Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 SqQB>;/p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 nm.d.A/]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 hW&UG#PY>
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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 !NtY4O/
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分页支持类: =\.|'
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java代码: :h@:F7N _
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package com.javaeye.common.util; ~r3g~MCHS
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import java.util.List; EQ -\tWY
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publicclass PaginationSupport { l(W3|W#P
^8)d8?}
publicfinalstaticint PAGESIZE = 30; ;f\0GsA#
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privateint pageSize = PAGESIZE; ewY X \
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privateList items; vbp)/I-h
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privateint totalCount; \=JKeL|6[S
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privateint[] indexes = newint[0]; 3h&s=e!
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privateint startIndex = 0; NbdaP{{
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public PaginationSupport(List items, int Jx]`!dP3
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totalCount){ ;FUd.vg{
setPageSize(PAGESIZE); R0>L[1o
setTotalCount(totalCount); uB
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setItems(items); WG,{:|!E
setStartIndex(0); <Ip}uy[Y
} @4pN4v8U
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public PaginationSupport(List items, int YG_3@`-<
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totalCount, int startIndex){ H5n"!!
setPageSize(PAGESIZE); Kxq~,g=t
setTotalCount(totalCount); ;]gph)2cd
setItems(items); +J2=\YO
setStartIndex(startIndex); VH/_0
} lH[N*9G(
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public PaginationSupport(List items, int F
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totalCount, int pageSize, int startIndex){ : v]< h
setPageSize(pageSize); E4PP&'
setTotalCount(totalCount); ?@ O[$9y
setItems(items); \(Iy>L.
setStartIndex(startIndex); KF.?b]
} v^vEaB
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publicList getItems(){ (g 8K?Q
return items; `O[M#y%*E
} R
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publicvoid setItems(List items){ PpbW+}aCF
this.items = items; :Z<-J`
} `.n[G~*w~1
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publicint getPageSize(){ rVkHo*Q
return pageSize; lGxG$0`;;
} Ji=E 1R
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publicvoid setPageSize(int pageSize){ U!('`TYe
this.pageSize = pageSize; mFT[[Z#
} `jP6;i
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publicint getTotalCount(){ ~(}zp<e|
return totalCount; Zf|f $1-
} (HY|0Bgr
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publicvoid setTotalCount(int totalCount){ !x>P]j7A}Y
if(totalCount > 0){ +&|WC2#
this.totalCount = totalCount; zF{5!b
int count = totalCount / &DgIykqN
REw!@Y."
pageSize; pCv=rK@
if(totalCount % pageSize > 0) <MY_{o8d
count++; x}-r Ar
indexes = newint[count]; #[IQmU23
for(int i = 0; i < count; i++){ zc(-dMlK
indexes = pageSize * ?!Y2fK=h0
N~SG=\rP;o
i; # *\PU
} dq[CT
}else{ VaH#~!
this.totalCount = 0; Fe:0nr9;
} ,rQznE1e
} 9hcZbM]
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publicint[] getIndexes(){ "Y4tt0I
return indexes; (G:$/fK
} o <sX6a9e
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publicvoid setIndexes(int[] indexes){ Kx ';mgG#$
this.indexes = indexes; |FH/Q-7[
} [&6l=a
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publicint getStartIndex(){ 74QWGw`,
return startIndex; ]ZZ7j
} JTrxh]
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publicvoid setStartIndex(int startIndex){ 4u A;--j
if(totalCount <= 0) ?mnwD ]u
this.startIndex = 0; eo"6 \3z
elseif(startIndex >= totalCount) .hnGHX
this.startIndex = indexes 8\/E/o3
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[indexes.length - 1]; BT>8
elseif(startIndex < 0) $f_Brc:n {
this.startIndex = 0; ACc.&,!IZ
else{ >AV?g8B;
this.startIndex = indexes anHP5gD
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[startIndex / pageSize]; t/pHdxX*C7
} ;DBO
} {}[S,L
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publicint getNextIndex(){ KR#Bj?fz-H
int nextIndex = getStartIndex() + DtR-NzjB
uG~%/7Qt{
pageSize; 'Q?nU^:F#
if(nextIndex >= totalCount) IKH#[jW'IB
return getStartIndex(); 5Tkh6 s
else =]E;wWC
return nextIndex; qVx0VR1:
} 8g^OXZ
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publicint getPreviousIndex(){ (WX,&`a<$
int previousIndex = getStartIndex() - dyD=R
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pageSize; Y<I/y
if(previousIndex < 0) t
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return0; hBOI:4u[
else &K|<7Efx
return previousIndex; '
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} o0_RU<bWN
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} rU%\ 8T0f
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抽象业务类 32:q'
java代码: 8it|yK.G@&
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/** [_#9PH33
* Created on 2005-7-12 O\-cLI<h2
*/ 48Z{wV,
package com.javaeye.common.business; W1i Kn
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import java.io.Serializable; <$K%u?
import java.util.List; fOF02WP^
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import org.hibernate.Criteria; <{JHFU`^
import org.hibernate.HibernateException; A !x"*
import org.hibernate.Session; 8J7xs6@
import org.hibernate.criterion.DetachedCriteria; ]@)X3}"!
import org.hibernate.criterion.Projections; z
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import @_YlHe&W
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org.springframework.orm.hibernate3.HibernateCallback; Zm4IN3FGLv
import ?S36)oZzg
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org.springframework.orm.hibernate3.support.HibernateDaoS bBb$0HOF
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upport; uL1e?
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import com.javaeye.common.util.PaginationSupport; 1}}.e^Tsfr
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public abstract class AbstractManager extends GTyS8`5E*
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HibernateDaoSupport { mpIRe@#Z
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privateboolean cacheQueries = false; ~6Vs>E4G
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privateString queryCacheRegion; g>CF|Wj
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publicvoid setCacheQueries(boolean TwqyQ49
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cacheQueries){ &gw. &/t
this.cacheQueries = cacheQueries; *1$rg?yGf
} )0
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publicvoid setQueryCacheRegion(String BOQ2;@:3
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queryCacheRegion){ VrD?[&2pE
this.queryCacheRegion = ;$wS<zp6
) ^'Q@W
queryCacheRegion; !;x
} fILINW{Yk)
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publicvoid save(finalObject entity){ s7A{<>:
getHibernateTemplate().save(entity); k"uqso/
} C7dy{:y`
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publicvoid persist(finalObject entity){ h/?8F^C#v
getHibernateTemplate().save(entity); rp6Y&3p.
}
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publicvoid update(finalObject entity){ vRpMZ)e
getHibernateTemplate().update(entity); vQ#$.*Cvn
} 4_ztIrw
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publicvoid delete(finalObject entity){ q.yS j
getHibernateTemplate().delete(entity); O[+S/6uy
} :bkACuaEn
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publicObject load(finalClass entity, FVW<F(g`
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finalSerializable id){ 8 P.t
return getHibernateTemplate().load 17I{_C
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(entity, id); #UG| \}Lp
} ZSuUmCm
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publicObject get(finalClass entity, :DXkAb2
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finalSerializable id){ O8(;=exA
return getHibernateTemplate().get I\&..e0l
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(entity, id); PspH[db
} zmQ V6o=k
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publicList findAll(finalClass entity){ IHZ WNT2
return getHibernateTemplate().find("from 7Vr .&`l
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" + entity.getName()); M=HW2xn
} " ^u
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publicList findByNamedQuery(finalString ?7 e|gpQ|
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namedQuery){ uc<XdFcu
return getHibernateTemplate VT96ph
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().findByNamedQuery(namedQuery); QU|{(c
}
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publicList findByNamedQuery(finalString query, :~3sW< PR
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finalObject parameter){ \:mx Ri
return getHibernateTemplate */sVuD^b`
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().findByNamedQuery(query, parameter); %H75u6
} B(wk $2
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publicList findByNamedQuery(finalString query, #Z;ziM:
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finalObject[] parameters){ -sm{Hpf_b
return getHibernateTemplate $9Hod-Z1
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().findByNamedQuery(query, parameters); 9:4PJ%R9
} `e .;P
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publicList find(finalString query){ s
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return getHibernateTemplate().find 2hdi)C,7Y
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(query); M,"4r^%k
} 9a 9<I
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publicList find(finalString query, finalObject '31pb9@fH
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parameter){ z)xGZ*{=
return getHibernateTemplate().find H$au02dpU
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(query, parameter); Idop!b5!
} A(X~pP&oF
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public PaginationSupport findPageByCriteria hV#+joT8i
<Z{\3X^
(final DetachedCriteria detachedCriteria){ ]IMBRZQqb
return findPageByCriteria fqZqPcT0
hAi50q;z
(detachedCriteria, PaginationSupport.PAGESIZE, 0); )[yM4QFl
} u6IEBYG ((
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public PaginationSupport findPageByCriteria Iz,a
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(final DetachedCriteria detachedCriteria, finalint zD}dvI}
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startIndex){ CT+pkNC
return findPageByCriteria jJdw\`
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(detachedCriteria, PaginationSupport.PAGESIZE, a97A{7I&
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startIndex);
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} VFz(U)._
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public PaginationSupport findPageByCriteria z #c)Q
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(final DetachedCriteria detachedCriteria, finalint TzmoyY
= q9>~E{}
pageSize, LL|$M;S
finalint startIndex){ mG@xehH
return(PaginationSupport) W=41jw
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getHibernateTemplate().execute(new HibernateCallback(){ /*!K4)$-*2
publicObject doInHibernate w^e<p~i!^E
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(Session session)throws HibernateException { ^d Fdw\
Criteria criteria = [U@#whE O
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detachedCriteria.getExecutableCriteria(session); 5VdF^.:u
int totalCount = }eb}oK
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((Integer) criteria.setProjection(Projections.rowCount &dp<i[ec^
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()).uniqueResult()).intValue(); u!?cKZw
criteria.setProjection 5xX*68]%
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(null); $50A!h
List items = e}Cp;c]=
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criteria.setFirstResult(startIndex).setMaxResults <gRv7 ?V[z
ysm)B?+k
(pageSize).list(); }/q]:3M|
PaginationSupport ps = ~c~N _b
*>,8+S33r{
new PaginationSupport(items, totalCount, pageSize, .)~IoIW=
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startIndex); H4p N+
return ps; !]=[h
} FB-?{78~
}, true); 4^\5]d!
} u^T)4~(
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public List findAllByCriteria(final bzD <6Z
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DetachedCriteria detachedCriteria){ DjUif "v
return(List) getHibernateTemplate oe`t ? (U
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().execute(new HibernateCallback(){ k44sV.G4L
publicObject doInHibernate L;$Gn"7~
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(Session session)throws HibernateException { T {Q]
Criteria criteria = ,pL%,>R5
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detachedCriteria.getExecutableCriteria(session); It>8XKS
return criteria.list(); F33&A<(,
} ={ P
}, true); 78&(>8@m
} a<-NB9o~v
"
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public int getCountByCriteria(final 7qj<|US
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DetachedCriteria detachedCriteria){ cnJ(Fv_F$
Integer count = (Integer) %~Vgz(/
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getHibernateTemplate().execute(new HibernateCallback(){ +EG?8L,z
publicObject doInHibernate [)UL}vAO\q
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(Session session)throws HibernateException { 6S7 =+>
Criteria criteria = T pXbJ]o9
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detachedCriteria.getExecutableCriteria(session); L:UJur%
return j6<o,0P
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criteria.setProjection(Projections.rowCount 'jh9n7mH
[~e{58}J|
()).uniqueResult(); WgX9k J
} 6$]@}O^V
}, true); W2cgxT
return count.intValue(); ?/"Fwjau
} ,SQmQ6h
} _"Yi>.{]
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用户在web层构造查询条件detachedCriteria,和可选的 %6Wv-:LY
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 j"g[qF/*
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PaginationSupport的实例ps。 O#Y;s;)i"
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ps.getItems()得到已分页好的结果集 17IT:T,'
ps.getIndexes()得到分页索引的数组 esE5#Yq4.k
ps.getTotalCount()得到总结果数 2}:{}pw
ps.getStartIndex()当前分页索引 XIQfgrGZ
ps.getNextIndex()下一页索引 BPRhGG|9j
ps.getPreviousIndex()上一页索引 *$+k-BV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 qz]b8rX
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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 AcC'hr.N+
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一下代码重构了。 d@-s_gw
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我把原本我的做法也提供出来供大家讨论吧: um.s:vj$
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首先,为了实现分页查询,我封装了一个Page类: /;P* ?
java代码: Y\#+-E
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/*Created on 2005-4-14*/ n`'v8 `a]
package org.flyware.util.page; WGy3SV )
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/** 08*O|Ym,
* @author Joa \~j6}4XS1.
* B?o ?LI
*/ ~\4`tc
publicclass Page { kC :pal
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/** imply if the page has previous page */ P!uwhha/g
privateboolean hasPrePage; H# P)n
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/** imply if the page has next page */ ]<y _
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privateboolean hasNextPage; g$=y#<2?
*c"tW8uR
/** the number of every page */ 1E3'H7k\t
privateint everyPage; snU
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&
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/** the total page number */ Y"eR&d
privateint totalPage; d:|(l^]{r
V*
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^
/** the number of current page */ DdAs]e|D[
privateint currentPage; gZ{q85C.>
UD.&p'^ /{
/** the begin index of the records by the current wO\,?SI4
s+mNr3
query */ t?bc$,S"\(
privateint beginIndex; y~ubH{O#
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/** The default constructor */ <qGVOAnz+
public Page(){ Z]Zs"$q@
mv%Zh1khn/
} funHznRR
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/** construct the page by everyPage gW0{s[}T
* @param everyPage ZH
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* */ (<.uvq61
public Page(int everyPage){ {u7%Z}<0
this.everyPage = everyPage; 8vP:yh@
} a04I.5!
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/** The whole constructor */ ?U}Ml]0~
public Page(boolean hasPrePage, boolean hasNextPage, bKAR}JM&
6x6xv:\
c UJUZ@ol
int everyPage, int totalPage, Z:TW{:lrI
int currentPage, int beginIndex){ X?3?R\/
this.hasPrePage = hasPrePage; IiX`l6L~W
this.hasNextPage = hasNextPage; ^
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this.everyPage = everyPage; WziX1%0$n
this.totalPage = totalPage; l~cT]Ep
this.currentPage = currentPage; %Fb4
this.beginIndex = beginIndex; kaKV{;UM
} [ij8h,[~]
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/** D7'P^*4_B
* @return *ud"?{)Z
* Returns the beginIndex. lQt&K1m
*/ jg,oGtRz
publicint getBeginIndex(){ vbol70
return beginIndex; ,[ogh
} Y(:.f-Du
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/** 47(/K2
* @param beginIndex hvc%6A\nm
* The beginIndex to set. \I3={ii0
*/ ]7#@lL;'0
publicvoid setBeginIndex(int beginIndex){ \QpH~&QIS
this.beginIndex = beginIndex; iJIDx9 )Z
} d{~5tv- H
=CCxY7)M+.
/** ue YBD]3'
* @return >'qkW$-95
* Returns the currentPage. MV+S.`R
*/ zAr@vBfC%
publicint getCurrentPage(){ !a(#G7zA
return currentPage; wK0= I\WN9
} dcK7Dd->
#<^ngoOj
/** 8ec6J*b
* @param currentPage 8Gw0;Uu8D
* The currentPage to set. jjs1Vj1@<
*/ 4sj:%%UE
publicvoid setCurrentPage(int currentPage){ ^CZ)!3qd1
this.currentPage = currentPage; =f4v: j}'|
} q;XO1Se
z j[/~I
/** kX\\t.nH
* @return $U{\T4
* Returns the everyPage.
]+ \]2`?
*/ ?2;gmZd7
publicint getEveryPage(){ i]qVT)j
return everyPage; upD2vtU
} ;k<n}shD
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/** <G5d{rKZ
* @param everyPage . q=sC?D
* The everyPage to set. /1h
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*/ !jV}sp<Xp
publicvoid setEveryPage(int everyPage){ 09_L^'`
this.everyPage = everyPage; |'C{nTX
} 6?"k&O
Q t!X<.
/** ev bqBb21b
* @return wEMh !jAbv
* Returns the hasNextPage. $#bgt
*/ #U46Au
publicboolean getHasNextPage(){ FIB 9W@oao
return hasNextPage;
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} \~3g*V
G! y~Y]e
/** kQr\ktN\
* @param hasNextPage K):MT[/"
* The hasNextPage to set. L_3undy,
*/ #0i] g)
publicvoid setHasNextPage(boolean hasNextPage){ ~@3X&E0S
this.hasNextPage = hasNextPage; h{&X`$
} c<'Pt4LY
Z+zx*(X
/** >bKN$,Qen
* @return b~M3j&
* Returns the hasPrePage. **zh>Y}6
*/ (c{<JYEC
publicboolean getHasPrePage(){ %E!^SF?Y
return hasPrePage; tkN5|95
} {}vB#!
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/** w(sD}YA)
* @param hasPrePage L5E|1T
* The hasPrePage to set. 1T{A(<:o$
*/ LI>tN R~
publicvoid setHasPrePage(boolean hasPrePage){ ~S\Ee 2e>
this.hasPrePage = hasPrePage; *?k~n9n5U
} uC_&?
oGK 1D
/** Cst:5m0!
* @return Returns the totalPage. S 1%/ee3
* pa7Iz^i
*/ RJ#xq#l
publicint getTotalPage(){
\= M*x
return totalPage; +) pO82
} )czuJ5
s^
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/** p4\r`
* @param totalPage Z#-:zD7_
* The totalPage to set. DI P(
*/ XJ3 5Z+M
publicvoid setTotalPage(int totalPage){ _L?`C
this.totalPage = totalPage; i7qG5U
} mN_KAln
:{iS0qJ
} t%<@k)hd~G
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(
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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 3Mvm'T:[
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个PageUtil,负责对Page对象进行构造: hFDY2Cp]D
java代码: MroJ!.9
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/*Created on 2005-4-14*/ ~^U(G As
package org.flyware.util.page; D ^ mfWJS
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import org.apache.commons.logging.Log; w7.I0)MH
import org.apache.commons.logging.LogFactory; -t92! O
v&[Ff|>
/** 9=(*#gRd
* @author Joa J|DID+M
* 3y}0J @
*/ #d+bld \
publicclass PageUtil { "=7y6bM
xLfx/&2
privatestaticfinal Log logger = LogFactory.getLog n'<FH<x
vT*z3
(PageUtil.class); R %QgOz3`
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/** l]BIFZ~
* Use the origin page to create a new page ]!yuD/4A
* @param page 6
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* @param totalRecords aP}kl[W
* @return D^(Nijl9U
*/ W'Wr8~{h
publicstatic Page createPage(Page page, int 5*.JXxE;U
JLS|G?#0
totalRecords){ gr\UI!]F
return createPage(page.getEveryPage(), .OLm{
ar-N4+!@
page.getCurrentPage(), totalRecords); %3L4&W_T
} %P!6cyQS
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/** KrcL*j&^
* the basic page utils not including exception +{Qk9Z
W^}fAcQKH
handler aCu 8
D!
* @param everyPage \2q!2XWgK
* @param currentPage 6,nws5dh
* @param totalRecords {rQSB;3
* @return page ]>E)0<t
*/ y be:u
publicstatic Page createPage(int everyPage, int B}Q.Is5
f(Vr &X
currentPage, int totalRecords){ Hw 7
everyPage = getEveryPage(everyPage); |@{4zoP_N
currentPage = getCurrentPage(currentPage); idWYpU>gC
int beginIndex = getBeginIndex(everyPage, rJ2yi6TB\
D%L}vugxK
currentPage); *v+xKy#M
int totalPage = getTotalPage(everyPage, lTl-<E;
tI2V)i!
totalRecords); 7 &y'\
boolean hasNextPage = hasNextPage(currentPage, D6cqON0a.
3lw
KV
totalPage); (;RmfE'PX
boolean hasPrePage = hasPrePage(currentPage); \-XQo
1SddZ5
returnnew Page(hasPrePage, hasNextPage, c{YBCWA
everyPage, totalPage, aRPpDSR?l
currentPage, W(^R-&av
FsZW,
beginIndex); #G'Y2l
} qmNg Ez%
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privatestaticint getEveryPage(int everyPage){ oD_n+95B
return everyPage == 0 ? 10 : everyPage; T$ <l<.Qd
} q J)[2:.G
ELh`|X
privatestaticint getCurrentPage(int currentPage){ PL;PId<9w
return currentPage == 0 ? 1 : currentPage; XH9Y|FX%#
} :bJT2o[
;?-A4!V,
privatestaticint getBeginIndex(int everyPage, int QWqEe|}6
Q8]lz}
currentPage){ $)UMRG
return(currentPage - 1) * everyPage; /oA=6N#j
} mmE!!J`B
DG2CpR)S
privatestaticint getTotalPage(int everyPage, int L>4!@L5)
tOQ2947zk
totalRecords){ dMo456L
int totalPage = 0; A .]o&S}
: ,0F_["3
if(totalRecords % everyPage == 0) {s ]yP_
totalPage = totalRecords / everyPage; }/dGC;p"
else K9{]v=#I
totalPage = totalRecords / everyPage + 1 ; fk*$}f
!bf8
r
return totalPage; qa>Z?/w
} Dt)O60X3>
HF(pC7/a:
privatestaticboolean hasPrePage(int currentPage){ qnFi./
return currentPage == 1 ? false : true; 7x6q:4Ep\
} $~$NQe!/
]/G~ L
privatestaticboolean hasNextPage(int currentPage, x~!gGfP
nT(Lh/
int totalPage){ =6PTT$,
return currentPage == totalPage || totalPage == _J|cJ %F>%
{KH!PAh
0 ? false : true; ^oykimYI-
} yeI((2L@E2
Qn=#KS8=J
eSAB :L,K
} A6ar@$MZ
!CJh6X!
B,2oA]W"S
\FE
$ mH'%YDIl
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。 E5>y?N
],!7S"{97
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 w;e42.\
^p@R!228
做法如下:
vvWje:H
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x{GKz#
l"T{!Oq
的信息,和一个结果集List: OI@;ffHSW
java代码: "pa}']7#
A.f!SYV6
S,I|8
YE
/*Created on 2005-6-13*/ w+^z{3>
package com.adt.bo; @ V_@r@A
;v}f7v '
import java.util.List; WTlR>|Zdn
**RW
9FU
import org.flyware.util.page.Page; bcVzl]9
#$W bYL|
/** \Z?.Po`!j
* @author Joa at N%csA0
*/ #b^x! lR
publicclass Result { e!eUgD
d]fo>[%Xr
private Page page; ")gd)_FOS
GjHV|)^
private List content; ap
5D6y+
.}xF2'~E/
/** E%+ aqA)f
* The default constructor oU\Q|mN(
*/ y2_^lW%
public Result(){ (]Zyk,[
super(); do-mkvk
} oB BL7/L
f@G3,u!]i
/** <'Ppu
* The constructor using fields :J
7p=sX
* ?PpGBm2f*
* @param page Kuj*U'ed7t
* @param content 7 3 Oo;
*/ CrTGC%w{=
public Result(Page page, List content){ 1u%e7
this.page = page; TB oN8cB}
this.content = content; ~|FKl%
} K3CTxU(
*5Mg^}ZC5
/** J)148/
* @return Returns the content. Ke5fe#
*/ ?;q
publicList getContent(){ Y{Yp N
return content; uU|fCwQt
} Z'u:Em
)P)Zds@F
/** | e&v;48
* @return Returns the page. =Wgz\uGJ
*/ 31FQ=(K
public Page getPage(){ .q!U@}k.
return page; AV t(e6H
} `S&$y4|Vs
|Z"5zL10
/** r@|{m QOxa
* @param content CO)BF%?B
* The content to set. L\`uD[g
*/ XBTtfl
&
public void setContent(List content){ {H\(H_X
this.content = content; >$%rs c}^
} 9rd7l6$R"
i&%/]Nq
/** 6wmMg i_m
* @param page tB,1+I=
* The page to set. )|d]0/<
*/ )q+Qtz6D
publicvoid setPage(Page page){ n)~9
this.page = page; \Y?ByY
} G"xa"hGF
} EYLqg`2A
6)@Y 41H]C
8M"0o}wx
>f !
-0tHc=\u(
2. 编写业务逻辑接口,并实现它(UserManager, b }^ylm
*8a8Ng
UserManagerImpl) H*h 7Y*([
java代码: bPe|/wp
jRhOo%p
cyQ&w>'
/*Created on 2005-7-15*/ 52zD!(
package com.adt.service; nw)yK%`;M
U}=o3u
import net.sf.hibernate.HibernateException; M^e;WY@ D
+H'{!:e5
import org.flyware.util.page.Page; $_u9Y!
7*a']W{aJ
import com.adt.bo.Result; i6.HR?n
9"jhS0M
/** Kt 0
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* @author Joa gbl`_t/
*/ }8zw| (GR,
publicinterface UserManager { sfN6ro
V>Zw" #Q
public Result listUser(Page page)throws 7Zf
*T
4dd] Ju
HibernateException; t:SME'~.P
&'0|U{|
} d/m.VnW
IwR/4LYI
?xb4y=P7
'5*8'.4Sy
!^,<nP
java代码: hm&cRehU
]<zjD%Ez
@5C!`:f
/*Created on 2005-7-15*/ k3w(KH@
package com.adt.service.impl; 5 wT
e?
.5'_5>tkv
import java.util.List; 2<
"-
&* Aems{-
import net.sf.hibernate.HibernateException; :'F7^N3;H
Q#Vg5H4
import org.flyware.util.page.Page; V"r2 t9A
import org.flyware.util.page.PageUtil;
OH*
(PM!{u=
import com.adt.bo.Result; MoFAQe
import com.adt.dao.UserDAO; tr<iFT}C
import com.adt.exception.ObjectNotFoundException; XITh_S4fs=
import com.adt.service.UserManager; 'on8r*
;:%*h2
/** zFq8xw
* @author Joa c^?+"7oO0
*/ B9&$sTAB
publicclass UserManagerImpl implements UserManager { q0>@!1Wb
+W8L^Wl
private UserDAO userDAO; 74c[m}'S
Cd"cU~HAB
/** 6^'BhHP
* @param userDAO The userDAO to set. &azy1.i~
*/ &`9p.
publicvoid setUserDAO(UserDAO userDAO){ lo!.%PP|
this.userDAO = userDAO; 9CxFj)#5F
} X}W4dpU,
*Bse3%-v
/* (non-Javadoc) }1sFddGVt
* @see com.adt.service.UserManager#listUser '&OJ hLE
rZK;=\Ot
(org.flyware.util.page.Page) 4|]0%H~n6
*/ t@Bl3Nt{
public Result listUser(Page page)throws ZliJc7lss
`L=d72:
HibernateException, ObjectNotFoundException { [@PD[-2QG3
int totalRecords = userDAO.getUserCount(); >,&@j,?']
if(totalRecords == 0) o-f;$]yp>
throw new ObjectNotFoundException ;4!,19AT
|k:ecw
("userNotExist"); bRhc8#kw)
page = PageUtil.createPage(page, totalRecords); REj<2Lo
List users = userDAO.getUserByPage(page); MKr)6PG,
returnnew Result(page, users); 0[O ."9
} b":3J)Y6.
6N<v&7cSB
} 2j UEL=+Y
*MG*]\D
5r-OE-U{
.:nV^+)
C~r(*nr
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 A.%MrgOOX
TGxmc37?
询,接下来编写UserDAO的代码: ,*r}23
3. UserDAO 和 UserDAOImpl: z87_/(nu
java代码: u5 1%~
`/4R$E{
DA(ur'D
/*Created on 2005-7-15*/ / p PSo
package com.adt.dao; TJhzyJ"t
xaSg'8-
import java.util.List; A'=,q
h,(f3Ik0O
import org.flyware.util.page.Page; ^s;xLGl]
YWXY4*G
import net.sf.hibernate.HibernateException; AB1.l
hR
*\M$pUS{
/** Ul`~d
!3zH
* @author Joa Q~y) V
*/ K4[XP]\jr
publicinterface UserDAO extends BaseDAO { ;GjZvo
: =J^ "c
publicList getUserByName(String name)throws D J:N
el"XD"*
HibernateException; Hx|<NS0}_
'20S oVp
publicint getUserCount()throws HibernateException; F70_N($i
l)m]<EX
publicList getUserByPage(Page page)throws $OAak
0Gr ^#`
HibernateException; "{lw;AA5F
VOY#Y*)g
} (=/%_jj
}R\9ybv
O5lP92],
*Bj7\8cKC
nB+UxU@
java代码: p#
4@
'/[9Xwh9
9wB}EDZ
/*Created on 2005-7-15*/ uHNh|ew21
package com.adt.dao.impl; [Up0<`Q{I_
Z6F^p8O-
import java.util.List; D rMG{Yiu
}iZ>Gm'5
import org.flyware.util.page.Page; R'Y=-
yF
2GB+st,
import net.sf.hibernate.HibernateException; Vo; B#lK
import net.sf.hibernate.Query; p`CVq `k
B/n/bi8T
import com.adt.dao.UserDAO; P\3$Y-id
9_07?`Jr
/** CB1AL]|3
* @author Joa jr=>L:
*/ (oiF05n
h
public class UserDAOImpl extends BaseDAOHibernateImpl i=ztWKwKf
t]QGyW A]
implements UserDAO { K~MTbdg
F-g7*
/* (non-Javadoc) - 2`D(xC
* @see com.adt.dao.UserDAO#getUserByName '(4#He?Gd
D{J+}*y
(java.lang.String) v)VhR2d3
*/ </%n:<z4
publicList getUserByName(String name)throws !K~L&.\T
`H7V['
HibernateException { |K jy4.2
String querySentence = "FROM user in class 2^TJ_xG~
M10u?
com.adt.po.User WHERE user.name=:name"; 0nDlqy6b1b
Query query = getSession().createQuery JOA_2qa>\
Bp.z6x4
(querySentence); QSNLo_z
query.setParameter("name", name); F:P&hK
return query.list(); ndY1j5
} *a2y
Z#i5=,Bk
/* (non-Javadoc) ! 54(K6a[
* @see com.adt.dao.UserDAO#getUserCount() ,M)NC%0X
*/ "V>7u{T
publicint getUserCount()throws HibernateException { #;#r4sJwU
int count = 0; L+b"d3!G&%
String querySentence = "SELECT count(*) FROM OGC|elSM
(ru9Ke%Dx
user in class com.adt.po.User"; ?Ww\D8yV&
Query query = getSession().createQuery qU/,&C
sY#iGEf
(querySentence); :M%s:,]R
count = ((Integer)query.iterate().next hny):59f
lZq`,E_L
()).intValue(); >h+G$&8[y
return count; @6~OQN
} T5jZd@VT,
+EnJyli
/* (non-Javadoc) ,XZ[L?
>
* @see com.adt.dao.UserDAO#getUserByPage o (OC3
| gou#zi
(org.flyware.util.page.Page) 7T)J{:+0!|
*/ pKM5<1J
publicList getUserByPage(Page page)throws w,CZ*/^
g3i !>
HibernateException { luEP5l2&
String querySentence = "FROM user in class jgb>:]:
;h
}^f-
com.adt.po.User"; dF-d
Query query = getSession().createQuery wW1E
'Vy{
e+ZC<Bdh
(querySentence); -bq\2Yc$]
query.setFirstResult(page.getBeginIndex()) ke(LjRS
.setMaxResults(page.getEveryPage()); wJ|wAS
return query.list(); 0k];%HV|
} I2b\[d
e?&4;
} l*l(QvN_
[P*w$Hn
h2Pvj37
bN#)F
I'_.U]An
至此,一个完整的分页程序完成。前台的只需要调用 cX64 X
Ux2pqPb
userManager.listUser(page)即可得到一个Page对象和结果集对象 gda3{g7<)
u/@dWeY[]
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~IB~>5U!
(aO+7ykRuJ
webwork,甚至可以直接在配置文件中指定。 .-:R mYGR
`GG PkTN
下面给出一个webwork调用示例: S"Q$ Ol"
java代码: oXR%A7
o,fBOPIN
^c9~~m16+
/*Created on 2005-6-17*/ 8-HMKD#V
package com.adt.action.user; k($N_XlE
TT(dCHft
import java.util.List; "~f=7
'WUevPmt
import org.apache.commons.logging.Log; @nJ#kd[
import org.apache.commons.logging.LogFactory; e3L<;MAt
import org.flyware.util.page.Page; _~M*XJ] `
olC@nQ1c*
import com.adt.bo.Result; >D';i\2j&
import com.adt.service.UserService; #nL&x3
import com.opensymphony.xwork.Action; wHQyMq^
|7jUf$Q\p
/** ZW}0{8Dk
* @author Joa Vm1U00lM{
*/ 4g.y$
publicclass ListUser implementsAction{ :EK.&%2
LWb5C{
privatestaticfinal Log logger = LogFactory.getLog T/^ /U6JB
#_tixg
(ListUser.class); 2<aBUGA
]hBp
elKJ
private UserService userService; nnU
&R
B=:7N;BT
private Page page; cD6$C31Y]
@x>J-Owd]J
privateList users; a9ab>2G?FR
i%+p\eeq*
/* y@|gG&f
T
* (non-Javadoc) NhxTSyT"t
* H\f.a R=
* @see com.opensymphony.xwork.Action#execute() =NH
p%|
*/ 0ih=<@1 K
publicString execute()throwsException{ o)P'H"Ki
Result result = userService.listUser(page); Y9TaU]7]
page = result.getPage(); [T;0vv8
users = result.getContent(); e+z_Rj%Y;I
return SUCCESS; G<C[A
} 4Lx#5}P
`N~;X~XFk
/** npH2&6Yhi^
* @return Returns the page. uvK1gJrA)
*/ f$x\~y<[
public Page getPage(){ zR'lQ<u
return page; ,y[wS5li
} +8FlDiP
4VjP:>*p
/** g4WN+y`
* @return Returns the users. ZB'/DO=i
*/ .`84Y
publicList getUsers(){ \:
H&.VQ"
return users; "CdL?(
} _5vAnt*
We#u-#k_O
/** [N}:Di,S
* @param page yWa-iHWC
* The page to set. y!SElKj
*/ igp[cFN
publicvoid setPage(Page page){ 'aQ"&GX@
this.page = page; -X ~VXeg
} I3QK~ V*j)
T`f6`1x
/** nV-A0"z_&
* @param users MfhJb_q`
* The users to set. LYPjdp2>"o
*/ W'2|hP
publicvoid setUsers(List users){ {I|iUfy
this.users = users; hL#5:~(
} XV+s 5C
'~{^c}
/** GZ#6}/;b
* @param userService gaaW:* *y
* The userService to set. $srb!&~_>
*/ LB_ylfg
publicvoid setUserService(UserService userService){ k&4@$;Ap
this.userService = userService; 3jIi$X06
} =dD<[Iz6
} i DV.L
%D|27gh
\}Jy=[
bv`gjR
jN:!V t
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Ycypd\q/
7@u0;5p|
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 =(ts~^
OPR+K ?
么只需要: .%7#o
java代码: )cnB>Qul
5|!x0H;
|;o#-YosP
<?xml version="1.0"?> rxu
6 #v F
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >s}bq#x
a;J{'PHu
1.0//EN" "http://www.opensymphony.com/xwork/xwork- F gM<2$h
_D:#M
1.0.dtd"> Z-`j)3Y
JnCp'`
<xwork> 0[@9f1Nk4
c#M'Mye
<package name="user" extends="webwork- (.,`<rXw
ps1ndGp~#
interceptors"> B5>h@p-UV
beFVjVVHq
<!-- The default interceptor stack name rr fL[
U7d%*g
--> |e@9YDZ
<default-interceptor-ref @O#4duM4Qz
CZ*c["x2
name="myDefaultWebStack"/> :1"{0gm
h%
BA,C
<action name="listUser" ;hi+.ng_
#/zPAcV:
class="com.adt.action.user.ListUser"> hc}dS$=C
<param vh3Xd\N
7q*L-Xe]k
name="page.everyPage">10</param> f>i6f@
<result S8mqz.
/Fej)WQp
name="success">/user/user_list.jsp</result> @EH:4~
</action> @^oOXc,r$
^~Nz8PCY
</package> Z,/BPK<e
u1a5Vtel
</xwork> rMIr&T
n.]K"$230
2'_xg~
Mi&,64<
=s`\W7/;{-
1UX"iOx(
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值
z"8%W?o>
WmTSxneo
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 rD)yEuYX
Dk4Jg++
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 +HNY!fv9
XYIZ^_My
pOQ'k>!
sJ)XoK syW
''S*B|:
我写的一个用于分页的类,用了泛型了,hoho Z- ;<R$
<@xp. Y
java代码: ;}{xpJ/
vR<Y1<j
I`kaAOe
package com.intokr.util; BsiHVr
pASNiH698
import java.util.List; VH7VJ [
#y13(u,dN
/** #4"(M9kf
* 用于分页的类<br> $6w[h7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !qPVC\l
* YlDui8.N
* @version 0.01 P]:r'^Yn
* @author cheng 44 ,:@
*/ mxsmW
public class Paginator<E> { +c5z-X$^]
privateint count = 0; // 总记录数 <wUDcF
privateint p = 1; // 页编号 }N^.4HOS8
privateint num = 20; // 每页的记录数 l<qK'
P4
privateList<E> results = null; // 结果 ~F?s\kp6
K.c6n,'
/** 8<ZxE(v
* 结果总数 =!m5'$Uz>
*/ I*_@WoI*
publicint getCount(){ ^c3~CD5H
3
return count; 6KPM4#61o
} ;$Q`JN=
bI.LE/yk
publicvoid setCount(int count){ eeb`Ao
this.count = count; rtf\{u9 }g
} X[b= 25Ct
1 zIFQ@
/** 3/V&PDC*'
* 本结果所在的页码,从1开始 .w3.zZ0[
* vcs=!Ace
* @return Returns the pageNo. R{GOlxKs C
*/ q15t7-Z6
publicint getP(){ PPO*&=!]
return p; aOHf#!/"sb
} d:*,HzG
^lhV\YxJ
/** j*@^O`^v
* if(p<=0) p=1 -L@4da[]i
* Xh"JyDTj3
* @param p NfizX!w&
*/ )*@n G$i99
publicvoid setP(int p){ 3wK{?
if(p <= 0) }}y$T(:l
p = 1; X@KF}x's
this.p = p; p\OUx Am
} =Tv|kJ|
j
?t++IEoP
/** 8o43J;mA
* 每页记录数量 AE!DftI
*/ -(9>{!",J
publicint getNum(){ %D_2;
return num; m UY+v>F
} `s93P^%
/.r|ron:e
/** |kJ'FZZd
* if(num<1) num=1 =W'a6)WE
*/ %PozxF:
publicvoid setNum(int num){ N>##}i
if(num < 1) 9}^nozR,I
num = 1; ;0DTf
this.num = num; 3T^f#UT
} -N;$L~`iAt
l&l&eOE
/** UFBggT\
* 获得总页数 SV#$Cf g
*/ 734)s
publicint getPageNum(){ d_s=5+Yj
return(count - 1) / num + 1; P{j2'gg3
} g&eIfm
i]&C=X
/** `|?K4<5|
* 获得本页的开始编号,为 (p-1)*num+1 )90 Q
*/ E~vM$$O$
publicint getStart(){ tY~gn|M
return(p - 1) * num + 1; e;L++D
} =K'X:UM
5{nERKaPf
/** |#9Nu9ak
* @return Returns the results. xUl=N
*/ ?WPuTPw{
publicList<E> getResults(){ EH{m~x[Ei
return results; ~L\KMB/9e=
} |Iei!jm
"ee:Z_Sz
public void setResults(List<E> results){ ybLl[K(D=
this.results = results; 2F*spu
} d-/{@
3cfJ(%'X
public String toString(){ "(bnr0
StringBuilder buff = new StringBuilder YaiogA
Xc"l')1H
(); MLwh&I9)
buff.append("{"); ZL/iX~}a'
buff.append("count:").append(count); {8+FxmH
buff.append(",p:").append(p); -]yM<dP
buff.append(",nump:").append(num); 8R?X$=$]!.
buff.append(",results:").append "Bl]_YPv
dr3j<D-Q
(results); cmG*"
buff.append("}"); v2=Iqo
return buff.toString(); :[![9JS/
} @qj4rt"
|f5WN&c
} 32h}+fd
l;{n"F
{wsO8LX