Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 nB>C3e
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =wEU+R_#o
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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 ^VabXGzo#
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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 :@K1pAh 4
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分页支持类: :%!`R72
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java代码: 2"~|k_
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package com.javaeye.common.util; Ls51U 7
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import java.util.List; F)XO5CBK
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publicclass PaginationSupport { },#@q_E
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publicfinalstaticint PAGESIZE = 30; =zBc@VTp
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privateint pageSize = PAGESIZE; Y~,ZBl,
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privateList items; ,0k3Qi%
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privateint totalCount; x:dI :G
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privateint[] indexes = newint[0]; A43 mX!g\
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privateint startIndex = 0; n06T6oc
}*Z *wC
public PaginationSupport(List items, int uPh/u!
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totalCount){ pd%h5|*n;
setPageSize(PAGESIZE); 'fo.1
setTotalCount(totalCount); ):<9j"Z;At
setItems(items); {zha jY7
setStartIndex(0); ny++U;qi
} NRIp@PIF:"
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public PaginationSupport(List items, int 2d:IYCl4q
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totalCount, int startIndex){ K-X@3&X}
setPageSize(PAGESIZE); Q&\(m[:)
setTotalCount(totalCount); hsCts@R
setItems(items); nI0TvBD
setStartIndex(startIndex); zfGS=@e]G
} LKX; ^
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public PaginationSupport(List items, int nNj<!}HvV
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totalCount, int pageSize, int startIndex){ VelR8tjP
setPageSize(pageSize); ais@|s;
setTotalCount(totalCount); crvq]J5
setItems(items); "1I\~]]
setStartIndex(startIndex); @vHj>N
} ,2>nr goM
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publicList getItems(){ p#A{.6Pa:
return items; OUM^u*
} MqKf'6z
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publicvoid setItems(List items){ 6O@/Y;5i
this.items = items; u*w'.5l
} 4s_|6{ANS
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publicint getPageSize(){ ZkA05wPZ#
return pageSize; 0cF+4,5
} .+#<~Jv
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publicvoid setPageSize(int pageSize){ Thc"QIk&4
this.pageSize = pageSize; !TwH;#U w
} ,Y+J.8.H
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publicint getTotalCount(){ J}?:\y<
return totalCount; QJ%[6S
} -h%!#g
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publicvoid setTotalCount(int totalCount){ 9fhgCu]$
if(totalCount > 0){ 8
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this.totalCount = totalCount; | >
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int count = totalCount / ]:g;S,{
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pageSize; 'O:QS)
if(totalCount % pageSize > 0) x )w6
count++; 9$Dsm@tX
indexes = newint[count]; Z23*`yR
for(int i = 0; i < count; i++){ VC T~"T2R
indexes = pageSize * Bk44 wz2X
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} z
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}else{ =}pPr]Cc
this.totalCount = 0; ;)7 GdR^K
} V7}3H2]^
} d(t$riFX}
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publicint[] getIndexes(){ f#>ubmuI^
return indexes; 31-:xUIX
} w+_pq6\V
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publicvoid setIndexes(int[] indexes){ vQ_D%f4;
this.indexes = indexes; Y(U+s\X
} QA"mWw-Ds
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publicint getStartIndex(){ j-}WA"
return startIndex; 77?D
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} F?y4 L9|e
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publicvoid setStartIndex(int startIndex){ ]IQ`.:g=9
if(totalCount <= 0) 3;-P (G@
this.startIndex = 0; ]f}#&]<(T
elseif(startIndex >= totalCount) iD"9,1@~n
this.startIndex = indexes .$~zxd#zo
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[indexes.length - 1]; :=cZ,?PQp1
elseif(startIndex < 0) c7~>uNgJ
this.startIndex = 0; @w[2 BaDt
else{ drkY~!a
this.startIndex = indexes bw[s<z|LKA
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[startIndex / pageSize]; u|eV'-R)s
} zQ>|`0&8
} a`t<R
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publicint getNextIndex(){ W3~xjS"h
int nextIndex = getStartIndex() + xp68-&
*;u'W|"/~
pageSize; }bA@QEJ
if(nextIndex >= totalCount) 93]67PL#+
return getStartIndex(); 'jr[
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else -RK R.,
return nextIndex; ZOIx+%/Vd#
} X8uAwHa6F
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publicint getPreviousIndex(){ 7}%Z>
int previousIndex = getStartIndex() - fC<pCdsg
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pageSize; h,!`2_&UQ
if(previousIndex < 0) 9o<5Z=
return0; Rv=rO|&]
else 7,BULs\g
return previousIndex; L!l`2[F|
} kWW$*d$
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} vlSSw+r9
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抽象业务类 HCIS4}lQ
java代码: aFf(m-
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/** xk\n F0z
* Created on 2005-7-12 H7Y :l0b
*/ 0~( f<:
package com.javaeye.common.business; Z6\H4,k&
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import java.io.Serializable; cy{ ado2
import java.util.List; ?VRf5 Cr-
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import org.hibernate.Criteria; L[rxs[7~
import org.hibernate.HibernateException; tH^]`6"QUa
import org.hibernate.Session; q!!gn1PT(T
import org.hibernate.criterion.DetachedCriteria; DYej<T'?3
import org.hibernate.criterion.Projections; DGrk}
import JC#M,j2
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org.springframework.orm.hibernate3.HibernateCallback; b2vCr F;
import o4F?Rx,L
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org.springframework.orm.hibernate3.support.HibernateDaoS FzM<0FJRX
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upport; mR3-+dB/
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import com.javaeye.common.util.PaginationSupport; C;jV)hr6P
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public abstract class AbstractManager extends ^X\SwgD2w
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HibernateDaoSupport { 5u=$m^@{
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privateboolean cacheQueries = false; 7%)KB4(\_
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privateString queryCacheRegion; u!@(u!Qz
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publicvoid setCacheQueries(boolean B$D7}=|kc
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cacheQueries){ yO*HJpc
this.cacheQueries = cacheQueries; kC8M2 |L
} ==]BrhZK
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publicvoid setQueryCacheRegion(String ~/m=Q<cV
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queryCacheRegion){ 9ymx;
this.queryCacheRegion = W\1V`\gF
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queryCacheRegion; 0/TP`3$X#"
} efXiZ
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publicvoid save(finalObject entity){
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getHibernateTemplate().save(entity); Q4e+vBECkq
} 2Y1y;hCK
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publicvoid persist(finalObject entity){ X')t6DQ( I
getHibernateTemplate().save(entity); }BN!Xa
} 0 P2lq
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publicvoid update(finalObject entity){ pSKwXx
getHibernateTemplate().update(entity); N;mJHr3[F
} 5v_vv'~
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publicvoid delete(finalObject entity){ o~`KOe
getHibernateTemplate().delete(entity); yBkcYHT
} 6R'z3[K9
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publicObject load(finalClass entity, <sw fYT!N
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finalSerializable id){ Qr9@e Q1Pp
return getHibernateTemplate().load q5#6PYIq
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(entity, id); PUbfQg
} FT[of(g^
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publicObject get(finalClass entity, ^`+Kjhht
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finalSerializable id){ S(#v<C,hd
return getHibernateTemplate().get ]Il}ymkIZ
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(entity, id); k, >*.Yoh
} (MzThGJK_
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publicList findAll(finalClass entity){ y"Ios:v@-
return getHibernateTemplate().find("from %v)+]Ds{
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" + entity.getName()); ap wA
} F#KUu3;B
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publicList findByNamedQuery(finalString p>h}k_s
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namedQuery){ [pX cKN
return getHibernateTemplate V i<6i0
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().findByNamedQuery(namedQuery); THy{r_dx
} '4)4* 3z,
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publicList findByNamedQuery(finalString query, bZ[ay-f6oK
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finalObject parameter){ UFGUP]J>
return getHibernateTemplate bPA1>p7
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().findByNamedQuery(query, parameter); fRK=y+gl@
} ~u-_DOA
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publicList findByNamedQuery(finalString query, <tgfbY^nL
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finalObject[] parameters){ [13NhF3.P
return getHibernateTemplate D:0?u_[W
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().findByNamedQuery(query, parameters); 1
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} %@^9(xTE
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publicList find(finalString query){ Y/]J0D
return getHibernateTemplate().find xp%LXxj
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(query); 2Q)pT$
} 8d[!"lL
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publicList find(finalString query, finalObject S9{&.[O
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parameter){ 4$^rzAi5
return getHibernateTemplate().find HE@P<
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(query, parameter); i?n#ge
} 9)J)r\
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public PaginationSupport findPageByCriteria 91|~KR)
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(final DetachedCriteria detachedCriteria){ #B@*-
return findPageByCriteria JlE b
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); s)}EMDY
} N**"u"CX
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public PaginationSupport findPageByCriteria ^~W s4[Guo
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(final DetachedCriteria detachedCriteria, finalint ,
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startIndex){ xM13OoU
return findPageByCriteria 8X)1bNGqhe
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(detachedCriteria, PaginationSupport.PAGESIZE, 1?{w~cF}
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startIndex); zTg&W7oz
} e_dsBmTh
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public PaginationSupport findPageByCriteria J<-2dvq
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(final DetachedCriteria detachedCriteria, finalint xbsX-F
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pageSize, D)bR-a_^
finalint startIndex){ dF'oZQz
return(PaginationSupport) iCdq-r/r!6
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getHibernateTemplate().execute(new HibernateCallback(){ gsVm)mkd
publicObject doInHibernate oB%j3aAH
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(Session session)throws HibernateException { .83z =
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); seA=7c5E
int totalCount = /OeOL3Y
tx]!|x" F
((Integer) criteria.setProjection(Projections.rowCount M[6WcH0/T
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()).uniqueResult()).intValue(); 9`G}GU]@}
criteria.setProjection !uN_<!
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(null); *wV`7\@
List items = L87=*_!B;
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criteria.setFirstResult(startIndex).setMaxResults >:P-3#e*
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(pageSize).list(); Jqqt@5Ni
PaginationSupport ps = g&O!w!T
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new PaginationSupport(items, totalCount, pageSize, -XWlmw*i(g
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startIndex); 7F8>w 7Y]
return ps; ^vc#)tm5p
} L lVE5f?
}, true); 6]Ri$V&"
} wu19Pg?F
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public List findAllByCriteria(final uEdeA'*^
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DetachedCriteria detachedCriteria){ +Ec@qP R&
return(List) getHibernateTemplate @^^,VgW[
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().execute(new HibernateCallback(){ |1UJKJwX
publicObject doInHibernate 92g&,Wb
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(Session session)throws HibernateException { MJG)fFl]O
Criteria criteria = nj7\vIR7
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detachedCriteria.getExecutableCriteria(session); c'Zs2s7$
return criteria.list(); wsAijHjJI!
} -4t!k
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}, true); OB\jq!"
} JV;-P=o1B
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public int getCountByCriteria(final 7_ao?}g
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DetachedCriteria detachedCriteria){ ~4u[\&Sh
Integer count = (Integer) 6q@VkzF
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getHibernateTemplate().execute(new HibernateCallback(){ U[c^xz&
publicObject doInHibernate jmva0K},SE
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(Session session)throws HibernateException { pR7 D3Q:^7
Criteria criteria = lU% L
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detachedCriteria.getExecutableCriteria(session); {KM5pK?,BJ
return q|kkdK|N/Y
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criteria.setProjection(Projections.rowCount kUQdi%3yY;
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()).uniqueResult(); 9Xeg&Z|!
} THz=_L6
}, true); IW- BY =C
return count.intValue(); 1n EW'F
} L=<{tzTc
} ;p/$9b.0:
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用户在web层构造查询条件detachedCriteria,和可选的 nVv=smVOt
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _kJW/3eE
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PaginationSupport的实例ps。 1|3{.Ed
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ps.getItems()得到已分页好的结果集 KU)~p"0[6]
ps.getIndexes()得到分页索引的数组 ^fT?(y_=e
ps.getTotalCount()得到总结果数 ^y3snuLtE
ps.getStartIndex()当前分页索引 +4m~D`fqt[
ps.getNextIndex()下一页索引 uz[5h0c
ps.getPreviousIndex()上一页索引 mNnt9F3Eq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -`} d@x
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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 'I1^70bB
EHcgWlTu
一下代码重构了。 f)%8*B
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我把原本我的做法也提供出来供大家讨论吧: 7&{[Y^R]"
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首先,为了实现分页查询,我封装了一个Page类: &/tGT3)
java代码: o+
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/*Created on 2005-4-14*/ I.RmBUq):s
package org.flyware.util.page; WR@TH
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/** ieG%D
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* @author Joa pZO`18z
* ^Yu%JCN8g
*/ D}6~2j
publicclass Page { CiTjRJ-ZW)
pv){R;f
/** imply if the page has previous page */ w8>
privateboolean hasPrePage; t&L+]I'P3
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/** imply if the page has next page */ p:CpY'KV_
privateboolean hasNextPage; D+xHTQNTL
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/** the number of every page */ R3ru<u>k&
privateint everyPage; 6;vfl*
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/** the total page number */ <zh N7="
privateint totalPage; C
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/** the number of current page */ "0#d F:qt
privateint currentPage; H:>i:\J/M9
*mTx0sQz(J
/** the begin index of the records by the current 1Wy0#?L
N)N\iad^
query */ y:+4-1
privateint beginIndex; f*&4d
y?*4SLy
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/** The default constructor */ Zcg@]Sx(I
public Page(){ K84VeAe
f hS4Gb_
} z6f N)kw
szW85{<+
/** construct the page by everyPage u AmDXqJ3
* @param everyPage BT8L 'qEj
* */ 8s#2Zv
public Page(int everyPage){ ae`6hW2
this.everyPage = everyPage; ,z+7rl
} X23#y7:
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/** The whole constructor */ %an&lcoX
public Page(boolean hasPrePage, boolean hasNextPage, N% W298
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,
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int everyPage, int totalPage, "[t (u/e
int currentPage, int beginIndex){ (c=.?{U
this.hasPrePage = hasPrePage; E+xC1U
3
this.hasNextPage = hasNextPage; HbXYinG%
this.everyPage = everyPage; p&|:,|jo5
this.totalPage = totalPage; ytg' {)
this.currentPage = currentPage; JXA!l?%
this.beginIndex = beginIndex; !<2%N3l
} Mp`2[S@$
TowRY=#jiS
/** N(@B3%H2/J
* @return #`(-Oj2hH
* Returns the beginIndex. MX\v2["FoV
*/ ;+-Dg3
publicint getBeginIndex(){ sF+Bu'9A
return beginIndex; b6y/o48
} y2:~_MD
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/** a8wQ,
* @param beginIndex m^M sp:T,
* The beginIndex to set. +#a_Y
*/ \Q m1+tg
publicvoid setBeginIndex(int beginIndex){ M!j: 2dT"
this.beginIndex = beginIndex; 7 _*k<W7|
} ]> dCt<
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/** AYnk.H-v
* @return -cqR]'u
* Returns the currentPage. 9p{7x[ C
*/ r{pbUk
publicint getCurrentPage(){ *t3uj
return currentPage; *[SOz)
} PUJkC
48 n5Y~YS
/** gcKXda(
* @param currentPage >.X& v
* The currentPage to set. ?\7$63gBH
*/ !:<(p
publicvoid setCurrentPage(int currentPage){ #Z)8,N
this.currentPage = currentPage; V+'C71-P
} DN%b!K:
pni*#W*n
/** @W+m;4 HH
* @return oFC]L1HN&
* Returns the everyPage. :,'yHVG\
*/ H;.${u^lhd
publicint getEveryPage(){ n
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return everyPage; Op2@En|d
} `1fNB1c
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/** V^[B=|56
* @param everyPage Q]v><
* The everyPage to set. n |e=7?H8
*/ +8#hi5e
publicvoid setEveryPage(int everyPage){ zOfMKrRG
this.everyPage = everyPage; P/e6b
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} gXP)YN
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/** M8p6f)l3
* @return Y;dQLZCC
* Returns the hasNextPage. eF%>5
*/ cFF'ygJ/
publicboolean getHasNextPage(){ BV@xE
return hasNextPage; ={]tklND
} []I_r=
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/** |Y")$pjz
* @param hasNextPage "gCqb;^
* The hasNextPage to set. CL)*cu6zG
*/ N" =$S|Gs
publicvoid setHasNextPage(boolean hasNextPage){ 9-(
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this.hasNextPage = hasNextPage; BdQ/kXZu+
} }F<=
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/** k`u.:C&
* @return ObyF~j}j
* Returns the hasPrePage. ["65\GI?
*/ DbIn3/WNe
publicboolean getHasPrePage(){ ' ] $mt
return hasPrePage; 5dXDL~/2p
} j
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/** li7"{+ct
* @param hasPrePage L7rH=gZ&!]
* The hasPrePage to set. l =Is-N`
*/ ZtofDp5B
publicvoid setHasPrePage(boolean hasPrePage){ D%%@+3a
this.hasPrePage = hasPrePage; HV}*}Ty
} OB5t+_s
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/** fUV;3du
* @return Returns the totalPage. :% m56
* }xG~a=,
*/ p1`")$
publicint getTotalPage(){ p.@_3^#|
return totalPage; > %B7/l$
} X7Z=@d(
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/** p/WE[8U
* @param totalPage N*NGC!p`N
* The totalPage to set. yZyB.wT
*/ oH>G3n|U^
publicvoid setTotalPage(int totalPage){ _p^&]eQ+k#
this.totalPage = totalPage; agUdPl$e\
} .jK,6't^
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} og)f?4
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 u|EHe"V"
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个PageUtil,负责对Page对象进行构造: G'c6%;0)
java代码: <<~swN
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/*Created on 2005-4-14*/ h4geoC_W2
package org.flyware.util.page; G+V?c1Me
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import org.apache.commons.logging.Log; 5JggU
import org.apache.commons.logging.LogFactory; <F6LC_
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/**
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* @author Joa W>cHZ. _
* m$!Ex}2
*/ r[W
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publicclass PageUtil { sHn-#SGm
gl>%ADOB@
privatestaticfinal Log logger = LogFactory.getLog 7rSads
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(PageUtil.class); #.W^7}H
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/** gv}J"anD
* Use the origin page to create a new page }J m~b9j
* @param page D\-D~G]x
* @param totalRecords >#EOCo
* @return DC+l3N
*/ LnlDCbF;!
publicstatic Page createPage(Page page, int i/{`rv*K[
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totalRecords){ F$nc9x[S
return createPage(page.getEveryPage(), @0&KM|+
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page.getCurrentPage(), totalRecords); vH)V\V
} `Ti?hQm/
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/** 6X[Mn2wYW
* the basic page utils not including exception rGUu K0L&
pZV=Co3!I
handler MYMg/>f[
* @param everyPage :=e"D;5
* @param currentPage ZMGthI}~-
* @param totalRecords C<yjGtVD
* @return page G^&P'*
*/ ?CSv;:
publicstatic Page createPage(int everyPage, int zn2Qp
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currentPage, int totalRecords){ e763yd
everyPage = getEveryPage(everyPage); #CTeZ/g
currentPage = getCurrentPage(currentPage); t~kh?u].j
int beginIndex = getBeginIndex(everyPage, 'H8;(Rw
}zyh!
currentPage); L yNLz
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int totalPage = getTotalPage(everyPage, 7x//4G
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totalRecords); bD4aSubN
boolean hasNextPage = hasNextPage(currentPage, .)[0yW&
.
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totalPage); [/GCy0jk
boolean hasPrePage = hasPrePage(currentPage); n?}7vz;
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returnnew Page(hasPrePage, hasNextPage, @s7wKk
everyPage, totalPage, !.@F,wZvY
currentPage, @G?R(
DTo P|P
beginIndex); 2 i97
} <}('w/
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privatestaticint getEveryPage(int everyPage){ vTq
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return everyPage == 0 ? 10 : everyPage;
kAnK1W>
} .~7:o.BE`n
91\]Dg
privatestaticint getCurrentPage(int currentPage){ Bhg,P.7
return currentPage == 0 ? 1 : currentPage; SI9PgC
} ]CGH )4Pe
[iUy_ C=qp
privatestaticint getBeginIndex(int everyPage, int 7QM1E(cMg
Vl`!6.F3
currentPage){ \kEC|O)8
return(currentPage - 1) * everyPage; LtVIvZie
} )JXy>q#
YES-,;ZQ'
privatestaticint getTotalPage(int everyPage, int h42dk(B
8Bwm+LYr-
totalRecords){ NT;cTa=;
int totalPage = 0; rtC:3fDy
vu|-}v?:
if(totalRecords % everyPage == 0) -h%1rw
totalPage = totalRecords / everyPage; 4gh`
>
else O\q-Ai
totalPage = totalRecords / everyPage + 1 ; Tu&W7aoX5
ufvjW]
return totalPage; !eA6Ejf
} ?L+|b5RS
<m0m8p"G
privatestaticboolean hasPrePage(int currentPage){ \fSo9$
return currentPage == 1 ? false : true; tNC;CP#R+
} ^7iP!-w/
bBgyLyg
privatestaticboolean hasNextPage(int currentPage, {4YD_$4W
e {805^X}
int totalPage){ ,iMdv+
return currentPage == totalPage || totalPage == p@[n(?duC.
+Y"HbNz
0 ? false : true; ra}t#Xt`
} Q=h37]U+
Rgb&EnVW
=i:,")W7=
} {+jO/ZQu5
-7(,*1Tk
d:JP935
wj 15Og?
m_h$fT8
_
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。 Wiere0 2*
}S 6h1X
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 P asVfC@
C"R}_C|r)*
做法如下: &x)n K
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >9,:i)m_
7=a=@D[
的信息,和一个结果集List: 4azqH;i
java代码: lQ!(lPh
~ugH2jiB
Y
lhKP;
/*Created on 2005-6-13*/ bA\(oD+:
package com.adt.bo; xwa@h}\#
k%?qN,Cl
import java.util.List; >/G[Oo
z yrjb8
import org.flyware.util.page.Page; P#-p*4
_@! yj
/**
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* @author Joa to(lE2`.da
*/ q+{yv
publicclass Result { [E)&dl_k
hQwUwfoe@
private Page page; qflOi8
1^tM%2rP'
private List content; ZDx1v_xr
g5lK&-yu]
/** 2)9XTY6$
* The default constructor GC7W7B
*/ yi*EE%
public Result(){ hCob^o
super(); cK\'D
} %|B$y;q^3
5#mHWBGd7
/** TUq
,
* The constructor using fields rm4t
* ~toR)=Yv
* @param page A9y@v{txN
* @param content J~)JsAXAI
*/ &neB$m3y
public Result(Page page, List content){ L~*nI d
this.page = page; A u"BDP
this.content = content; P5__[aTD
} MUUhg
&'u%|A@
/** zqxN/H]z
* @return Returns the content. Lw`}o` D
*/ WF-^pfRq~
publicList getContent(){ K0Lc~n/
return content; 2XyC;RWJ%
} Ymm*p,`
!'Ww%ZL\
/** jvhD_L/
* @return Returns the page. h9QQ8}g
*/ tG[v@-O
public Page getPage(){ ge#P(Itz
return page; oI"gQFGu`u
} tR(L>ZG{
|WSmpuf
/** ~*L@|?
* @param content l"%WXi"X
* The content to set. V o%GO9b;
*/ = Q"(9[Az
public void setContent(List content){ O^IS:\JX&
this.content = content; 3
<Zo{;
} y1#QP3'Z1
2[Xe:)d
/** 06I(01M1
* @param page USH>`3
* The page to set. +1Pu29B0
*/ G$s=P
publicvoid setPage(Page page){ g_?bWm4br
this.page = page; ,irc=0M(
} 4"eeEs h
} hA+;eXy/
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tDtqTB}
Qm4cuV-0{
5Zl7crA [
2. 编写业务逻辑接口,并实现它(UserManager, 1~vv<`-
ZVz*1]}
UserManagerImpl) *}Rd%'
java代码: n"<'F4r
X
[;n149o
Tvw(Sq};
/*Created on 2005-7-15*/ y2Vc[o(NP
package com.adt.service; yppXecFJ
2>.>q9J(
import net.sf.hibernate.HibernateException; l#a*w
Pz-=Eq
import org.flyware.util.page.Page; #!4`t]E<
Mm%b8#Fe!
import com.adt.bo.Result; xI8v'[3
e*o:ltP./
/** P7!gUxcv9Y
* @author Joa \>+BvF
*/ X:W}S/
publicinterface UserManager { r]&&*:
<n0j'P>1
public Result listUser(Page page)throws :KsBJ>2ck
4}Hf"L[ l
HibernateException; Co`:D
X
iM{YZ`B
} ar@ysBy
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#J%Fi).^)
[Rzn>
[}y"rs`!
java代码: kLbo |p"cT
h|ja67VG
@@|H8mP}H
/*Created on 2005-7-15*/ 3Ael
package com.adt.service.impl; %j ?7O00@
>c.HH}O0W
import java.util.List; l6!a?C[2T
r`C t/]c
import net.sf.hibernate.HibernateException; XNkQ0o0
7` t,
import org.flyware.util.page.Page; ? \NT'CG
import org.flyware.util.page.PageUtil; E9j(%kQ2
j{P3o<l&`
import com.adt.bo.Result; 0vM,2:kf*
import com.adt.dao.UserDAO; ;+Mr|vweTC
import com.adt.exception.ObjectNotFoundException; DkBVk+
import com.adt.service.UserManager; e3kdIOu5
IE&G7\>(yO
/** [q!)Y:|u_>
* @author Joa IF3 V5Q
*/ _x?S0R1
publicclass UserManagerImpl implements UserManager { UbSD?Ew@35
(rSBzM]H
private UserDAO userDAO; JDB Ni+t
"`5BAv;u
/** ]j<&
:_
* @param userDAO The userDAO to set. m ,TYF
*/ ooT~R2u
publicvoid setUserDAO(UserDAO userDAO){ IF|%.%I$!U
this.userDAO = userDAO; x[2eA!NC
} .?.Q[ic
|*zvaI(}
/* (non-Javadoc) YQ5d!a.
* @see com.adt.service.UserManager#listUser [RHji47
YCNpJGM
(org.flyware.util.page.Page) XwdehyPhT2
*/ ys|};*
public Result listUser(Page page)throws }ABHGr5[
xiQ;lE
HibernateException, ObjectNotFoundException { tNCKL.yU
int totalRecords = userDAO.getUserCount(); i- r y5x
if(totalRecords == 0) jVdB- y/r
throw new ObjectNotFoundException j~Ubpf
Mhg_z.Z
("userNotExist"); L@6T~
page = PageUtil.createPage(page, totalRecords); _1P8rc"Dx
List users = userDAO.getUserByPage(page); z>W'Ra6
returnnew Result(page, users); *5;#+%A
} WK 6|e[iP
JKs&!!
} ?:sQ]S/Er
^ZO3:"t!w
`Yc>I!iN
X !l#1
4gK_'b6"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +jX.::UPm
l%$co07cX
询,接下来编写UserDAO的代码: (Y]G6>
Oa
3. UserDAO 和 UserDAOImpl: PQ[x A*
java代码: GG[$-
MM4Eq>F/
CEp @-R
/*Created on 2005-7-15*/ > v ]-B"Y
package com.adt.dao; JZB@K6 ~dO
d!]_n|B@9
import java.util.List; D$y-Kh
ziui
import org.flyware.util.page.Page; QOY M/1U
viR-h
iD
import net.sf.hibernate.HibernateException; <3c|S_|L*m
k/V:QdD Sb
/** 1\+d 5Q0
* @author Joa S`GM#( t@_
*/ *Ldno`1O
publicinterface UserDAO extends BaseDAO { C8.MoFfhe
=qVD"Z]z
publicList getUserByName(String name)throws ?]u=5gqUU
{H%1sI
HibernateException; ;]Bkw6o
`@|Kx\y4=j
publicint getUserCount()throws HibernateException; ?AJE*=b
0^rDf
L
publicList getUserByPage(Page page)throws QAh6!<.;@
j#)K/`
HibernateException; 6@o *"4~Q
h ?%]uFJC
} xiG_l-2l
DG"Z: ^`*
\Lu] %}
tB7g.)yZb
iSxuor^;
java代码: j-j,0!T~b
|VD}:
)S6"I
/*Created on 2005-7-15*/ ^J Y]w^u
package com.adt.dao.impl; 73OYHp_j
(Cjw^P|Y@
import java.util.List; _l;$<]re\k
E<XrXxS1O
import org.flyware.util.page.Page; g}=opw6z
<rpXhcR
import net.sf.hibernate.HibernateException; )w++cC4/5
import net.sf.hibernate.Query; :=K <2
byUstm6y
import com.adt.dao.UserDAO; B)4>:j:{?W
)mw&e}jRV
/** L cpz(W^
* @author Joa {Jj
vF
*/ h^$c
public class UserDAOImpl extends BaseDAOHibernateImpl VDP \E<3"
2{o
e J
implements UserDAO { 0*Is#73rjY
jVtRn.qh
/* (non-Javadoc) m'i^BE
* @see com.adt.dao.UserDAO#getUserByName R59'KR2?
52JtEt7E
(java.lang.String) 0QxE6>xL=
*/ =^LX,!2zp{
publicList getUserByName(String name)throws >AT T<U=
V;#bcr=Z<J
HibernateException { sjj*7i*
String querySentence = "FROM user in class e2PM^1{_
`vPc&.-K
com.adt.po.User WHERE user.name=:name"; !DUC#)F
Query query = getSession().createQuery 5E!G
APA:K9jD
(querySentence); ;<=B I!
query.setParameter("name", name); ~'9>jpnw
return query.list(); Ev7fvz =
} .j)f'<;%
b:w {7
/* (non-Javadoc) ZNEWUt{+;^
* @see com.adt.dao.UserDAO#getUserCount() ~Z#jIG<?g
*/ g/ict2!
publicint getUserCount()throws HibernateException { 9cm9;
int count = 0; D8''q%
String querySentence = "SELECT count(*) FROM x)<Hr,wd
R~R ?0aq
user in class com.adt.po.User"; h#>%\Pvt;
Query query = getSession().createQuery <)
`?s
Y([YDn
(querySentence); .oNs8._:
count = ((Integer)query.iterate().next d]*a:>58
TE.O@:7Z
()).intValue(); ZOK,P
return count; Dqw?3 KB
} Z/S7ei@56
VTt{0 ~
/* (non-Javadoc) QP{V
* @see com.adt.dao.UserDAO#getUserByPage +$F_7Hx
ny]R,D0
(org.flyware.util.page.Page) n(MVm-H
*/ /.u0rxoRP}
publicList getUserByPage(Page page)throws >[ox|_o
?Hd/!I&
HibernateException { mw*BaDN@Q
String querySentence = "FROM user in class viJK%^U=-
wA#w]8SM
com.adt.po.User"; 1[;~>t@C
Query query = getSession().createQuery 4/Yk;X[jk
5fdB<& 9
(querySentence); XOe8(cXa9
query.setFirstResult(page.getBeginIndex()) C;6Nu W
.setMaxResults(page.getEveryPage()); fQ,L~:Y =
return query.list(); rIt#ps
} 8JU9Qb]L'I
?<iinx
} Oa'DVfw2J
,L"1Ah
|9F^"7Q~C
w<ol$2&B
m*d {pX
至此,一个完整的分页程序完成。前台的只需要调用 Yc,qXK-
B7fV_-p: G
userManager.listUser(page)即可得到一个Page对象和结果集对象 [JY 1| N
bH-QF\>
的综合体,而传入的参数page对象则可以由前台传入,如果用 cq=ker zQ
Nx8~Rn
webwork,甚至可以直接在配置文件中指定。 ~P47:IZf
i@C1}o-/
下面给出一个webwork调用示例: Oz[]]`C1
java代码: jx3J$5
cBO.96ZHE
&pCNOHi|
/*Created on 2005-6-17*/ [a<ucJ
package com.adt.action.user; &C.{7ZNt
8~=<!(M)m/
import java.util.List; 'TF5CNX
02lI-xHe
import org.apache.commons.logging.Log; Vk/!_)
import org.apache.commons.logging.LogFactory; 1FCHqqZ=
import org.flyware.util.page.Page; /7nircXj@
\=O[' #
import com.adt.bo.Result; Y'YvVI
import com.adt.service.UserService; NT^m.o~4
import com.opensymphony.xwork.Action; 8<Y*@1*j
W?n)IBj8
/** .@3
* @author Joa tf VK
*/ INd:_cT4l
publicclass ListUser implementsAction{ i58&o@.H<u
VuOZZ7y
privatestaticfinal Log logger = LogFactory.getLog =peodj^
fr\"MP
(ListUser.class); H} R/_5g
fq@r6\TI
private UserService userService; zJH#J=O
B~[QmK
private Page page; ]Cfjs33H
OM]d}}=Y
privateList users; s7A3CY]->
yl>V'
/* %[<@$qP
* (non-Javadoc) )<?^~"h
* g69^D
* @see com.opensymphony.xwork.Action#execute() ]Kutuf$t
*/ Md4hd#z
publicString execute()throwsException{ HinPO
Result result = userService.listUser(page); mzh8<w?ns
page = result.getPage(); {<~oa+"
users = result.getContent(); $S_xrrE#
return SUCCESS; M x/G^yO9
} :7,j%ELic
}=dUASL
/** &%@b;)]J
* @return Returns the page. B# >7;xy>
*/ qHZ!~Kq,"'
public Page getPage(){ ^ZxT0oaL
return page; w)#Lu/
} v0D~zV"<y
Yq6e=?-
/** M+7&kt0;
* @return Returns the users. A5UZUU^
*/ \gBsAZE
publicList getUsers(){ @O!BQ^'hk#
return users; !O`aaLc
} Lp|7s8?
<|!?V"`3
/** Hwz.5hV"
* @param page eHQS\n
* The page to set. t",=]k
*/ iI!MF1
publicvoid setPage(Page page){ f,jN"
this.page = page; \jkMnS6FvL
} >@g+%K]
HX;JO[0
/** \E(Negt7
* @param users ` XvuyH
* The users to set. n=z=%T6
*/ Ft<6`C
publicvoid setUsers(List users){ %4=r .9
this.users = users; U<YP@?w
} $?HOke
n A<#A
/** F}f/cG<X
* @param userService c'wxCqnE
* The userService to set. Y<]A5cm
*/ w$aiVOjgT
publicvoid setUserService(UserService userService){ X6T*?t3!9[
this.userService = userService; \>DMN #
} U,tl)(!@Q-
} W
Ai91K@
d)R7#HLZ7
CeZ+!-lG
S'h{["P~
0
q':P9o*N?
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, =tKb7:KU
(GeOD V?U
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 hxB`
hu-
`kRv+Qwfa
么只需要: e5s=@-[
java代码: W$>AK_Y}
_^k9!Vjo
F>H5 ww9E
<?xml version="1.0"?> Rv/=bY
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $:RP tG
3axbWf3[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *_ U=KpZF
R7
WGc[
1.0.dtd"> r(VGdG
Ft[)m#Dj`
<xwork> tO@n3"O
?V{APM$x
<package name="user" extends="webwork- j><8V Qx
b 9%G"?~Zz
interceptors"> X!AD]sK
GyVRe]<>B
<!-- The default interceptor stack name Edp%z"J;C
,&q
Q[i
--> z'!sc"]W6
<default-interceptor-ref Ec/-f`8
mu>L9Z~(L_
name="myDefaultWebStack"/> i?+>,r@\p
A*a:#'"*N
<action name="listUser" >!gW]{
wn&5Ul9Elb
class="com.adt.action.user.ListUser"> UNC%<=
<param b~u53
Qp5YS
name="page.everyPage">10</param> j1sgvh]D
<result [b?[LK}.
{ch+G~oS
name="success">/user/user_list.jsp</result> skeXsls
</action> Q+ogV vMq>
m~<<ok_
</package> u&Lp
1UwpLd
</xwork> =iFI@2
m35$4
M,R**z
RHIGNzSz
YM`I&!n
5ieF8F%
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 OngUZMgdb
^rX5C2}G\D
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 }TDoQ]P
C}D\^(nLu.
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 B']}n`g
"Ei' FM
BM+>.
{I9<W'k{
i\yp(tE%^
我写的一个用于分页的类,用了泛型了,hoho _KSlIgQ
}0
@@QB,VS;{<
java代码: ol #4AU`
so]p1@K
RX cfd-us
package com.intokr.util; FhAYk
Dx*tolF
import java.util.List; !=B=1th4
S4!}7NOh
/** #sJL"GB
* 用于分页的类<br> ~1g)4g~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> /f Ui2[y
* SbX#$; ks~
* @version 0.01 ^dP]3D1
@
* @author cheng 4^uwZ:
*/ )"sJaHx<
public class Paginator<E> { Pg%k>~i
privateint count = 0; // 总记录数 3$#=*Zp
privateint p = 1; // 页编号 loByT
p
^
privateint num = 20; // 每页的记录数 .Z#8,<+
privateList<E> results = null; // 结果 F./$nwb
~z$+uK
/** }Lc8tj<
* 结果总数 0\tdxi
*/ TMAart;<
publicint getCount(){ 3zsjL=ta
return count; 032PR;]
} A`
)A=L
eZ`x[g%1
publicvoid setCount(int count){ $:!L38[7$
this.count = count; 0WO-+eRB/
} %&\DCAFk
X6SqOb\(a
/** Z-;I,\Y%
* 本结果所在的页码,从1开始 (! "+\KY
* j#D (
</T
* @return Returns the pageNo. .'Rz
tBv
*/ v_L?n7c
publicint getP(){ 'ngx\Lr
return p; 7a5G,C#QQ
} UkzLUok]U
.J fV4!=o
/** (|t)MnPfY
* if(p<=0) p=1 <HMmsw
*
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* @param p ,Z aPY
*/ ki<4G
publicvoid setP(int p){ yh{Wuz=T
if(p <= 0) &:}}T=@M1
p = 1; ^QbaMX
this.p = p; M?G4k]
} -xMM}r
y
T.B}k`$
/** *R8qnvE\()
* 每页记录数量 M7.
fz"M
*/ 1Uf8ef1,
publicint getNum(){ m>8tA+K)+)
return num; 1WJ%n;
} ,mm9X\ '
a0*qK)gH
/** )sBbmct_S
* if(num<1) num=1 :j[a X7Sq2
*/ c,FhI~>R
publicvoid setNum(int num){ vI1UFD
D
if(num < 1) 5nh:S0M6V
num = 1; -gR
}^D
this.num = num; e,I{+^P
} >X0c:pPu
T*v@hbJ
/** b_%W*Q
* 获得总页数 8B"my\
*/ 6Cvg-X@
publicint getPageNum(){ >#8J@=iuqv
return(count - 1) / num + 1; DfX}^'#m+
} "Qfw)!#
]~J.YX9ST
/** Qu6Q)dZ<
* 获得本页的开始编号,为 (p-1)*num+1 UukHz}(E
*/ ~RIn7/A
publicint getStart(){ 1EcXvT=
return(p - 1) * num + 1; n1+,Pe*)
} bP3S{Jt-|
^_o9%)RL(
/** F]k$O $)0
* @return Returns the results. zbyJ5~
*/ xjO((JC
publicList<E> getResults(){ s\dhQZ w3
return results; $bo 5:c
} HS[N]'dc
t]PO4GA
public void setResults(List<E> results){ UCDvN
this.results = results; u[yUUYe
} ?KF.v1w7
]id5jVY
public String toString(){ zyF[I6Gs
StringBuilder buff = new StringBuilder *oP&'$P
o^b4l'&o
(); .X(*mmH
buff.append("{"); Ii4lwZnz
buff.append("count:").append(count); mIUpAOC`"Z
buff.append(",p:").append(p); &]euL:C
buff.append(",nump:").append(num); \ 5=fC9*G
buff.append(",results:").append 'l`T(_zL\%
+ jIE,N
(results); q)E
J?-
buff.append("}"); RiNKUk{-
return buff.toString(); j_Z"=
} ^d[s*,i?
6D n[9V
} )Og,VXEB
KtY_m`DY4R
ecl$z6'c