Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Yfk){1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 9I a4PPEH1
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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 ~zklrBn&
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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 >H@
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分页支持类: }lzyl*.
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java代码: ;79X#hI
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package com.javaeye.common.util; x%ZgLvdp,
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import java.util.List; "_qH+=_R
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publicclass PaginationSupport { mPNT*pAO
p @@TOS
publicfinalstaticint PAGESIZE = 30; q$EicH}k8
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privateint pageSize = PAGESIZE; P8K{K:T
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privateList items; n*6 b*fl
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privateint totalCount; 4@PH5z
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privateint[] indexes = newint[0]; hKw4 [wB]
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privateint startIndex = 0; t\nYUL-H
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public PaginationSupport(List items, int <d,Qi.G4
@U6Iw"@
totalCount){ *<n]"-
setPageSize(PAGESIZE); WJ$D]7
setTotalCount(totalCount); vn@9Sqk
setItems(items); 1u&}Lq(
setStartIndex(0); gF;i3OJg
} K!6k<
u1F@VV{
public PaginationSupport(List items, int Xc;W9e(U
)J4XM(
totalCount, int startIndex){ RiC1lCE
setPageSize(PAGESIZE); 8KRm>-H)
setTotalCount(totalCount); 4QODuyl2H
setItems(items); XTpYf
setStartIndex(startIndex); ;^nN!KDjR
} s^F6sXhyPi
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public PaginationSupport(List items, int [k-Q89
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totalCount, int pageSize, int startIndex){ @l:\0cO
setPageSize(pageSize); =n>&Bl-Bl
setTotalCount(totalCount); <U(wLG'XS
setItems(items); m[6?v;w
setStartIndex(startIndex); 3B#qQ#
} lB9 9J"A
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publicList getItems(){ 33dHTV
return items; wlk{V
} $'FPsoH
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publicvoid setItems(List items){ {%W'Zx
this.items = items; !5lb+%7
} H&`0I$8m
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publicint getPageSize(){ |P!7T.
return pageSize; yClX!OL
} .}
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; [\eh$r\
} _p0@1 s(U
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publicint getTotalCount(){ (JV [7u -
return totalCount; 1.29%O8V_
} u7 s-
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publicvoid setTotalCount(int totalCount){ WbF[4x
if(totalCount > 0){
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this.totalCount = totalCount; ?r
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int count = totalCount / t!^ j0 q
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pageSize; 2>`m1q:
if(totalCount % pageSize > 0) )wT@`p"4
count++; z)AZ:^!O
indexes = newint[count]; \N3A2L)l
for(int i = 0; i < count; i++){ E~]37!,\\9
indexes = pageSize * _#;UXAi
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i; s>pM+PoGYd
} hB[VU
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}else{ ylTX
this.totalCount = 0; Xg<R+o
} .|?UqZ(,
} yyZs[5Q
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publicint[] getIndexes(){ 85e!)I_
return indexes; WR:I2-1
} "+dByaY
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publicvoid setIndexes(int[] indexes){ U 7_1R0h
this.indexes = indexes; b+/z,c6w
} 1\u{1
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publicint getStartIndex(){ eVRPjVzQ'Q
return startIndex; ov$S
} z79c30y]"
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publicvoid setStartIndex(int startIndex){ ORDVyb_x
if(totalCount <= 0) F-TDS<[S?
this.startIndex = 0; Od]B;&F
elseif(startIndex >= totalCount) l$:?82{
this.startIndex = indexes UlD]!5NO
wdMVy=SS
[indexes.length - 1]; v$d^>+Y#
elseif(startIndex < 0) k1_"}B5
this.startIndex = 0; eeM$c`Y<
else{ E{8-VmY
this.startIndex = indexes x\K9|_!
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[startIndex / pageSize]; D/oO@;`'c
} 1e)5D& njS
} ]_js-+w6
@AfC$T
publicint getNextIndex(){ &6O0h0Vy
int nextIndex = getStartIndex() + "lnI@t{o
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pageSize; d`sIgll&n
if(nextIndex >= totalCount) @.8FVF
return getStartIndex(); (yO8G-Z0
else 2qDyb]9
return nextIndex; :=oIvSnh
} Sau?Y
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publicint getPreviousIndex(){ ;y]BXW&l&
int previousIndex = getStartIndex() - )u>/:
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pageSize; h
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if(previousIndex < 0) 7*C>4Gs
return0; <7*d2
else /#Lm)-%G
return previousIndex; ^X|Bzz)
} *T-v^ndJh
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} `7
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抽象业务类 Ocf :73t
java代码: m~R Me9Qi
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/** WVdF/H
* Created on 2005-7-12 @,;VMO
*/ Jk_}y
package com.javaeye.common.business; ueLdjASJ
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import java.io.Serializable; ^+u/Lw&
import java.util.List; _qjkiKm?1F
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import org.hibernate.Criteria; wj-z;YCV
import org.hibernate.HibernateException; Q+zy\T
import org.hibernate.Session; yv2wQ_({
import org.hibernate.criterion.DetachedCriteria; !Nx'4N`&l
import org.hibernate.criterion.Projections; <>R\lPI2
import }]+k
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org.springframework.orm.hibernate3.HibernateCallback; ;{Tf:j'g
import ]?UK98uS\A
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org.springframework.orm.hibernate3.support.HibernateDaoS \PM5B"MDZ
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upport; qV:TuR-|w
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import com.javaeye.common.util.PaginationSupport; iE* Y@E5x0
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public abstract class AbstractManager extends w~Jy,[@n
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HibernateDaoSupport { W7?f_E\>W
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privateboolean cacheQueries = false; ;[! W*8.c
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privateString queryCacheRegion; i1DJ0xC]
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publicvoid setCacheQueries(boolean /<)kI(gf
9
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cacheQueries){ )|IMhB+4
this.cacheQueries = cacheQueries; ]C5/-J,F
} z0xw0M+X
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publicvoid setQueryCacheRegion(String lvk
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queryCacheRegion){ t+2,;G
this.queryCacheRegion = 2sYOO>
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queryCacheRegion; 7cly{U"
} ["SD'
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publicvoid save(finalObject entity){ +=g9T`YbE
getHibernateTemplate().save(entity); /..a9x{At>
} xL}~R7
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publicvoid persist(finalObject entity){ .Uh|V-
getHibernateTemplate().save(entity); Gu5%P ou
} fSw6nEXn
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publicvoid update(finalObject entity){ o 12wp
getHibernateTemplate().update(entity); Y(Q!OeC
}
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publicvoid delete(finalObject entity){ DY?;Z98P?
getHibernateTemplate().delete(entity); -/gAb<=
} :Kx6|83
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publicObject load(finalClass entity, {p)=#Jd`.P
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finalSerializable id){ ]n (:X
return getHibernateTemplate().load bYB:Fe=2
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(entity, id); IM*T+iRKqF
} `cn}}1Lg]
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publicObject get(finalClass entity, k!=
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finalSerializable id){ 3{R7y
return getHibernateTemplate().get EViQB.3w\
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(entity, id); k(%h{0'
} VMgO1-F
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publicList findAll(finalClass entity){ VVVw\|JB>
return getHibernateTemplate().find("from \*.u(8~2o
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" + entity.getName()); a+#Aitd
} *7:HO{P>Y
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publicList findByNamedQuery(finalString 8zWKKcf7t
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namedQuery){ `8<h aU
return getHibernateTemplate G'0]m-)dw
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().findByNamedQuery(namedQuery); [lbe_G;
} z*BGaSX %
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publicList findByNamedQuery(finalString query, SXx;-Ws
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finalObject parameter){ \Czuf
return getHibernateTemplate ;"j>k>tg
G$_=rHt_%
().findByNamedQuery(query, parameter); l
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} /By`FW Y
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publicList findByNamedQuery(finalString query, jZLD^@AP
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finalObject[] parameters){ _q/UDf1
return getHibernateTemplate UYW{AG2C
"? t@Y
().findByNamedQuery(query, parameters); s%p,cz;
,
} B9(e"cMm
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publicList find(finalString query){ *&A/0]w
return getHibernateTemplate().find 0b~{l;
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(query); D^jyG6Ch
} <sNkyQ
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publicList find(finalString query, finalObject 5^ +QTQ
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parameter){ j\9v1O!T
return getHibernateTemplate().find rW<sQ0
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(query, parameter); O!=ae|
} ?O!'ZZX
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public PaginationSupport findPageByCriteria JZM:R
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(final DetachedCriteria detachedCriteria){ 4EtP|
return findPageByCriteria Pk6l*+"r<
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); M^twD*
} WUnmUW[/
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public PaginationSupport findPageByCriteria 8p)*;Y
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(final DetachedCriteria detachedCriteria, finalint }q~M$
*#n?6KqZ
startIndex){ 8H})Dq%d 7
return findPageByCriteria eJv_`#R&Of
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(detachedCriteria, PaginationSupport.PAGESIZE, ?-g/hXx;
4?3*%_bDJ,
startIndex); W@(EEMhw
} "\]NOA*
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public PaginationSupport findPageByCriteria Gj%cU@2
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(final DetachedCriteria detachedCriteria, finalint 7@@,4_q E
)`sEdVxbr
pageSize, i{9_C/
finalint startIndex){ |*w}bT(PfR
return(PaginationSupport) uR:@7n
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getHibernateTemplate().execute(new HibernateCallback(){ bZB7t`C5
publicObject doInHibernate 9O.okU
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(Session session)throws HibernateException { G; *jL4
Criteria criteria = rh6gB]X]3:
rv\yS:2
detachedCriteria.getExecutableCriteria(session); %FDv6peH
int totalCount = Hlr[x
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((Integer) criteria.setProjection(Projections.rowCount 2;z~xR
zP8a=Iv
()).uniqueResult()).intValue(); M!9gOAQP
criteria.setProjection /g_cz&luR
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(null); B3j
List items = [f?fA[,[
r ^m8kYezQ
criteria.setFirstResult(startIndex).setMaxResults |\lsTY&2
l.
9
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(pageSize).list(); ;9+[t8Y)D
PaginationSupport ps = M_+"RKp
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new PaginationSupport(items, totalCount, pageSize, 4DYa~ =w
)H'SU_YU
startIndex); .]0u#fz0y
return ps; iE~][_%U
} c,K)*HB
}, true); C3XB'CL6
} sUCI+)cM3
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public List findAllByCriteria(final ZCT\4Llv#
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DetachedCriteria detachedCriteria){ 9ff6Apill
return(List) getHibernateTemplate !R;NV|.eI6
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().execute(new HibernateCallback(){ g[NmVY-o
publicObject doInHibernate / bxu{|.
klwC.=?(j"
(Session session)throws HibernateException { 4P406,T]r
Criteria criteria = Q|DVB
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detachedCriteria.getExecutableCriteria(session); F1Jd-3ei
return criteria.list(); 9_h
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} _uYidtxo=
}, true); z!M8lpIM
} K4G43P5q`
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public int getCountByCriteria(final .J0Tn,m
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DetachedCriteria detachedCriteria){ !R 2;]d*
Integer count = (Integer) >l0y
ss)I
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getHibernateTemplate().execute(new HibernateCallback(){ nQtp 4
publicObject doInHibernate ^n @dC?
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(Session session)throws HibernateException { >!U oS
Criteria criteria = LA837P
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detachedCriteria.getExecutableCriteria(session); .Wr%l$~
return I1a>w=x!+
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criteria.setProjection(Projections.rowCount mB.j?@Y%
$ #*";b)QY
()).uniqueResult(); 7xhBdi[ dQ
} o#^(mGj_.
}, true); RCL}bE
return count.intValue(); |h7 d#V>
} B%.vEk)*
} =^9I)JW
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用户在web层构造查询条件detachedCriteria,和可选的 B&M-em=
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 s2X<b
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PaginationSupport的实例ps。 \se
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ps.getItems()得到已分页好的结果集 I&Z4?K
ps.getIndexes()得到分页索引的数组 @~+W
ps.getTotalCount()得到总结果数 :f/T$fa*
ps.getStartIndex()当前分页索引 7:S4 Ur
ps.getNextIndex()下一页索引 0# d:<+4D
ps.getPreviousIndex()上一页索引 "G[yV>pxv
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n90DS/Yx
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 s$wIL//=
u= =`]\_@
一下代码重构了。 a`*Dq"9pV
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我把原本我的做法也提供出来供大家讨论吧: O,[9E
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首先,为了实现分页查询,我封装了一个Page类: Pea2ENe3
java代码: U ID0|+%Y
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/*Created on 2005-4-14*/ ]I[\Io 1
package org.flyware.util.page; G&z^AV
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/** ) -^(Su(!
* @author Joa d2U+%%Tdw
* \n>7T*iM&
*/ eq6>C7.$
publicclass Page { r T"3^,,
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/** imply if the page has previous page */ Ow50M;E
privateboolean hasPrePage; rX}FhBl5
(&!RX.i
/** imply if the page has next page */ ^5n#hSqZ=M
privateboolean hasNextPage; 2)MX<prH
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/** the number of every page */ &hcD/*_Z
privateint everyPage; 7ND4Booul
ZKTY1JW_
/** the total page number */ M3VTzwuf^S
privateint totalPage; I|<`Er-;58
p|>m 2(|
/** the number of current page */ HV=P!v6
privateint currentPage; &d_2WQ}
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/** the begin index of the records by the current $U4[a:
6&;h+;h
query */ #H]c/
privateint beginIndex; `O]$FpO
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/** The default constructor */ INEE
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public Page(){ Z]XjN@j"
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} %)w7t[A2D
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/** construct the page by everyPage R0urt
* @param everyPage 73l,PJ
* */ XzBlT( `w
public Page(int everyPage){ Vy6~O|68=
this.everyPage = everyPage; 88VI
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} ?_d3|]N
x~ID[
/** The whole constructor */ ]sI\.a
public Page(boolean hasPrePage, boolean hasNextPage, SB`xr!~A]
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j8+>E?nm
int everyPage, int totalPage, JfRLqA/
int currentPage, int beginIndex){ kP1cwmZ7F
this.hasPrePage = hasPrePage; KB{IWu
this.hasNextPage = hasNextPage; C@g/{?\
this.everyPage = everyPage; X/Ii}X/p
this.totalPage = totalPage; 11%Zx3
this.currentPage = currentPage; &79F
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this.beginIndex = beginIndex; h0C>z2iH
} /m4Y87
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/** p^w_-(p
* @return e?N3&ezp
* Returns the beginIndex. S0ReT*I
*/ o7^0Lo5Z?
publicint getBeginIndex(){ lQv(5hIm
return beginIndex; TAq[g|N-;
} /4}y2JVv)
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/** tF\_AvL_8
* @param beginIndex %~M#3Ywa
* The beginIndex to set. c<sq0('`
*/ >>cL"m
publicvoid setBeginIndex(int beginIndex){ 2cwJ);Eg2
this.beginIndex = beginIndex; iba8G]2
} ^V7)V)Z;0
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/** RY1-Zjlb<
* @return 0<##8m@F8
* Returns the currentPage. !%B-y9\
*/ 24sQon
publicint getCurrentPage(){ s<oT,SPt
return currentPage; t>x!CNb'C
} e7tio!
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/** ..w$p-1
* @param currentPage h>p,r\X
* The currentPage to set. x3F94+<n{
*/ phB d+zQc
publicvoid setCurrentPage(int currentPage){ FEX67A8/;
this.currentPage = currentPage; (j(9'DjP
} y'n<oSB}
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/** g4{0
* @return +{}p(9w@
* Returns the everyPage. [z6P]eC7
*/ P@x@5uC2
publicint getEveryPage(){ T5}5uk9
return everyPage; ,Ek6X)|@
} %IDl+_j
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/** yo$A0Ti!w
* @param everyPage {hm-0Q
* The everyPage to set. 88 ca
*/ }=.C~f]A
publicvoid setEveryPage(int everyPage){ uaxkGEXr
this.everyPage = everyPage; ,dFY]
} 9>ZX@1]m_
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/** +ZV?yR2yn
* @return 2z1r|?l
* Returns the hasNextPage. gKgdu($NJ
*/ ;=@?( n
publicboolean getHasNextPage(){ 4{b/Nv:b
return hasNextPage; l1%*LyD
} @&9<)1F
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/** . TNJuuO
* @param hasNextPage pBn;:
* The hasNextPage to set. :K(+ KN(
*/ k9c`[M
publicvoid setHasNextPage(boolean hasNextPage){ D2io3Lo$ov
this.hasNextPage = hasNextPage; G {a;s-OA3
} +!G)N~o
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/** (: mF+%(
* @return WckWX]};S
* Returns the hasPrePage. fvG4K(
*/ Qr?(2t#
publicboolean getHasPrePage(){ ;:bnLSPo
return hasPrePage; P_gai7Xg
} *P`k |-
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/** T'N/A9{q
* @param hasPrePage j"&Oa&SH
* The hasPrePage to set. 8{Vt8>4
*/ T\Jm=+]c!
publicvoid setHasPrePage(boolean hasPrePage){ ^n\g,
this.hasPrePage = hasPrePage; YCyh+%Q(
} +.X3&|@k
!ed0
/** CR-2>,*a9
* @return Returns the totalPage. \u 6/nvZ]N
* ;Udx|1o
*/ t\\<+^[%
publicint getTotalPage(){ ,4(m.P10
return totalPage; SqoO"(1x
} U^OR\=G^
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/** Lvn+EM
* @param totalPage D]K?ntS[*
* The totalPage to set. a!;K+wL
>
*/ z>spRl,dr
publicvoid setTotalPage(int totalPage){ UR[UZ4G
this.totalPage = totalPage; }`uq:y
} t>"|~T$9
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} 4& 9V
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szy2"~hm
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 smuQ1.b
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个PageUtil,负责对Page对象进行构造: M =GF@C;b
java代码: N!13QI
H
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/*Created on 2005-4-14*/ +kOXa^K
package org.flyware.util.page; +<c(;Ucl?
a.SxMF
import org.apache.commons.logging.Log; oF5~|&C
import org.apache.commons.logging.LogFactory; }yM!o`90
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/** f`p"uLNo<
* @author Joa '6Yx03t
* NQ\<~a`Eq
*/ 7]8apei|
publicclass PageUtil { E)(Rhvij
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privatestaticfinal Log logger = LogFactory.getLog DbK-3F_
r1|;V~a$~
(PageUtil.class); [u/W h+
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/** f15n ~d
* Use the origin page to create a new page :-1
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* @param page CrEC@5j
* @param totalRecords Bfr$&?j#
* @return o$,e#q)8
*/ 6zW3!_tz
publicstatic Page createPage(Page page, int }%k3
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totalRecords){ LT)G"U~
return createPage(page.getEveryPage(), ~_"/\;1
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page.getCurrentPage(), totalRecords); P}mn2Hs
} 9Zpd=m8dU
UWq[K&vQZ
/** %8T"h
* the basic page utils not including exception +[$ Q C*
f;%\4TH?
handler ffS]%qa
* @param everyPage Fs;_z9ej-u
* @param currentPage / FA0(< -}
* @param totalRecords ER*Et+>
* @return page S%k](\7!
*/ zsha/:b
publicstatic Page createPage(int everyPage, int *9xv0hRQ%?
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currentPage, int totalRecords){ ".T&nS[z
everyPage = getEveryPage(everyPage); tJ!s/|u(
currentPage = getCurrentPage(currentPage); B]|"ePj-
int beginIndex = getBeginIndex(everyPage, C.oC@P
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currentPage); V.Ki$0>
int totalPage = getTotalPage(everyPage, &Ew{ {t;"
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totalRecords); LHJjPf)F
boolean hasNextPage = hasNextPage(currentPage, Kn+m9
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totalPage); *FrlzIAom
boolean hasPrePage = hasPrePage(currentPage); S,~DA3
h#!u"'JW
returnnew Page(hasPrePage, hasNextPage, rkz_h
everyPage, totalPage, E||[(l,b
currentPage, NRgNW1#
]K(>r#'nH
beginIndex); [exIK
} szx7CP`<8
L+o"<LV]
privatestaticint getEveryPage(int everyPage){ ]5}C@W@_
return everyPage == 0 ? 10 : everyPage; x O~t
} \$]
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}^np
privatestaticint getCurrentPage(int currentPage){ r|>a;nY
return currentPage == 0 ? 1 : currentPage; 1^4z/<ZWm
} 8V$ :th('
( d2|r)O
privatestaticint getBeginIndex(int everyPage, int Ow\dk^\-G8
Rg!Fu
currentPage){ "\9!9U#!
return(currentPage - 1) * everyPage; R|Lr@k{6+r
} [spJ%AhV
@GpM4>:
privatestaticint getTotalPage(int everyPage, int s;'jn_,0
8(EK17rE`
totalRecords){ ,@1.&!F4it
int totalPage = 0; W+C@(}pt
LK1 r@
if(totalRecords % everyPage == 0) "
tUS>c/
totalPage = totalRecords / everyPage; A1A/OU<Vb
else |%@.@c
totalPage = totalRecords / everyPage + 1 ; 9svn B@
[8o!X)
return totalPage; K2u$1OKv
} 9{;cp?\)M
VQQtxHTC3
privatestaticboolean hasPrePage(int currentPage){ K38A;=t9
return currentPage == 1 ? false : true; EN =oA P
} MifPZQ
_ZnVQ,zY
privatestaticboolean hasNextPage(int currentPage, LXIQpD,M
J4Ix\r_
int totalPage){ fg mIx
return currentPage == totalPage || totalPage == &3Q!'pJJ
~ "^]\3#
0 ? false : true; YMidSfi
} wIv_Z^%V
nnV(MB4z1
SOq{`~,4B
} J 5Nz<
3=reN6Q
b#:Pl`n6u
/$
-^k[%
XF`,mV4
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。 D{]t50a.
GvL)SVv?
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 cH&-/|N
(o!v,=# 6{
做法如下: SD "'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 f__r" N
yA8e"$
的信息,和一个结果集List: s<i& q {r
java代码: z$VA]tI(
5Iv3B|u
6^vMJ82U
/*Created on 2005-6-13*/ >IL[eiiPG
package com.adt.bo; Z'P>sV
-'j_JJ
import java.util.List; QEe\1>1"&
$*035f
import org.flyware.util.page.Page; y<Hka'(%
t:DZow
/** N3D{t\hg
* @author Joa X=i^[?C
*/ bbDl?m&bq
publicclass Result { _vQtV]
5BSh`r
private Page page; u!=9.3
VJK?"mX
private List content; Vv"JN?dHi
Uxla,CCp-
/** 82S?@%}#J
* The default constructor ]SqLF!S(=
*/ (;f7/2~`
public Result(){ }:5_vH0
super(); i+x$Y)=
} %^e~;i=2
Q}pnb3J>T
/** ^hG
Y,\K9
* The constructor using fields "|{3V:e>a
* 5_bIc=L1
* @param page <M(Jqb cWa
* @param content 5Ocd2T'
*/ /%E l0X
public Result(Page page, List content){ :6~DOvY
this.page = page; (8M^|z}q
this.content = content; + 9vd(c
} U>0' K3_
tVSURYA8
/** >(v%"04|e
* @return Returns the content. Kk5 vC{
*/ 5|&:l8=
publicList getContent(){ q+A^JjzT
return content; q4].C|7
} n5nV461U
3|$>2IRq
/** Hwr#
NKz-
* @return Returns the page. x?hdC)#DWI
*/ gv&%2e} _
public Page getPage(){ jy=dB-&
return page; #[.vfG
} q#fj?`k
/u9Md 3q*'
/** s%tPGjMq
* @param content TW2OT }
* The content to set. k+X=8()k
*/ GCN(
public void setContent(List content){ Yg 8AMi
this.content = content; "CYh"4]@rD
} 44H#8kV
T6s~f$G
/** 0\G`AO;D
* @param page #;Yn8'a~
* The page to set. 4"$K66yk@
*/ }-3|
v<d
publicvoid setPage(Page page){ AJ'YkSg
this.page = page; 7U#`^Q}
} )9~1XiS,
} >>lT-w
FhJ8}at+e
~z)diF<
FA 1E`AdU
fH_G;#q
2. 编写业务逻辑接口,并实现它(UserManager, P0m;AqS#R
5 pNbO[
UserManagerImpl) qaBjV6loy
java代码: ei 1(A
)^+v*=Dc-i
QcyYTg4i
/*Created on 2005-7-15*/ <v<TsEI
package com.adt.service; lQs|B '
te?R(&
import net.sf.hibernate.HibernateException; hJ8|KPgdw
rvT75dV0
import org.flyware.util.page.Page; 8fpaY{]
27b7~!
import com.adt.bo.Result; ajy.K'B*
8Rq+eOP=S
/** fo])=KM
* @author Joa Lu&2^USTO
*/ EK:!.Fl
publicinterface UserManager { J~z;sTR
7+aTrE{
public Result listUser(Page page)throws n8"S;:Zm
RYMOLX84
HibernateException; v'`9^3(-
]}Hcb)'j@
} Ou IoO
jRXpEiM
J&~nD(&TY
|Ia3b VW
2-821Sf#h
java代码: w5"C<5^
B\&;eZY'G
P>%\pCJ])
/*Created on 2005-7-15*/ -A}*Aa'\
package com.adt.service.impl; y|!%C-P
nf!RB-orF
import java.util.List; )5P*O5kQ -
>`DbT:/<
import net.sf.hibernate.HibernateException; fc lmxTy
GDC`\cy
import org.flyware.util.page.Page; hd1H
import org.flyware.util.page.PageUtil; X ^>o/U
~uRG~,{rH
import com.adt.bo.Result; 0j%@P[zQ
import com.adt.dao.UserDAO; LH..8nfl
import com.adt.exception.ObjectNotFoundException; ,YFuMek
import com.adt.service.UserManager;
GqhnE>
p2|c8n==
/** DG1
>T
* @author Joa 4R\bU"+jZ_
*/ ay#cW.,
publicclass UserManagerImpl implements UserManager { NtMK+y
F.?`<7
private UserDAO userDAO; CtVY;eG
u4B, |_MK
/** >x)YdgJ*
* @param userDAO The userDAO to set. !_s|h@
*/ dz.]5R
publicvoid setUserDAO(UserDAO userDAO){ OxX{[|!`
this.userDAO = userDAO; +4ax~fuU
} a_I!2w<I
ME~ga,|K
/* (non-Javadoc) (r`+q[
* @see com.adt.service.UserManager#listUser PEZElB;
YE&"IH]lF
(org.flyware.util.page.Page) ` 1DJwe2
*/ VE^NSkOa&
public Result listUser(Page page)throws ws
tI8">
i0,{*LD%^
HibernateException, ObjectNotFoundException { RH ow%2D
int totalRecords = userDAO.getUserCount(); sj2v*tFb
if(totalRecords == 0) B?-RzWB\3
throw new ObjectNotFoundException \(.&E`r
:w(J=0Lt
("userNotExist"); Pca~V>Hd
page = PageUtil.createPage(page, totalRecords); PC/fb-J
List users = userDAO.getUserByPage(page); GmtMA|
returnnew Result(page, users); 8,YF>O&
} &T]+g8 ''
YS,kjL/
} }p}i_'%
|8&AsQd
4C[,S|J
+%X_+9bd
x@2rfs
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w(r$n|Ks9
xC`Hm?kM
询,接下来编写UserDAO的代码: l7aGo1TcIh
3. UserDAO 和 UserDAOImpl: wc)[r~On(5
java代码: [ar:zlV8
"Na9Xea
riZFcVsB
/*Created on 2005-7-15*/ t2p/NIn
package com.adt.dao; J=*y>Zt-b
NUH;GMj,,
import java.util.List; >tr?5iKxc
vKAHf;1
import org.flyware.util.page.Page; nX5*pTfjL3
tA#X@HIE
import net.sf.hibernate.HibernateException; 'nP'MA9b;a
vbqI$F[s
/** k}ps-w6:
* @author Joa z:u`W#Rf
*/ MGc=TQ.
publicinterface UserDAO extends BaseDAO { Rt7}e09HV
}Bc'(2A;,
publicList getUserByName(String name)throws KblOP{I
J}jK_
HibernateException; "1%<IqpU+
*^Zt5 zk
publicint getUserCount()throws HibernateException; IS&`O=7
k%hD<_:p
publicList getUserByPage(Page page)throws ~(aq3ngo.
&M>S$+I
n
HibernateException; yel>-=Vn
,EZ&n[%Ko
} 32~Tf,
/lr RbZ
x ?^c:`.
m*i~Vjxj-m
=v:_N.Fh-c
java代码: DIk$9$"<x
.kC}. Q_
q/;mxq$
/*Created on 2005-7-15*/ .&sguAyG
package com.adt.dao.impl; *uEU9fX
`b\4h/~
import java.util.List; 7y[B[$P
l$zNsf.
import org.flyware.util.page.Page; >F+:ej
an5Ss@<4AA
import net.sf.hibernate.HibernateException; Bs# #3{ylu
import net.sf.hibernate.Query; ZM|>Va/X
G x,D'H'
import com.adt.dao.UserDAO; +Og O<P
z?
{#/
/** ?5(L.XFm
* @author Joa ED?s[K
*/ qL'3MY.!
public class UserDAOImpl extends BaseDAOHibernateImpl ?-i|f_`
y.O? c&!
implements UserDAO { IcQ?^9%{
VqbiZOZ@
/* (non-Javadoc) &>s(f-\8
* @see com.adt.dao.UserDAO#getUserByName plf<O5'
@?1%*/
(java.lang.String) t&&OhHK
*/ kqyMrZ#
publicList getUserByName(String name)throws Wt`D
+]>a`~
HibernateException { )`Fr*H3{
String querySentence = "FROM user in class I}q-J~s
r]E$uq
bR
com.adt.po.User WHERE user.name=:name"; %b*%'#iK
Query query = getSession().createQuery c8'8DM
1z`,*eD7
(querySentence); }Sh-4:-D
query.setParameter("name", name); AzV5Re8M
return query.list(); \
bhok
} ~FsUK;?
lvN{R{7>
/* (non-Javadoc) $e_ps~{7$
* @see com.adt.dao.UserDAO#getUserCount() ex=~l O
*/ PWmz7*/
publicint getUserCount()throws HibernateException { XgbGC*dQ
int count = 0; MvW>ktkU
String querySentence = "SELECT count(*) FROM 4tC_W!?$t
P~ykC{nD
user in class com.adt.po.User"; N\fT6#5B
Query query = getSession().createQuery Lg?'1dg
##5/%#eZ
(querySentence); $"i690
count = ((Integer)query.iterate().next f@{C3E dd
ZX0c_Mk=
()).intValue(); n~ql]Ln
return count; HDEG/k/~m
} W<4\4
J
v#^GNm
/* (non-Javadoc) Dr1F|[
* @see com.adt.dao.UserDAO#getUserByPage "uCQm '
f+920/>!Z
(org.flyware.util.page.Page) sfV.X:ev
*/ 6:,^CI|@t
publicList getUserByPage(Page page)throws m\f_u*
r83~o/T@
HibernateException { LC{hoq\
String querySentence = "FROM user in class 8x"d/D
7j:{rCp3J
com.adt.po.User"; q(7D8xG;F
Query query = getSession().createQuery h7$!wf!I
`k&K"jA7$
(querySentence); }#8uXA
query.setFirstResult(page.getBeginIndex()) 50&F#v%YB
.setMaxResults(page.getEveryPage()); gcxk'd
return query.list(); f>dkT'4
} ?U08A{ c
.@Uz/j?>
} G 7]wg>*
3(+#^aw
Hz8`)cv`
r6JkoPMh
=on!&M
至此,一个完整的分页程序完成。前台的只需要调用 3+3m`%G
~ fEs!hl
userManager.listUser(page)即可得到一个Page对象和结果集对象 fR4l4 GU?)
t5X
lR]` w
的综合体,而传入的参数page对象则可以由前台传入,如果用 #@^w>D6W
j7#GqVS'
webwork,甚至可以直接在配置文件中指定。 c)MR+'d\WO
r)(BT:2m
下面给出一个webwork调用示例: VtiqAh}4
java代码: %:KV2GP
q_y,j&
jHlOP,kc
/*Created on 2005-6-17*/ 'S7@+kJ
package com.adt.action.user; G.nftp(*}
h#>L:Wf5E
import java.util.List; !u4Z0 !Ll
>B /&V|E
import org.apache.commons.logging.Log; NK9WrUj)
import org.apache.commons.logging.LogFactory; 8='21@wrN
import org.flyware.util.page.Page; #A9_A%_.h
C6UMc}
9h
import com.adt.bo.Result; S~Iw?SK3
import com.adt.service.UserService; w2N3+Tkg
import com.opensymphony.xwork.Action; k>&s(b
\1mM5r~
/** R``VQ
* @author Joa >Ug?O~-
*/ &1E~ \8U
publicclass ListUser implementsAction{ gSr}p$N
`x$}~rP&)!
privatestaticfinal Log logger = LogFactory.getLog ;5Vk01R
2r}uE\GN
(ListUser.class); J'ZFIT_>
8jjk?PUD8
private UserService userService; 37O#aJ,K
{8#N7(%z
private Page page; {nPkb5xbW
()C^ta_]
privateList users; [p W1=tI
!*?(Q6
/* P10p<@?
* (non-Javadoc) 9U7Mu;4
* #OD@q;
* @see com.opensymphony.xwork.Action#execute() ]~\SR0
*/ ~w1{zxs
publicString execute()throwsException{ N{^>MRK=5
Result result = userService.listUser(page); zY+t ,2z
page = result.getPage(); v$)@AE
users = result.getContent(); qX
p,d
return SUCCESS; F9k
I'<Q
} tB ,.
T6R7,Vt'v
/** I|F~HUzA"
* @return Returns the page. /OhaERv
*/ ^<>Jw%H
public Page getPage(){ hi {2h04
return page; \3Q:K|
} R0Ax$Cv{
(>rS
_#^
/** b`h%W"|2L
* @return Returns the users. FXOT+9bg
*/ e8d5(e
publicList getUsers(){ 6(N.T+;]
return users; ?418*tXd
} i{tTUA
_HWHQF7
/** ^8?j~&u$F
* @param page Y )u_nn'[
* The page to set. gdoJ4b
*/ -H1"OJ2aF
publicvoid setPage(Page page){ JqI6k6~Q^
this.page = page; .k# N7[q=
} CRZi;7`*1
js:C
mnI
/** tA`mD >[
* @param users [c&2i`C
* The users to set. TK;\_yN
*/ //\ds71h
publicvoid setUsers(List users){ PHQ{-b?4t
this.users = users; !Oeq
G
} ^G}# jg.
YHs?QsP
/** t{_!Z(Rt5)
* @param userService OOCQsoN
* The userService to set. +?qf`p.{
*/ iKg75%;t
publicvoid setUserService(UserService userService){ EKcC+g
this.userService = userService; !+m@AQ:,
} jmkRP"ZnA
} FQ+8J 7
(l
Lu?NpIi
,/~[S
e &d3SQ%
|kId8WtA
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, m'd^?Qc
h]qT1(I
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 SV&kWbS
aw1P5aPmX
么只需要: \0D$Mie
java代码: /v5qyR7an
>&BrCu[u
zEy&4Kl{+
<?xml version="1.0"?> iu+3,]7Fm
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork QO@6VY@
u2 7S%2P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- jM*AL
X
26M~<Ic
1.0.dtd"> ^b=XV&{q
=qw&dwIQ
<xwork> oB4#J*
;J'OakeVO
<package name="user" extends="webwork- z4g+2f7h-X
)`<6taKx@n
interceptors"> #'C/Gya
2\5cjdy
<!-- The default interceptor stack name !Vb,zQ
D{R/#vM jk
--> A';n6ne%i
<default-interceptor-ref Pw= 3PvkL
%lV@:"G
name="myDefaultWebStack"/> gGmxx,i
O] H=s
<action name="listUser" p'80d:
K@6`-|I
class="com.adt.action.user.ListUser"> (`pNXQ0n
<param *2=W5LaK.
n26>>N
name="page.everyPage">10</param> y^G>{?Tha
<result PPj[;(A
SW#BZ3L
name="success">/user/user_list.jsp</result> F@1d%c
</action> ~0ooRUWU7
5U~OP
</package> "J!}3)n
uB;_vC
</xwork> -;>#3O-
-w ~(3(
.H2qs{N!
w" JGO
.LObOR5J7
4uUs7T
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 qm'b'!gq~
"yW&<7u1
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。 4\6:\
> :Ze4}(
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ?/'}JS(Sm
9afh[3qm
ax_YKJ5#P
] H&c'
!)c=1EX]"
我写的一个用于分页的类,用了泛型了,hoho .45^=2NGmQ
`(DJs-xD
java代码: s4$X
6Y7H|>g)
yU7I;]YP
package com.intokr.util; Uo6(|mm
*Hs*,}MS
import java.util.List; P+Z\3re
n3ZAF'
/** k)":v3^
* 用于分页的类<br> XdsJwn F
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #s2B%X
* R#qI(V
* @version 0.01 i8~$o:&HT
* @author cheng %{C)1*M7
*/ _ 08];M|
public class Paginator<E> { ;S JF%@x
privateint count = 0; // 总记录数 |nY~ZVTt/
privateint p = 1; // 页编号 \.<KA
privateint num = 20; // 每页的记录数 T2weAk#J
privateList<E> results = null; // 结果 }
`T8A
)a cV-+{
/** ?`AGF%zp
* 结果总数 5v9Vk`3'
*/ q*8lnk
publicint getCount(){ {/}^D-
return count; #3MKH8k&~
} aB"xqh)a}T
OM:v`<T!z
publicvoid setCount(int count){ }1 QF+Cf
this.count = count; 6G_<2bO
} saW!9HQj
?)i1b\4Go
/** G!Zyl^
* 本结果所在的页码,从1开始 &ao(!/im
* ;>ozEh#8w
* @return Returns the pageNo. 8eyl,W=dn
*/ ({[,$dEa;
publicint getP(){ -MfQ&U
return p; p2d\ZgWD=)
} 4%_M27bu[
`w<J25
/** \dkOK`)b
* if(p<=0) p=1 :"'nK6>
* h-mTj3p-K
* @param p S>f&6ZDNY(
*/ Gr)-5qh
publicvoid setP(int p){ T+CajSV
if(p <= 0) k4y}&?$B
p = 1; I>"Ci(N
this.p = p; 9UD
@MA
} BHr|.9g]%%
lG"H4Aa>
/** g.C5r]=+&
* 每页记录数量 Jqfm@Y
*/ +)/Uu3"=
publicint getNum(){ (?Q|s,
return num; 8MF2K6
} (:sZ
b?*
b^Cfhy^RTq
/** ]WL|~mG
* if(num<1) num=1 I>n
g`
*/ 3 ^}A %-bS
publicvoid setNum(int num){ wda';@y5(
if(num < 1) M-MKk:o
num = 1; hbfq]v*X
this.num = num; xRxy|x[
} 3S"] u}
o`? zF+M0
/** .eF_cD7v
* 获得总页数 GozPvR^/
*/ ]U_ec*a
publicint getPageNum(){ +5X DF
return(count - 1) / num + 1; 5%i:4sMx
*
} 3V;gW%>
f[jNwb
/** .6.^G
* 获得本页的开始编号,为 (p-1)*num+1 z2 hFn&
*/ p2 ! FcFi
publicint getStart(){ UA-7nb
return(p - 1) * num + 1; <hvRP!~<)
} !Q%P%P<$
I:=dG[\h2
/** ls|LCQPx
* @return Returns the results. qVgd(?hJ#
*/ C/tr$.2H=
publicList<E> getResults(){ ,sQ93(Vo
return results; \3zj18(@8!
} B3
zk(RNZ
r`M6!}oa
public void setResults(List<E> results){ y8
E}2/
this.results = results; ~[W#/kd1n
} N4{nG,Mo]
1wn&js C
public String toString(){ ?6N3tk-2
StringBuilder buff = new StringBuilder kfrY1
M\2"gT-LV
(); C/@LZ OEL
buff.append("{"); u$*>`Xe6
buff.append("count:").append(count); R: Z_g!h
buff.append(",p:").append(p); `jsEN ;<
buff.append(",nump:").append(num); H[WQ=){
buff.append(",results:").append IOl+t,0x&
q31>uF
(results); wNWka7P*
buff.append("}"); /yPXMJ6W~R
return buff.toString(); vF={9G
} ^twivNB
UT]?;o"
} PlxIfL
I0Ia6w9
HZjf`eM,