publicList getUserByName(String name)throws _?}[7K!~d
R!+_mPb=Q*
HibernateException { :@~Nszlb
String querySentence = "FROM user in class YcRo>:I
GLBzlZ?
com.adt.po.User WHERE user.name=:name"; {uCXF~v
Query query = getSession().createQuery |8{c|Qz
ln1QY"g
(querySentence); M?gc&2Y
query.setParameter("name", name); G7qB
return query.list(); pdw;SIoC
} |//D|-2
vkj Hh.
/* (non-Javadoc) (kY wD
* @see com.adt.dao.UserDAO#getUserCount() J<9;Ix8R
*/ ov
'g'1}
publicint getUserCount()throws HibernateException { vY"i^a`f
int count = 0; 'NAC4to;;
String querySentence = "SELECT count(*) FROM \yE*nZ
&6@#W]_
user in class com.adt.po.User"; zObrp
Query query = getSession().createQuery #0*oj/
JS!`eO/8
(querySentence); -"CXBKHb
count = ((Integer)query.iterate().next E,}(jAq7
%a=^T?8
()).intValue(); it.'.aK4
return count; *[|a$W
} =C(((T.
;irAq|
/* (non-Javadoc) ?qmJJ5Gn
* @see com.adt.dao.UserDAO#getUserByPage w(N$$
#xoFcjRE
(org.flyware.util.page.Page) gebDNl\Y2
*/ EyDH-}Y
publicList getUserByPage(Page page)throws +a'["Gjq;
/)J]m
HibernateException { FoX,({*Ko~
String querySentence = "FROM user in class gucgNpX
KsDovy<
com.adt.po.User"; y5/LH~&Ov
Query query = getSession().createQuery Hp(wR'(g&
">M:6\B
(querySentence); &&>Tfzh
query.setFirstResult(page.getBeginIndex()) -)%gMD~z1
.setMaxResults(page.getEveryPage()); x4N*P
return query.list(); =J GL~t?
} @c-| Sl
0F-%C>&g
} EEp~\^-
ra|Ku!
3+WmM4|
dr gCr:Gf
x:E:~h[.^
至此,一个完整的分页程序完成。前台的只需要调用 \LYNrL~?J
(`js/7[`H[
userManager.listUser(page)即可得到一个Page对象和结果集对象 hRI?>an
=,J-D6J?
的综合体,而传入的参数page对象则可以由前台传入,如果用 nr?| !gj
\"|7o8
webwork,甚至可以直接在配置文件中指定。 vUR@P
-
wv.HPmq
下面给出一个webwork调用示例: TMG|"|
java代码: 8D&yFal
SH5a&OVZhn
1~ZFkcV_C
/*Created on 2005-6-17*/ yt{?+|tXU
package com.adt.action.user; )1E#'v12"
Ca}V5O
import java.util.List; l_i&8*=Px
J,D^fVIw
import org.apache.commons.logging.Log; QIC? `hk1
import org.apache.commons.logging.LogFactory; fA"9eUu
import org.flyware.util.page.Page; ^u+#x2$Mg
pC/13|I
import com.adt.bo.Result; aXgngwq
import com.adt.service.UserService; 7U2?in}?Qi
import com.opensymphony.xwork.Action; /_!Ed]
+lhnc{;WJv
/** /2x@Z>
* @author Joa y1bo28
*/ V|vXxWm/
publicclass ListUser implementsAction{ 'j$n;3
V)Ze>Pp
privatestaticfinal Log logger = LogFactory.getLog )W^$7Em
^D?{[LBc
(ListUser.class); 62 9g_P)
(b"kN(
private UserService userService; =3EE-%eF!
?#lHQT
private Page page; xs^wRE_
b6d}<b9#
privateList users; 7qLB 9r
I#:Dk?"O2
/* S#b)RpY
* (non-Javadoc) sf Zb$T
J
* 34I;DUdcE
* @see com.opensymphony.xwork.Action#execute() f/670Acv
*/ UgTgva>?
publicString execute()throwsException{ 9dwLkr
Result result = userService.listUser(page); jk{m8YP)E
page = result.getPage(); C#@-uo2
users = result.getContent(); B)BR
y%
return SUCCESS; |e91KmiqJ
} Ge ?Q)N
+ctJV>
/** w,-4A
o2x
* @return Returns the page. Sr>5V
*/ U"535<mR
public Page getPage(){ ]92=PA>75
return page; >rY^Un{Z
} 3
p!t_y|SX
jJV1 /]TJ
/** V)c.AX5
* @return Returns the users. nq:'jdY5|
*/ KT0Pmpp5
publicList getUsers(){ l{Xy %8
return users; g(l:>=g]?
} T U^s!Tj
P\%aJ'f~
/** ^!Tq(t5V
* @param page -Yg?@yt
* The page to set. =kb/4eRg
*/ ]<k+a-Tt
publicvoid setPage(Page page){ h*V~.H
this.page = page; 4U*CfdZZ
} ) ):w`^6
({mlA`d]
/** NY/-9W5T4
* @param users NBD1k;
* The users to set. p7Z/%~0v:
*/ 5zPn-1uW
publicvoid setUsers(List users){ {Z}zT1kA
this.users = users; <
49\B
} M%2w[<-8c
co*XW
/** j/uzsu+
* @param userService a *qc
* The userService to set. 87rHW@\](
*/ |XJ|vQGU
publicvoid setUserService(UserService userService){ 2XrYm"6w
this.userService = userService; zKQXmyO
} c@lH
} [Uw3.CVh
Mo]
d5'4RYfkQ
!=?Q>mz
}tbZ[:T{K
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, |u.3Tp|3W
QG
1vP.K
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 g2 tM!IRQ
;FnS=Z
么只需要: OE2r2ad
java代码: pE6r7
@;Xa&*
cG!dMab(
<?xml version="1.0"?> %JuT'7VB
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~8Ez K_c
o)M<^b3KO
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Wb;D9Z
=QhK|C!$A
1.0.dtd"> [#2X
5>>JQ2'W
<xwork> s} oD?h:T3
_f@nUv*
<package name="user" extends="webwork- 2Zr,@LC
is`~C
interceptors"> \vgM`32<
[E0.4FLT!
<!-- The default interceptor stack name R0T{9,;[`
fz<GPw
--> ?pV!`vp^{
<default-interceptor-ref yUvn h
0A F}wz>
name="myDefaultWebStack"/> -_irkpdC[
qP72JxT
<action name="listUser" x<=R?4@rq
<X ([VZ
class="com.adt.action.user.ListUser"> z0?IQzR^T
<param zE?@_p1gei
9lB$i2G>Zw
name="page.everyPage">10</param> ;]_h")4"c
<result U4h5K}j4
4E@_Fn_#
name="success">/user/user_list.jsp</result> VVk8z6W
</action> S&NWZ:E3[
newURb,-!
</package> &e99P{\D
!rff/0/x"
</xwork> 40%<E
c. }#.-b8
z7R2viR[
n7L|XkaQ
H4uHCkj
fy={
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 7,FhKTV1/
9/dADJe0b
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 e,T^8_>
qD{~QHDa
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 _ c,{}sn
RAFdo
c1Hp
2!GyQ@&[W
R,m|+[sl
我写的一个用于分页的类,用了泛型了,hoho Ym
1; /'
V:2{LR<R8
java代码: 3y yVI#
&S8,-~U
["15~9
package com.intokr.util; ]r>m{"~E
I.kuYD62
import java.util.List; Cps'l
f'OcW*t
/** K6N+0#
* 用于分页的类<br> 1'b}Y8YO
* 可以用于传递查询的结果也可以用于传送查询的参数<br> WZcAwYB
* S%3&Y3S
* @version 0.01 fiW2m=h_
* @author cheng 6/&|)gW',
*/ )jm!^m
public class Paginator<E> { 1:Wl/9mL
privateint count = 0; // 总记录数 K1zH\wH
privateint p = 1; // 页编号 uIR/^o
privateint num = 20; // 每页的记录数 \ `|
privateList<E> results = null; // 结果 6`Diz_(
QUWx\hqE
/** ;!)gjiapw
* 结果总数 G| qsJ
*/ BB.120v&N
publicint getCount(){ drS>~lSxB
return count; \Yr&vX/[p
} _eUd
RL>
|J:m{
publicvoid setCount(int count){ LKYcE;n
this.count = count; L@`:mK+;
} eJE!\ucS2W
l4\ !J/df
/** {}"a_L&[;
* 本结果所在的页码,从1开始 hQaa"U7[
* /g$8JL
* @return Returns the pageNo. ;nKhmcQ4
*/ +.McC$!s
publicint getP(){ 0Z
jE(3i
return p; H6<3'P
} u^( s0q
Fz2CXC
/** r:H.VAD
* if(p<=0) p=1 (1)b> 6
* yHn8t]{
* @param p qE M,~:lTn
*/ hI,+J>
publicvoid setP(int p){ Vsd4;
if(p <= 0) =h[;'v{
p = 1; ?gG%FzfQ/
this.p = p; $'COsiK7
} )p[Qj58
wQojmmQ
/** (/A
6kp?
* 每页记录数量 ](>YjE0
*/ gQuU_dbXSB
publicint getNum(){ (8Te{K h'
return num; zin'&G>l
} lKV7IoJ&;
g:Fo7*i
/** 5EL&?\e
* if(num<1) num=1 Vw5Pgt x
*/ AA[?a
publicvoid setNum(int num){ M\r=i>(cu
if(num < 1) QG5)mIJ
num = 1; JY$+<`XM
this.num = num; Vs(D(d,
} L[MAc](me-
Wt!8.d}=
/** "B*UZ.cC
* 获得总页数 -*W\$P
*/ '3
JVUHn
publicint getPageNum(){ Iy Vmz'
return(count - 1) / num + 1; lQG;WVqW
} 2tZ\/6G<
g&X
X@I8+v
/** =m
U</ F)
* 获得本页的开始编号,为 (p-1)*num+1 `Wp y6o
*/ wN:vI(C
publicint getStart(){ sq+cF/jo6
return(p - 1) * num + 1; ?6 "B4%7b
} na3lbwq
Ie4Xk
/** bDnT><eH
* @return Returns the results. Wo6C0Z3g}
*/ I|_U|H!`
publicList<E> getResults(){ h&z(;B!;y.
return results; ;Ngu(es6
} L<p.2[3
3q.HZfN~
public void setResults(List<E> results){ Y/qs\c+
this.results = results; \{ff7_mLo
} CykvTV Q
T*](oA@
public String toString(){ 7mnZ,gpb
StringBuilder buff = new StringBuilder #ib?6=sPC
cCq mrjUmV
(); As(6E}{S
buff.append("{"); G<`6S5J>hr
buff.append("count:").append(count); }a!c
buff.append(",p:").append(p); 8jz7t:0
buff.append(",nump:").append(num); /<CgSW}
buff.append(",results:").append lLN5***47J
[y(<1]i-a
(results); T)MZ`dM
buff.append("}"); ab>>W!r@!
return buff.toString(); LNF|mS\+D
} {emym$we
x,#?
} -S
0dr8E
z W*Z
,b74m