Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9+ |W;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (L:Mdo
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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 H-mQ{K^
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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 syCT)}T6z
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。 vOv"^X
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分页支持类: Q:Ma3El\
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java代码: NMUF)ksjN
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package com.javaeye.common.util; +.zX?}
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import java.util.List; gw^W6v
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publicclass PaginationSupport { Q\N >W+d
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publicfinalstaticint PAGESIZE = 30; N6> rU
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privateint pageSize = PAGESIZE; u=Xpu,q
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privateList items; *$Zy|&[Z
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privateint totalCount; I'[;E.KU
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privateint[] indexes = newint[0]; umCmxmr&
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privateint startIndex = 0; \fp'=&tp~a
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public PaginationSupport(List items, int A4Q{(z-?
"=LeHY=9
totalCount){ KtArV
setPageSize(PAGESIZE); HZ1 nuA
setTotalCount(totalCount); \:+ NVIN
setItems(items); =woP~+
setStartIndex(0); dI>cPqQ
} :jC$$oC].
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public PaginationSupport(List items, int mF
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totalCount, int startIndex){ sL;;'S&
setPageSize(PAGESIZE); <[ u(il
setTotalCount(totalCount); GVfRy@7n
setItems(items); ddd2w
setStartIndex(startIndex); VTY # {
} v=Q!ioE7
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public PaginationSupport(List items, int -*OL+
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totalCount, int pageSize, int startIndex){ z, FPhbFn
setPageSize(pageSize); 1/&^~'
setTotalCount(totalCount); ~z")';I|
setItems(items); 3Tp8t6*nL
setStartIndex(startIndex); <N>7.G
} g_Rp}6g
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publicList getItems(){ \v$zU
return items; rhZp
} 7U^{xDg.b
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publicvoid setItems(List items){ oOaLD{g>
this.items = items; ^bfU>02Q6p
} 4wGBB{X
Cl3L)
publicint getPageSize(){ Br.UN~q
return pageSize; MZxU)QW1
} '=xO?2U-Z
72_+ b
publicvoid setPageSize(int pageSize){ ,Q.[Lc=w
this.pageSize = pageSize; TjI&8#AWBA
} rY8(`a
S9ic4rcd
publicint getTotalCount(){ 4bL? V^@7
return totalCount; Z^=(9:
} 2##mVEo.(
h7@%}<%
publicvoid setTotalCount(int totalCount){ .J8 gW
if(totalCount > 0){ 0AF,} &$
this.totalCount = totalCount; TBky+]p@
int count = totalCount / ` N
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Q7{{r&|t&
pageSize; +$#XV@@~
if(totalCount % pageSize > 0) aof'shS8
count++; b5I 8jPj4c
indexes = newint[count]; gm=C0Sp?
for(int i = 0; i < count; i++){ ecO$L<9>
indexes = pageSize * ;PnN$g]Q
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i; ]6s/y
} :SWrx MT
}else{ /-t!)_zvw
this.totalCount = 0; l*huKSX}
} eVB43]g
} }2:q#}"
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publicint[] getIndexes(){ y7+n*|H
return indexes; D:?"Rf{)
} !%DE(E*'(
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publicvoid setIndexes(int[] indexes){ Nl/
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this.indexes = indexes; H q?F @X
} 7i'clB9!
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publicint getStartIndex(){ N}<!k#d
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return startIndex; ~4Mz:h^
} *5?Qam3
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publicvoid setStartIndex(int startIndex){ p$= 3$I
if(totalCount <= 0) -AU'1iRcK7
this.startIndex = 0;
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elseif(startIndex >= totalCount) [*I7^h%
this.startIndex = indexes qn{4AWmJ
%s9*?6
[indexes.length - 1]; @<X[,Mj
elseif(startIndex < 0) ,fN <I
this.startIndex = 0; ZNpC&
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else{ !!8;ZcL}Z
this.startIndex = indexes ZX.,<vumSy
g& f)WQ(
[startIndex / pageSize]; |1/8m/2Af.
} Aq7`A^1t$
} qm'@o -[
9}Za_ZgG
publicint getNextIndex(){ 9`5.0**
int nextIndex = getStartIndex() + Ktvs*.?
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pageSize; p!)tA
if(nextIndex >= totalCount) "Mv^S'?>
return getStartIndex(); Ag*?>I
else ?I:_FT
return nextIndex; Ey%[t
} ?iEn~9WCS
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publicint getPreviousIndex(){ "}ur"bU1
int previousIndex = getStartIndex() - gB+CM?
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ygX!'evY
pageSize; c* ~0R?
if(previousIndex < 0) *~cNUyd
return0; Ov4 [gHy&
else J7e/+W~
return previousIndex; g>'6"p;
} H 8 66,]
c,ct=m.|6A
} &B=z*m
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抽象业务类 WE_'u+!B
java代码: sSD&'K=lq
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/** AW9%E/{
* Created on 2005-7-12 DT6BFx
*/ ,?Vxcr
package com.javaeye.common.business; +u t%C.1
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import java.io.Serializable; n<HF]
import java.util.List; yp@cn(:~
\IzZJGi
import org.hibernate.Criteria; 9$VdYw7D
import org.hibernate.HibernateException; u`oJ3mS;
import org.hibernate.Session; {ehYE ^%N
import org.hibernate.criterion.DetachedCriteria; x^Qij!mB%
import org.hibernate.criterion.Projections; gvo5^O+)HH
import uH7rt
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org.springframework.orm.hibernate3.HibernateCallback; .>PwbZ
import jv1p'qs4
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org.springframework.orm.hibernate3.support.HibernateDaoS Z/v )^VR
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upport; 5H 1x-b
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import com.javaeye.common.util.PaginationSupport; gh"_,ZhZt
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public abstract class AbstractManager extends m}: X\G(6Q
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HibernateDaoSupport { IF//bgk-
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privateboolean cacheQueries = false; 2(e;pM2Dq
Y2N$&]O{
privateString queryCacheRegion; 9c1q:>|
#-R]HLW*
publicvoid setCacheQueries(boolean $U. 2"
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cacheQueries){
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this.cacheQueries = cacheQueries; ,.gJ8p(0x
} r8FAV9A
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publicvoid setQueryCacheRegion(String
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queryCacheRegion){ FgPmQ
this.queryCacheRegion = b+Vlq7Bc
!4t%\N6Ib
queryCacheRegion; |Q?$n3-f"
} [`KQ\4u
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publicvoid save(finalObject entity){ G`;mSq6i
getHibernateTemplate().save(entity); F%{z EANm
} U^-J_yq
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publicvoid persist(finalObject entity){ y4!fu<[i
getHibernateTemplate().save(entity); 'Nx"_jQ
} $Df1t
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publicvoid update(finalObject entity){ uHDUuK:Ur
getHibernateTemplate().update(entity); m^)\P?M5|
} 6e}T
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publicvoid delete(finalObject entity){ nRX<$OzTV
getHibernateTemplate().delete(entity); td#m>S
} +yHzp
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publicObject load(finalClass entity, 7bJM
$
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finalSerializable id){ kaDn=
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return getHibernateTemplate().load
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% %2~%FVb
(entity, id); !yV)EJ:$
} 15DlD`QV
{>brue*)
publicObject get(finalClass entity, y>RqA*J
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finalSerializable id){ ' 94HVag
return getHibernateTemplate().get W}wd?WIps
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(entity, id); ^1--7#H
} UB%;P-RD
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publicList findAll(finalClass entity){ PKs$Q=Ol<|
return getHibernateTemplate().find("from ({!*&DVu
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" + entity.getName()); }yCgd 5+_
} uuCVI2|
_b=})**
publicList findByNamedQuery(finalString x6=tS
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namedQuery){ ^$lsmF]^
return getHibernateTemplate o`}8ZtD
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().findByNamedQuery(namedQuery); zH@+\#M
} ^^)\|kW?
gti=GmL(L
publicList findByNamedQuery(finalString query, $ g#d1u0q
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finalObject parameter){ qZSW5lC0
return getHibernateTemplate $,Y?qn/
9AQ2FD
().findByNamedQuery(query, parameter); Aq/wa6^%
} %5(v'/dQ
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publicList findByNamedQuery(finalString query, uQW d1>
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finalObject[] parameters){ [{_K[5i
return getHibernateTemplate 1+Y;
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().findByNamedQuery(query, parameters); 7|?Ht]
} ,k/<Nv;
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publicList find(finalString query){ wtGb3D"am
return getHibernateTemplate().find lHPhZ(Z
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(query); i"hn%u$V
} P`M1sON~
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publicList find(finalString query, finalObject zPb"6%1B
' }NH$ KA
parameter){ c-a;nAR
return getHibernateTemplate().find %M05& <
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(query, parameter); >[g'i+{
} niM(0p
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public PaginationSupport findPageByCriteria &44?k:
!myF_cv}'
(final DetachedCriteria detachedCriteria){ >Q^*h}IdW
return findPageByCriteria \Ng[lN
qk(u5Z
(detachedCriteria, PaginationSupport.PAGESIZE, 0); * (<3 oIRS
} rB5+~
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public PaginationSupport findPageByCriteria ~9+\
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(final DetachedCriteria detachedCriteria, finalint aeF^&F0
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startIndex){ *yA.D?
return findPageByCriteria 885
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(detachedCriteria, PaginationSupport.PAGESIZE, 2E3x=
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startIndex); ZbcpE~<a
} cY*lsBo
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public PaginationSupport findPageByCriteria ^kpu9H
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(final DetachedCriteria detachedCriteria, finalint 4'#
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pageSize, GpM_Qp
finalint startIndex){ J)Td'iT(
return(PaginationSupport) vweD{\b
=").W \,
getHibernateTemplate().execute(new HibernateCallback(){ eM`"$xc
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publicObject doInHibernate R0mWVgoz
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(Session session)throws HibernateException { u8@>ThPD
Criteria criteria = -n'%MT=Cd
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detachedCriteria.getExecutableCriteria(session); 5=Y\d,SS"
int totalCount = bpeWK&
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((Integer) criteria.setProjection(Projections.rowCount ;rH@>VrR
pF"IDC
()).uniqueResult()).intValue(); Yt;.Z$i ,
criteria.setProjection tI(co5 W
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(null); c^8y/wfok
List items = 7e&%R4{b
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criteria.setFirstResult(startIndex).setMaxResults [t`QV2um
[VP~~*b
(pageSize).list(); 3^zOG2
PaginationSupport ps = %@FTg$
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new PaginationSupport(items, totalCount, pageSize, ysiBru[u
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startIndex); FeFH_
return ps; #VEHyz 6P
} I2'UC)
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}, true); [(N<E/m %B
} %fz!'C_4
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ W7"ks(
return(List) getHibernateTemplate _\LAWQ|M4[
vH#^ |u
().execute(new HibernateCallback(){ Ofg-gCF8
publicObject doInHibernate +d736lLe%
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(Session session)throws HibernateException { Rj=xn(@d
Criteria criteria = pJ5Sxgv{;
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detachedCriteria.getExecutableCriteria(session); y(8AxsROp
return criteria.list(); mko<J0|4
} qyuU
}, true);
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} 5A6d]
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public int getCountByCriteria(final HLU'1As65
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DetachedCriteria detachedCriteria){ {e?D6`#x
Integer count = (Integer) mPxph>o
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getHibernateTemplate().execute(new HibernateCallback(){ 9Qb_BNUo
publicObject doInHibernate yggQ4y6
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(Session session)throws HibernateException { eVDI7W:(Sn
Criteria criteria = *eytr#0B-
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detachedCriteria.getExecutableCriteria(session); x,z +l-y
return NQ!jkojD
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criteria.setProjection(Projections.rowCount DEL#MD!
n-{G19?
()).uniqueResult(); p/xxoU
} Nq)=E[$
}, true); s7<x~v+^
return count.intValue(); FHI`/
} RI"A'/56
} -lm\~VZT3
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用户在web层构造查询条件detachedCriteria,和可选的 Y`3>i,S6\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个
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PaginationSupport的实例ps。 YZdp/X6x
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ps.getItems()得到已分页好的结果集 ]v3 9ag_hu
ps.getIndexes()得到分页索引的数组 tm(.a?p
ps.getTotalCount()得到总结果数 Os@ d&wm
ps.getStartIndex()当前分页索引 Bls\)$
ps.getNextIndex()下一页索引 ayuj)]b
ps.getPreviousIndex()上一页索引 A_}F
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 eW]K~SPd7
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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 B]q
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一下代码重构了。 {
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我把原本我的做法也提供出来供大家讨论吧: _YY:}'+
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首先,为了实现分页查询,我封装了一个Page类: hp!UW
java代码: ` ej
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/*Created on 2005-4-14*/ r"SuE:D
package org.flyware.util.page; yK<%AV@v
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/** JB a:))lw
* @author Joa h&||Ql1
* impzqQlZ,
*/ c.Pyt
publicclass Page {
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/** imply if the page has previous page */ 0 }k[s+^
privateboolean hasPrePage; ig]*Z
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/** imply if the page has next page */ TGGeTtk=
privateboolean hasNextPage; j8!fzJG
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/** the number of every page */ _K>cB<+d
privateint everyPage; 1"009/|
cpp0Y^
/** the total page number */ xCD|UC46?X
privateint totalPage; [ XjJsk,
<*~vZT i(
/** the number of current page */ Qi#%&Jz>f
privateint currentPage; Z16G
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/** the begin index of the records by the current s!``OyI/Z
b&B<'Wb
query */ SY_T\
}
privateint beginIndex; jm'(t=Ze
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/** The default constructor */ *;8tj5du
public Page(){ ZkkXITQkPM
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} /i$E |[
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/** construct the page by everyPage |AW[4Yn>
* @param everyPage P*XLm
* */ K_',Gd4L
public Page(int everyPage){ s={AdQ
this.everyPage = everyPage; hgX@?WWR
} 1 e1$x@\\
IL?3>$,
/** The whole constructor */ v{^_3
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public Page(boolean hasPrePage, boolean hasNextPage, wP- pFc
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int everyPage, int totalPage, deHhl(U;
int currentPage, int beginIndex){ k5]s~*,0
this.hasPrePage = hasPrePage; Mb=vIk{Bf
this.hasNextPage = hasNextPage; n;)!N
this.everyPage = everyPage; snOd
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this.totalPage = totalPage; v-J*PB.0p
this.currentPage = currentPage; ;(fD R8
this.beginIndex = beginIndex; >XjSVRO
} NduvfA4
lwaxj7
/** RxY
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* @return >_(Xb%w
* Returns the beginIndex. "]Wrir?l
*/ +^YXqOXU
publicint getBeginIndex(){ E!&A[TlX\
return beginIndex; -bu.Ar-#;h
} =0TnH<`
mS5'q q;t
/** '+N!3r{G
* @param beginIndex 1w/1k6`0
* The beginIndex to set. }$s#H{T!
*/ %+YLe-\?
publicvoid setBeginIndex(int beginIndex){ \RyOexNZ
this.beginIndex = beginIndex; FA<|V!a
} R<@s]xX_
M5s>;q)
/** j|TcmZGO
* @return I4:4)V?
* Returns the currentPage. {v+,U}
*/ \:-#,( .V
publicint getCurrentPage(){ S(eCG2gR
return currentPage; P7 O$*
} I3]-$
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/** im|(
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* @param currentPage #\[h.4i
* The currentPage to set. Q{T6t;eH
*/ 7T9m@
publicvoid setCurrentPage(int currentPage){ MWl?pG!Y
this.currentPage = currentPage; [X]yj
} KSnU;B6w>
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/** :0x,%V74_!
* @return Y b\t0:_
* Returns the everyPage. wl1i@&9
*/ htX;"R&
publicint getEveryPage(){ DW&%"$2
return everyPage; D*BZp0x
} .|iMKRq
iZ
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/** h3D~?Iom
* @param everyPage \fIGMoy!
* The everyPage to set. A Vf'"~?
*/ UjxEbk5>^
publicvoid setEveryPage(int everyPage){ U>?q|(u
this.everyPage = everyPage; }kzGuNj
} 9W88_rE'e}
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/** NC'+-P'y
* @return 'NHtCs=F
* Returns the hasNextPage. nXPl\|pXt
*/ IV*@}~BJ
publicboolean getHasNextPage(){ al/Mgo
return hasNextPage; 9o5W\.A7[D
} %Z9&z mO
.'N:]G@!
/** ([SrIG> X
* @param hasNextPage \^a(B{
* The hasNextPage to set. t&}Z~Zp
*/ "}
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publicvoid setHasNextPage(boolean hasNextPage){ 2u9O+]EP
this.hasNextPage = hasNextPage; l?Vm/YXb
} ap;?[B~Ga
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/** IX@g].)C
* @return Otq`4 5
* Returns the hasPrePage. /orpQUHA
*/ +c;/hM<IX.
publicboolean getHasPrePage(){ ^*JpdmVhu
return hasPrePage; C_xOk'091
} WeyH;P=
;^+#
/** 8>^(-ca_
* @param hasPrePage mG4$
* The hasPrePage to set. -(*<2Hy4
*/ eS)2#=
publicvoid setHasPrePage(boolean hasPrePage){ x?s5vxAKf
this.hasPrePage = hasPrePage; r*?rwtFtg
} Mx?]7tI
XRoMD6qf;
/** GVS-_KP\
* @return Returns the totalPage. ZccQ{$0H
* Z9Prw/8P
*/
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publicint getTotalPage(){ .G-F5`2I
return totalPage; PL vz1}ts
} T}')QC&wQ
/IQl
/** bz5",8Mn
* @param totalPage
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* The totalPage to set. hLF+_{\C|
*/ LF o{,%B
publicvoid setTotalPage(int totalPage){ j{}-zQ]n
this.totalPage = totalPage; { a2Y7\C/
} 4cZig\mE;
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P
} },1**_#<Br
vn
oI.;H,
dLA'cQId
hv "
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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 @ qFE6!
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个PageUtil,负责对Page对象进行构造: u=j|']hp#&
java代码: j5hM|\]
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/*Created on 2005-4-14*/ Q2^~^'Yk
package org.flyware.util.page; YA(_*h
e|Ip7`
import org.apache.commons.logging.Log; "F_o%!l
import org.apache.commons.logging.LogFactory; 6@0
wKV!D
1X-Ku GaD
/** }mGOEG|F2
* @author Joa e<_yr>9g"
* JtB"Dh
*/ D@]gc&JN[
publicclass PageUtil { VyRU_<xP
nq'vq]]
privatestaticfinal Log logger = LogFactory.getLog ?gZJ v
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(PageUtil.class); RX]x3-
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/** !: e0cV
* Use the origin page to create a new page dU!`aPL?
* @param page 'vgO`
* @param totalRecords NF?FEUoxz
* @return iQ[0d.(A
*/ 9C$#A +~C
publicstatic Page createPage(Page page, int >;E[XG^
qg7]
YT&
totalRecords){ 79.J`}#
return createPage(page.getEveryPage(), iz|mJUx
w1zI"G~4/Q
page.getCurrentPage(), totalRecords); `i{k^Q
} e"jA#Y #
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/** O5"o/Y~m
* the basic page utils not including exception c[=%v]j:u
.aRL'1xHl
handler U3ygFW%
* @param everyPage OL+!,Y
* @param currentPage apW0(&\
* @param totalRecords |
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* @return page Q:iW k6
*/ 4SG22$7 W
publicstatic Page createPage(int everyPage, int C:tA|<b|
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currentPage, int totalRecords){ eYL7G-3
everyPage = getEveryPage(everyPage); X^3 0a*sj
currentPage = getCurrentPage(currentPage); j/zD`ydj
int beginIndex = getBeginIndex(everyPage, `_2#t1`u
+MQvq\%tG
currentPage); 7f4R5c
int totalPage = getTotalPage(everyPage, +uPN+CgQ@
!'14mN#A
totalRecords); V/5hEo Dt
boolean hasNextPage = hasNextPage(currentPage, h6*=Fn7C
T[$Sbz`
totalPage); {HqwpB\@
boolean hasPrePage = hasPrePage(currentPage); h;vD"!gP
?Az pb}#
returnnew Page(hasPrePage, hasNextPage, (vIrXF5Dnj
everyPage, totalPage, I3Sl>e(Z
currentPage, 1fbd/-h
fgxsC7P$
beginIndex); 4'BzW Z;_a
} `R@24 )
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privatestaticint getEveryPage(int everyPage){ ;F&wGe
return everyPage == 0 ? 10 : everyPage; kO<`RHlX=
} @LY 5]og
~A0E4UJgq
privatestaticint getCurrentPage(int currentPage){ UT[9ERS
return currentPage == 0 ? 1 : currentPage; nf< <]iHf
} TJtW?c7
Q, E!Ew3
privatestaticint getBeginIndex(int everyPage, int `
n{rzenPX
zIbl[[M&
currentPage){ /,v:!*
return(currentPage - 1) * everyPage; :,F^{
} Vvx(7p-GQ
$"{V],:T
|
privatestaticint getTotalPage(int everyPage, int ADX}
l,/q#)5[
totalRecords){ $8&HpX#h$
int totalPage = 0; ,8uu,,c
;U<)$5
if(totalRecords % everyPage == 0) f5a%/1?
totalPage = totalRecords / everyPage; /x_C
else 1at$_\{.(
totalPage = totalRecords / everyPage + 1 ; Fm}O,=
81a&99k#
return totalPage; | -Di/.
} k;3P;@3,W
\3q{E",\>@
privatestaticboolean hasPrePage(int currentPage){ m@JU).NKCS
return currentPage == 1 ? false : true; !W:QLOe6F
} Rn{q/h
v >3ctP{
privatestaticboolean hasNextPage(int currentPage, rOY^w9!
<YL\E v/[
int totalPage){ kyJv,!};
return currentPage == totalPage || totalPage == wrG*1+r
#)R;6"
0 ? false : true; {CH\TmSz
} kt1f2cj
#py7emu
>/n5=RWh
} kSNVI-Wzu
{(wV>Oc>Jw
$!I$*R&
iy
tSC
!W$3p'8Tu
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 K=sQ_j.&Z
|iM*}Ix-
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ?vRz}hiy
Z-4A`@p
做法如下: j~DoMP5Ls
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 RqHxKj
w]yLdfi!
的信息,和一个结果集List: !xo@i XL
java代码: v,>F0ofJ
aic6,>\!'
{>FA ~}cX.
/*Created on 2005-6-13*/ &P3B
package com.adt.bo; 0'97af
=< CH( 4!
import java.util.List; d;#9xD'
Wc3!aLNx
import org.flyware.util.page.Page; RAE|eTnna
Q X@&~
/** j{_MDE7N
* @author Joa M/V
>25`
*/ !+)$;`
publicclass Result { `*oLEXYN
n^Z?u9VR
private Page page; ;8
McG83
PLLlo~Bb
private List content; >4EcV1y
|P?8<8p
/** wuYo@DDU#
* The default constructor q/OraPAB
*/ 6C]!>i}U
public Result(){ OD1ns
super(); r)j#Skh].
} R:.7c(s
^\+6*YE 4
/** I:6xDDpZG`
* The constructor using fields ;
wHuL\
* [ z$J
* @param page La9@h"
* @param content 3al5Vu2:
*/ j|aT`UH03
public Result(Page page, List content){ E"G._<3J8
this.page = page; ?tA-`\E
this.content = content; G~esSL^G/
} J"83S*2(j
0_] aF8j
/** +V'r>C:
* @return Returns the content. },Z-w_H
*/ BK /;HG
publicList getContent(){ v>R.M"f
return content; Ej34^*m9k
} a|s= d
[\.>BK
/** gdG:
&{|x
* @return Returns the page. ))KsQJ"V
*/ Z#J{tXZc
public Page getPage(){ 'xi..
return page; '6WDs]\
} Ck^= H
1$Hf`h2
/** (u'/tNGS
* @param content s+CXKb +
* The content to set. LB{a&I LG
*/ 8 Zj>|u
public void setContent(List content){ 73<iK]*c
this.content = content; qJ!oH&/cD
} e5XikLu
[&`>&u@MK
/** ah<f&2f
* @param page r2Z`4tN:
* The page to set. {
o;0Fx
*/ ih;TQ!c+b
publicvoid setPage(Page page){ x)U;
this.page = page; *xjIl<`pK
} ~Igo
8ykl
} RI*%\~6t?
rFK
*
C4cg,>P7
=lmh^**4
P<(mH=K
2. 编写业务逻辑接口,并实现它(UserManager, QA 9vH'
0ND7F
UserManagerImpl) O0l;Qi
java代码: ixH7oWH#
c]&VUWQ
W2B=%`sC
/*Created on 2005-7-15*/ *Xnq1_K}
package com.adt.service; ?-Z:N`YP
^R$dG[Qf
import net.sf.hibernate.HibernateException; DtN6.9H2`
h
,n!x:zy@
import org.flyware.util.page.Page; ~VGK#'X:
Cwh;+3?C|
import com.adt.bo.Result; gjWH
}(K
a[!d)Y:zx
/** ;7A,'y4f
* @author Joa "O
'I
*/ ;C<A}
publicinterface UserManager { SYwNx">Bq
O^$Zz<
public Result listUser(Page page)throws gc:>HX);)
c8s/`esA
HibernateException; qs b4@jt+
>dGYZfqD
} j%h
Y0
.0ZvCv:>
qprOxP
r
8UcT?Zp
{ULnQ6@
java代码: Fo=6A[J
ZM.g+-9
f$'D2o, O
/*Created on 2005-7-15*/ Y|~>(
package com.adt.service.impl; [)u(\nfGX
F{+`F<r
import java.util.List; OR9){qP
c 1GP3
import net.sf.hibernate.HibernateException; f5-={lUlIS
FHC7\#p/9Z
import org.flyware.util.page.Page; E=QQZ\w
import org.flyware.util.page.PageUtil; (Vv]:Y]
Ei<:=6EX?8
import com.adt.bo.Result; eH8.O
import com.adt.dao.UserDAO; jYF3u0
)
import com.adt.exception.ObjectNotFoundException; 5=986ci$U
import com.adt.service.UserManager; `y#C%9#
Qa%SvA@R
/** (jG$M= q-
* @author Joa jayoARUB
*/ :<gk~3\
publicclass UserManagerImpl implements UserManager { GZt] 38V)g
Jx<
private UserDAO userDAO; -tdG}Gu
)]R?v,9*D
/** tK
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* @param userDAO The userDAO to set. Zv\b`Cf}
*/ WGx>{'LJ
publicvoid setUserDAO(UserDAO userDAO){ #w@Pa L iS
this.userDAO = userDAO; aB)DX
} Z(eSnV_RL
U*TN/6Qy.
/* (non-Javadoc) ~4<3`l=A
* @see com.adt.service.UserManager#listUser sCl,]g0{
IycxRig
(org.flyware.util.page.Page) QR'g*Bro
*/ kDh(~nfj
public Result listUser(Page page)throws +GS=zNw#
;gnr\C*G
HibernateException, ObjectNotFoundException { 5aNDW'z`f
int totalRecords = userDAO.getUserCount(); lg+g:o
if(totalRecords == 0) Sq,ty{j2%
throw new ObjectNotFoundException 4vS!99v)
>6 #\1/RP
("userNotExist"); ]Dg0@Y
page = PageUtil.createPage(page, totalRecords); bn35f<+
List users = userDAO.getUserByPage(page); O;BPd:<
returnnew Result(page, users); Gf\_WNrSE+
} $O8V!R*
<UdD@(iZ#
} ~S!kn1&O
&:*+p-!2<
%#a%Luq
GcCs}(eo
_'U?!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 E;H(jVZ
dCTpO
询,接下来编写UserDAO的代码: P0z{R[KBH
3. UserDAO 和 UserDAOImpl: =[+&({
java代码: OvG0UXRU
*,*qv^
E5{)d~q
/*Created on 2005-7-15*/ z]AS@}wWqg
package com.adt.dao; @\8gzvkt
A#:
c
import java.util.List; Uc0'XPo3I
="R6YL
import org.flyware.util.page.Page; Z-a(3&
yZ$;O0f&&
import net.sf.hibernate.HibernateException; ?/MXcI(
-%l,Zd9
/** Yj\yO(o/
* @author Joa |l(lrJ{
*/ B31-<w
publicinterface UserDAO extends BaseDAO { KBe {
!
hr@{CD
publicList getUserByName(String name)throws
(Nb1R"J`
>L`mF_WG
HibernateException; x{V>(d'p
|7x^@i9w
publicint getUserCount()throws HibernateException; [frD
L)
R} 9jgB
publicList getUserByPage(Page page)throws KB*=a
EsB'nf r
HibernateException; 2(//slP
F|`B2Gr
} [#'_@zZz
NV4W2thYo
>%dAqYi $
ibs"Iv34
no6]{qn=6
java代码: F)kLlsp
<9tG_
vXQmEIm
/*Created on 2005-7-15*/ <#
r.}T.l
package com.adt.dao.impl; H)aC'M^
@zF:{=+]+
import java.util.List; u!k<sd_8B
=w$"wzc
import org.flyware.util.page.Page; TbAdTmW
HCkqh4
import net.sf.hibernate.HibernateException; $!!=fFX*y
import net.sf.hibernate.Query; *"{Z?< 3
\1C!,C
import com.adt.dao.UserDAO; bk9~63tN+>
.hNw1~Fj
/**
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* @author Joa !&jgcw/E
*/ jI<WzvhYG
public class UserDAOImpl extends BaseDAOHibernateImpl W(lKR_pF
oe|<xWu
implements UserDAO { qgsE7 ]
"d>g)rvOc
/* (non-Javadoc) DLVs>?Y
* @see com.adt.dao.UserDAO#getUserByName [HiTR !o*
<?7,`P:h[
(java.lang.String) ||ZufFO
*/ XfK.Fj~-
publicList getUserByName(String name)throws *Q120R
,bp pM
HibernateException { Xb:BIp!e
String querySentence = "FROM user in class u4M2Ec
C{i;spc!bi
com.adt.po.User WHERE user.name=:name"; #]a51Vss
Query query = getSession().createQuery &~A*(+S
maEpT43f
(querySentence); +Z~!n
query.setParameter("name", name); `$agM@"^
return query.list(); $RNUr
\9A
} a{Hb7&
IetGg{h.
/* (non-Javadoc) %R*vSRG/U
* @see com.adt.dao.UserDAO#getUserCount() 9Y@?xn.\
*/ lF"(|n"R
publicint getUserCount()throws HibernateException { ~nc([%!=
int count = 0; )'dH}3Ba
String querySentence = "SELECT count(*) FROM -Dq:Y,%q
q;0&idYC
user in class com.adt.po.User"; 9f%y)[ \
Query query = getSession().createQuery O0(Q0Ko
F@'rP++4
(querySentence); RHl=$Hm.%
count = ((Integer)query.iterate().next v;}`?@G
[x p,&
()).intValue(); FO>( QLlH
return count; mS~ ]I$
} UK_aqB
"zIq)PY
/* (non-Javadoc) D62
NU
* @see com.adt.dao.UserDAO#getUserByPage <6O_t,K]
>aC\_Mc
(org.flyware.util.page.Page) ZWhmO=b!
*/ tvH\iS #V
publicList getUserByPage(Page page)throws D<3V#Opw
xm,`4WdG
HibernateException { V;hwAQbF
String querySentence = "FROM user in class [H:GKhPC`
sqpOS!]
com.adt.po.User"; , 64t
Query query = getSession().createQuery ]baaOD$Z
]F*a PV
(querySentence); m_Ac/ctf
query.setFirstResult(page.getBeginIndex()) Ao,!z
.setMaxResults(page.getEveryPage()); O][Nl^dl
return query.list(); Li-(p"
} C| L^Ds0
$7DcQ b9
} 11y.z^
5+/b$mHZX
kAB+28A
d:<H?~
MjXE|3&
至此,一个完整的分页程序完成。前台的只需要调用 hN_f h J
Am4^v?q
userManager.listUser(page)即可得到一个Page对象和结果集对象 ,WB_C\.#XN
Z-h7
的综合体,而传入的参数page对象则可以由前台传入,如果用 +5t
bK
Ds%&Mi
webwork,甚至可以直接在配置文件中指定。 sId(PT^
uQu/(5
下面给出一个webwork调用示例: >g>`!Sf
java代码: E_D ^O
]dbSa1?
~@4ZV
/*Created on 2005-6-17*/ 6%\Q*r*N
package com.adt.action.user; l/png:
T<f\*1~^
import java.util.List; Z 5)_B,E:X
,c%K)KuPK.
import org.apache.commons.logging.Log; 9sU+IT K4
import org.apache.commons.logging.LogFactory; pgd8`$(Q
import org.flyware.util.page.Page; ;w6fM
Gl8&FrR
import com.adt.bo.Result; O%JsUKV
import com.adt.service.UserService; 3 IWLBc
import com.opensymphony.xwork.Action; '-PMF~~S
Vp]D
/** "rx^M*"
* @author Joa ^K.u
~p
*/ phgexAq
publicclass ListUser implementsAction{ 6vgBqn[
8@%mnyQ
privatestaticfinal Log logger = LogFactory.getLog N=T.l*8
EY)Gi`lK
(ListUser.class); a%T -Z.rd
EzIs@}
private UserService userService; 2T@L{ ql
1 O7]3&L@
private Page page; 0Ws;|Yg
;;?vgrz
privateList users; ```d:f
1X::0;3
/* 7k]RO
* (non-Javadoc) ?AnjD8i
* 2<'`^AO@
* @see com.opensymphony.xwork.Action#execute() e`Co,>W/
*/ ?jri!]ux#
publicString execute()throwsException{ *!g 24
Result result = userService.listUser(page); ;Rhb@]X
page = result.getPage(); ms}f>f=
users = result.getContent(); @GG(7r\/B
return SUCCESS; V \6(d
} <8rgtu!VU
G`,u40a
/** h@~:(:zU$
* @return Returns the page. Il{^
j6
*/ [6; N3?+
public Page getPage(){ 69C8-fF0[I
return page; ]^:hyOK
} Re*|$r#
,\o<y|+`S
/** dU]i-NF
* @return Returns the users. K DYYB6|
*/ wfxOx$]zK
publicList getUsers(){ 4l&"]9D
return users; gEv-> pc
} =n-z;/NL
ohrw\<xsu
/** g4:VR:o
* @param page %5JW<9
* The page to set. -B1YZ/.rz"
*/ co5y"yj_
publicvoid setPage(Page page){ xfq]9<
this.page = page; F#(.v7Za
} z,{e]MB)M
N5nvL)a~
/** >dpbCPJ9[
* @param users y(bsCsV&
* The users to set. yjEI/9_
*/ $ph0ag+
publicvoid setUsers(List users){ [kbC'Eh*
this.users = users; -IBO5;2_
} x*.Ye5Jb
}B y)y;~
/** 3{N\A5~
* @param userService c 9rVgLqn!
* The userService to set. F=XF]
*/ ]7a;jNQu
publicvoid setUserService(UserService userService){ [6D>f?z
this.userService = userService; FU%~9NKX
} I4)Nb WQ
} ?75\>NiR
Dp*:Q){>E
)ll?-FZ
T yU&QXb
* R%.a^R
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, &Hv;<
AD^X(rW
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 x6LjcRS|
KNy`Lj)VPY
么只需要: Hu[]h]
java代码: 3bWum
RfKc{V
`f@{Vcr%i
<?xml version="1.0"?> %drJ p6n%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ibvJWg
'/k^C9~m
r
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Bg-VCJI<
a`#S|'oatC
1.0.dtd"> 0pD
W _
JwZ?hc
<xwork> TfJL+a0
kLJlS,nh\r
<package name="user" extends="webwork- EYG"49
c
TMK'(6dH
interceptors"> yI8 SQ$w0y
=f>HiF
<!-- The default interceptor stack name B={/nC}G~
kl"
]Nw'C
--> W9dYljnZ8i
<default-interceptor-ref q69H^E=
Q uB+vL
name="myDefaultWebStack"/> yz?q(]
@rF/]UJ
<action name="listUser" MEEAQd<*
RcQ>eZHl
class="com.adt.action.user.ListUser"> Jy9bY
<param !2z!8kI
l]H0g[
name="page.everyPage">10</param> 0 h22V$
<result QZ&4:K+{
YgEM:'1f
name="success">/user/user_list.jsp</result> +@0TMK,P
</action> yO=p3PV d
<;%0T
xK|U
</package> E/ijvuO
\<ZLoy_
</xwork> S_2"7
{7qA &c=
|Ab{H%
P.cO6+jGR
j eq:
RX'-99M
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 w:}C8WKw
[(|^O>k8c
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。 qIh #~
GB>aT-G7q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Gg|M+M?+
7:TO\0]2n
B oqJ
'<7S^^ax
O}C)~GU
我写的一个用于分页的类,用了泛型了,hoho ,^ 7 CP
zie=2
java代码: ,)zt
AFn=
2U}m RgJu
'.Z4 hHX
package com.intokr.util; ^;r+W-MQ
\5~;MI.Sq
import java.util.List; $o.Kn9\
FQROK4x%"
/** o2aM#Q
* 用于分页的类<br> 94Ud@F9d5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> `XW*kxpm
* KXf<$\+zO
* @version 0.01 ^O)ve^P
* @author cheng JB^Q\;$
*/ $w)~xE5;
public class Paginator<E> { WS:5MI,OL
privateint count = 0; // 总记录数 W`rMtzL5
privateint p = 1; // 页编号 ^,TTwLy-t
privateint num = 20; // 每页的记录数 R-
privateList<E> results = null; // 结果 =1Z;Ma<;
+{$QAjW(/
/** \3zp)J
* 结果总数 rQJ"&CapT
*/ 8gC)5Y
publicint getCount(){ Hm
fXe
return count; wzh]97b
} >.<ooWw
YTQps&mD.
publicvoid setCount(int count){ J -V49X#
this.count = count; _6MdF<Xb/
} B[F-gq-
ka/XK[/'
/** ``u:lL
* 本结果所在的页码,从1开始 Gr: 3{o`
* !8R@@,_v
* @return Returns the pageNo. nNaXp*J
*/ RV+E^pkp$
publicint getP(){ u1Ek y/e-
return p; U>P|X=)
} \4{2eU
qaVy.
/** gg^1b77hT
* if(p<=0) p=1 !VP %v&jKm
* !tXZ%BP.u
* @param p f:wd&V
*/ c0ez/q1S
publicvoid setP(int p){ v+=k-;-
if(p <= 0) e;VIL 2|
p = 1; Kesy2mE
this.p = p; s+Q;pRZW{
} " xR[mJ@U
1ibnx2^YB
/** <7XT\?%F
* 每页记录数量 ,*Z.
*/ HjA_g0u
publicint getNum(){ (qBvoLkF9N
return num; ys'T~Cs
} @hif$
v,OpTu:1
/** u6Je@e_!
* if(num<1) num=1 --fFpM3EvS
*/ 1J}8sG2`
publicvoid setNum(int num){ y(a!YicA?
if(num < 1) eV7u*d?
num = 1; U#
JIs
this.num = num; wO.iKX;
} Q@-ovuxi
` ;)ZGY\
/** o.7{O,v
* 获得总页数 {gsdG-
*/ h}L}[
publicint getPageNum(){ fuX'~$b.fA
return(count - 1) / num + 1; bZ 443SG
} nSx]QREL!
Paj vb-f
/** r~7:daG*
* 获得本页的开始编号,为 (p-1)*num+1 :I1_X
*/ \or G63T:
publicint getStart(){ .*YD&(
return(p - 1) * num + 1; PRB{VC<k
} wy,p&g)>
)ev<7g9*q
/** )]43R
* @return Returns the results. g(ogXA1
*/ v [njdP
publicList<E> getResults(){ e]Fp=*#
return results; Sr_VL:Gg
} dy>!KO
-JT/9IQ
public void setResults(List<E> results){ 'h1b1,b~
this.results = results; Uf\nFB? ^
} XfYC7-e9c
j&R+2%
public String toString(){ ArK]0$T
StringBuilder buff = new StringBuilder I?Aj.{{$G%
9QC.TG@
(); -&2B@]]
buff.append("{"); sOU_j:A80;
buff.append("count:").append(count); uz30_aH
buff.append(",p:").append(p); sEc;!L
buff.append(",nump:").append(num); %~xGkk"I
buff.append(",results:").append As&vFt P
++-{]wB3=.
(results);
#^#HuDH
buff.append("}"); S9| a$3K'
return buff.toString(); 6Jz^
} 9uk<&nqx
I5m][~6.?
} ~b~2
>c9
*^%*o?M~
13hE}g;.