Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 gW/QFZjY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %}\ vW
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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 /E;;j9
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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 "^18&>^
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分页支持类: SIj6.RK
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java代码: <XU8a:w'T
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package com.javaeye.common.util; k\Yu5)
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import java.util.List; yLV2>kq
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publicclass PaginationSupport { yp( ?1
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publicfinalstaticint PAGESIZE = 30; XCKY
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privateint pageSize = PAGESIZE; V<
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privateList items; )i},@T8[
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privateint totalCount; !pG+Ak?
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privateint[] indexes = newint[0]; v+|@}9| Z
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privateint startIndex = 0; ?v0A/68s#
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public PaginationSupport(List items, int ~ra#UG\Y8
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totalCount){ 4`?sE*P@`
setPageSize(PAGESIZE); 1\M"`L/
setTotalCount(totalCount); =d:R/Z%,
setItems(items);
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setStartIndex(0); =U)n`#6_j2
} IwZZewb-a
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public PaginationSupport(List items, int azz#@f1
5<'n
totalCount, int startIndex){ 4SX3c:>
setPageSize(PAGESIZE); DQL06`pX/
setTotalCount(totalCount); KIXwx98
setItems(items); o06A=4I
setStartIndex(startIndex); }rFsU\]:q
} i{%z
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public PaginationSupport(List items, int @5<]W+jk4
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totalCount, int pageSize, int startIndex){ D2hAlV)i(
setPageSize(pageSize); P_:?}h\
setTotalCount(totalCount); V{7lltu
setItems(items); 5n&)q=jk=
setStartIndex(startIndex); ==PQ-Ia
} +ZD[[+
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publicList getItems(){ ?NL&x
return items; I;bg?RsF
}
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publicvoid setItems(List items){ a PcGI
this.items = items; {9m!UlTtw
} ~@)-qV^~
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publicint getPageSize(){ n $D}0wSM/
return pageSize; A>&>6O4
} Bd N{[2
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publicvoid setPageSize(int pageSize){ 4iL.4Uj{N
this.pageSize = pageSize; ~T;ajvJ
} P?WT)C2)u
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publicint getTotalCount(){ u"Hd55"&
return totalCount; /
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} :$X4#k<
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publicvoid setTotalCount(int totalCount){ a[d{>Fb.
if(totalCount > 0){ i;uG:,ro
this.totalCount = totalCount; j?Jd@(*y$
int count = totalCount / (e bBH
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pageSize; 9;xL!cy
if(totalCount % pageSize > 0) .:|#9%5
count++; 0NuL9
indexes = newint[count]; ~L4*b*W
for(int i = 0; i < count; i++){ w|hyU4- ^
indexes = pageSize * rH#c:BwSm
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} qxecp2>U
}else{ /64^5DjTh
this.totalCount = 0; toYg$IV
} +r#=n7t
} 5Xy^I^J
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publicint[] getIndexes(){ )N%1%bg^-
return indexes; FS]+s>
} MK!]y8+Z
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publicvoid setIndexes(int[] indexes){ t?#vb}_
this.indexes = indexes; ]C!Y~
} 8g2-8pa{
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publicint getStartIndex(){ m_PrasZ>
return startIndex; 9L)&n.t1
} r-\T}e2Gz
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publicvoid setStartIndex(int startIndex){ ;?HZ,"^I
if(totalCount <= 0) AT'_0>x8
this.startIndex = 0; dWq/)%@t
elseif(startIndex >= totalCount) )W}/k$S
this.startIndex = indexes ]B-$p p
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[indexes.length - 1]; ^S;RX*
elseif(startIndex < 0) J}Z_.:JO(w
this.startIndex = 0; DbNi;m
else{ A aF5`
this.startIndex = indexes kgbr+Yw2X
>1)@n3. <O
[startIndex / pageSize]; 1X!f!0=g+
} lJz?QI1
} "DcueU#!
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publicint getNextIndex(){ i1_>>49*
int nextIndex = getStartIndex() + Kj1#R
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pageSize; 6UzT]" LR;
if(nextIndex >= totalCount) ]`i@~Z h\
return getStartIndex(); 2'UFHiK
else n\8[G[M
return nextIndex; @qr3v>3X<
} E't G5,/m
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publicint getPreviousIndex(){ ~"<VUJ=Ly:
int previousIndex = getStartIndex() - p?`|CE@h7
+<9q]V
pageSize; /NN[gz
if(previousIndex < 0) ,h(f\h(9
return0; JXy667_
else /K<GN7vN
return previousIndex; gkq RO19
} Xw}Y!;<IEu
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} f29HQhXqS
@ !O&b%8X%
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抽象业务类 ^D>M Dj6
java代码: 5z(>4 d!
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/** Z :i"|;
* Created on 2005-7-12 .Zo9^0`C
*/ ~C*6V{Tj
package com.javaeye.common.business; a ~iEps
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import java.io.Serializable; t=pkYq5t8
import java.util.List; '/qe#S
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import org.hibernate.Criteria; \z2hXT@D
import org.hibernate.HibernateException; u b>K^
import org.hibernate.Session; H1b%:KRVK
import org.hibernate.criterion.DetachedCriteria; g2b4 ia!L
import org.hibernate.criterion.Projections; f}9`iN=k
import q D>Y}Z!
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org.springframework.orm.hibernate3.HibernateCallback; \#oV<MR
import Ckl]fy@D}
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org.springframework.orm.hibernate3.support.HibernateDaoS "ZPbK$+=yU
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upport; 6;c{~$s~[
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import com.javaeye.common.util.PaginationSupport; +7vh_ _
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public abstract class AbstractManager extends @_(@s*4W
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HibernateDaoSupport { T+{'W
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privateboolean cacheQueries = false; Ywb)h^{!
*CD=cmdD*
privateString queryCacheRegion; h|>n3-k|p
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publicvoid setCacheQueries(boolean H&Lbdu~E
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cacheQueries){ :7;Iy u
this.cacheQueries = cacheQueries; p{#7\+}
} 3eDx@8N
}
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publicvoid setQueryCacheRegion(String /n}V7
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queryCacheRegion){ Uz8C!L ">C
this.queryCacheRegion = #7:9XID /
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queryCacheRegion; o;-!?uJ
} gwjv&.T6^
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publicvoid save(finalObject entity){ YG+Yb{^"
getHibernateTemplate().save(entity); (#Kvm
} 6h*bcb#C
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publicvoid persist(finalObject entity){ iQj{J1V
getHibernateTemplate().save(entity); jQlK-U=oi
} rG%_O$_dO
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publicvoid update(finalObject entity){ x@\'@>_GM
getHibernateTemplate().update(entity); G8c}re
} }pZnWK+
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publicvoid delete(finalObject entity){ -Z&{$J
getHibernateTemplate().delete(entity); +|w~j#j9`
} aRKG)0=
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publicObject load(finalClass entity, e ^&8x
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finalSerializable id){ ,
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return getHibernateTemplate().load s-DL=MD
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(entity, id); ]
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} Mj;'vm7#'
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publicObject get(finalClass entity, ?S7:KnU>K
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finalSerializable id){ Nfvg[c
return getHibernateTemplate().get 6$;)CO!h
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(entity, id); r?>Hg+
} @g2L=XF
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publicList findAll(finalClass entity){ TBp5xz`
return getHibernateTemplate().find("from #gT^hl5/
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" + entity.getName()); R63d
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} nvs7s0@Fqe
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publicList findByNamedQuery(finalString wi
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namedQuery){ |hyr(7
return getHibernateTemplate v0J1%{/xs
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().findByNamedQuery(namedQuery); @Ec9Do>
} >#|Q,hVU5
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publicList findByNamedQuery(finalString query, /;ITnG
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finalObject parameter){ |0 %UM}
return getHibernateTemplate Jxp'.oo[
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().findByNamedQuery(query, parameter); J#WPXE+Ds
} Kf5 p*AI
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publicList findByNamedQuery(finalString query, wfzb:Aig`
]<= t
finalObject[] parameters){ sVnuSm
return getHibernateTemplate # nhAW
#| Po&yu4R
().findByNamedQuery(query, parameters); +rX,Sl`/
} U#4W"1~iX
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publicList find(finalString query){ DF =.G1
return getHibernateTemplate().find W=w@SO_?wp
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(query); K`<P^XJr
} xFnMXht
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publicList find(finalString query, finalObject ~h.B\Sc]Q
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parameter){ y~[So ,G
return getHibernateTemplate().find _m-r}9au
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(query, parameter); D1k]
} XrF9*>ti?
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public PaginationSupport findPageByCriteria lU&IS?^?
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(final DetachedCriteria detachedCriteria){ DdgFBO
return findPageByCriteria B~rK3BS
&x #5-O'
(detachedCriteria, PaginationSupport.PAGESIZE, 0); j>23QPG`6U
} lHXH03
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public PaginationSupport findPageByCriteria X}Fv*
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(final DetachedCriteria detachedCriteria, finalint yvvR%]!.
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startIndex){ 3]P=co@
return findPageByCriteria F\;1:y~1
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(detachedCriteria, PaginationSupport.PAGESIZE, ?K"]XXsI
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startIndex); @P?*<b{
} ^D)C|T
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public PaginationSupport findPageByCriteria #oI`j
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(final DetachedCriteria detachedCriteria, finalint %LyB~X
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pageSize, [<hiOB
finalint startIndex){ ^M"g5+q
return(PaginationSupport) ,D1QJPM
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getHibernateTemplate().execute(new HibernateCallback(){ uwJkqlUOz
publicObject doInHibernate 1+'3{m \5T
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(Session session)throws HibernateException { *h1@eJHMz
Criteria criteria = )U`
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detachedCriteria.getExecutableCriteria(session); rxA<\h,A
int totalCount = QB3AL;7
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((Integer) criteria.setProjection(Projections.rowCount -_+0[Nb.
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()).uniqueResult()).intValue(); y- YYDEl
criteria.setProjection sQw-#f7t
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(null); Rk<:m+V=
List items = (_2eiE71
5:wf"3%%
criteria.setFirstResult(startIndex).setMaxResults _C?K;-v}
]@EjKgs
(pageSize).list(); "q8wEu,z[
PaginationSupport ps = cP,jC(<N
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new PaginationSupport(items, totalCount, pageSize, `{%*DHa
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startIndex); P+xZaf
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return ps; &
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} ^H'#*b0u
}, true); K^+B"
} Q5ux**(Wr
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public List findAllByCriteria(final @47TDCr
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DetachedCriteria detachedCriteria){ x=k$^V~
return(List) getHibernateTemplate Dqki}k~{
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().execute(new HibernateCallback(){ ,=FYf|Z
publicObject doInHibernate %2.T1X%!
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(Session session)throws HibernateException { r?$\`,;
Criteria criteria = &nq[Vy0kO4
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detachedCriteria.getExecutableCriteria(session); kDrGl{U}
return criteria.list(); < mxUgU
} LxbVRw
}, true); F]&9Lp}
"
} j>U.(K
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public int getCountByCriteria(final *UTk. :G5
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DetachedCriteria detachedCriteria){ cWi2Sls
Integer count = (Integer) mEA w^
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getHibernateTemplate().execute(new HibernateCallback(){ 2:]Sy4K{
publicObject doInHibernate 0o#lB^e;l
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(Session session)throws HibernateException { x?k6ek
Criteria criteria = q+ .=f.+Z
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detachedCriteria.getExecutableCriteria(session); 9wYbY* j
return y
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criteria.setProjection(Projections.rowCount #(7OvW+y
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()).uniqueResult(); /a,q4tD@
} ,Vogo5~X
}, true); (wTg aV1
return count.intValue(); :F_U^pyG
} te`4*t
} It4F;Ah
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用户在web层构造查询条件detachedCriteria,和可选的 __a9}m4i7x
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4:K9FqU
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PaginationSupport的实例ps。 GK)hK-
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ps.getItems()得到已分页好的结果集 \d6A<(!=v
ps.getIndexes()得到分页索引的数组 {BF$N#7
ps.getTotalCount()得到总结果数 u}pLO9V"`
ps.getStartIndex()当前分页索引 D =3NI
ps.getNextIndex()下一页索引 R_-.:n%.z
ps.getPreviousIndex()上一页索引 %rf<YZ.\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?&[`=ZVn
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 P:Bg()
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一下代码重构了。 5-MI7I@l
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我把原本我的做法也提供出来供大家讨论吧: +Ix;~
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首先,为了实现分页查询,我封装了一个Page类: CrK}mbe
java代码: YM5;mPR
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/*Created on 2005-4-14*/ -ohqw+D
package org.flyware.util.page; <FP&1Eg!|
0(]C$*~mk
/** z+;+c$X
* @author Joa Wu:evaZ:i
* `CRW2^g
*/ {`{U\w5Af
publicclass Page { R+P1 +5
`}1 8A.K
/** imply if the page has previous page */ t1D6#JP(a
privateboolean hasPrePage; @xmL?wz
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/** imply if the page has next page */ BYRf MtT@+
privateboolean hasNextPage; SI-s:%O
M-eX>}CDm
/** the number of every page */ -2f_e3jF
privateint everyPage; Lb(=:Z!{
) !3sB{H
/** the total page number */ F6yMk%
privateint totalPage; h/5.>[VwDh
f`T#=6C4|
/** the number of current page */ +dlN^P647
privateint currentPage; |'.\}xt7
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/** the begin index of the records by the current QO~!S_FRH
h^cM#L^B
query */ 3b~k)t4R
privateint beginIndex; rxt)l
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/** The default constructor */ 86oa>#opU
public Page(){ ?m0|>[j
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} Ju#
- >]
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/** construct the page by everyPage ',~,hJ0
* @param everyPage I~|.Re9a
* */ xzh`q
public Page(int everyPage){ X$)<>e]!>
this.everyPage = everyPage; bDK72cQ
} Rjt]^gb!*
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/** The whole constructor */ :hC+r=!I
public Page(boolean hasPrePage, boolean hasNextPage, "|`euxYV
)17CG*K1
x:4:G(
int everyPage, int totalPage, @!`x^Tzz
int currentPage, int beginIndex){ 4YMX;W
this.hasPrePage = hasPrePage; s9X?tWuL
this.hasNextPage = hasNextPage; 0sIwU!=vm
this.everyPage = everyPage; T'!7jgk{:
this.totalPage = totalPage; ^z)p@sk#
this.currentPage = currentPage; t[VA|1gG
this.beginIndex = beginIndex; 22$M6Qof]n
} "&W80,O3
z&Cz!HrS
/** @p"m{
* @return ]2Zl\}GwY
* Returns the beginIndex. },+ &y^
*/ o !bV;]
publicint getBeginIndex(){ j"1#n? 0
return beginIndex; DxoW,GW
} GKIO@!@[
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/** >cJf D9-<h
* @param beginIndex aYW9C<5
* The beginIndex to set. @~sJ
((G[5
*/ u7L&cx
publicvoid setBeginIndex(int beginIndex){ F!ZE4S_
this.beginIndex = beginIndex; ^ZuwUuuf
} ebfT%_N
grrM[Y7#~b
/** UU'0WIbY6
* @return a]\l:r
* Returns the currentPage. 4h~CDy%_
*/ pr-=<[ d
publicint getCurrentPage(){ _Fkz^B*
return currentPage; #p$iWY>e~
} y rH@:D/
=Z}$X:
$
/** j]P'xrWl]8
* @param currentPage z[|2od
* The currentPage to set. iC2``[m"
*/ -?z#
publicvoid setCurrentPage(int currentPage){ )xm[m vt
this.currentPage = currentPage; {#y~ Qk;T
} x18(}4
OGcq]ue
/** 5v5)vv.kd
* @return p4-UW;Xu
* Returns the everyPage. n37P$0
*/ Q?xA))0
publicint getEveryPage(){ [3 D*DyQt
return everyPage; s_o{w"3X
} z;iNfs0i$
wAD%1;
/** l$Y*ii
* @param everyPage pT|l "q@
* The everyPage to set. tzJ7wXRr
*/ aGBUFCCa
publicvoid setEveryPage(int everyPage){ u43W.4H13
this.everyPage = everyPage; [|A;{F#
} @k+K_gR
/Ixv{H)H
/** f*o+g:]3
* @return L _D #
* Returns the hasNextPage. z=/&tRe
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*/ YC[cQX
publicboolean getHasNextPage(){ 7D&O5Z=%+
return hasNextPage; /#}o19(-d
} ;x.5_Xw{.
3FY87R
/** j[CXIz?c
* @param hasNextPage 2:oAS
* The hasNextPage to set. y=!7PB_\|
*/ %\^VxM
publicvoid setHasNextPage(boolean hasNextPage){ L;h|Sk]{
this.hasNextPage = hasNextPage; e1Q
} %-fQ[@5
swKqsN.
/** ^|%u%UR
* @return r(j :C%?}C
* Returns the hasPrePage. ;W{2\ Es
*/ 70-nAv
publicboolean getHasPrePage(){ hh!4DHv
return hasPrePage; <c%
} Z\r?>2
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/** g o9tvK
* @param hasPrePage C <Pd_&
* The hasPrePage to set. #$X _,+<HZ
*/ qr4.s$VGs*
publicvoid setHasPrePage(boolean hasPrePage){ mor[AJ
this.hasPrePage = hasPrePage; ',Y`\X
} fG zx;<0P!
<
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/** ~jJF&*)
* @return Returns the totalPage. /%1-tGh
* zJ)`snN|
*/ % oJH 6F
publicint getTotalPage(){ ]TVc 'G;
return totalPage; _1G;!eO
} G5hf m-
4s9qQ8?
/** m
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* @param totalPage <&kl:|
* The totalPage to set. os n ,kD*
*/ +2+|zXmT
publicvoid setTotalPage(int totalPage){ oT0:Ny
this.totalPage = totalPage; [gGo^^aW#
} 4Ss*h,Y
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} kho$At)V
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V%'' GF
L 8J] X7
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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 ;#L]7ZY9:-
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个PageUtil,负责对Page对象进行构造: D@ %!|:
java代码: &PPYxg<
40aD\S>
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/*Created on 2005-4-14*/ }Te+Rv7{E
package org.flyware.util.page; 'w0?-
eus@;l*
import org.apache.commons.logging.Log; K5 EJ#1ov
import org.apache.commons.logging.LogFactory; t>P[Yld"
G<P/COI#M5
/** [0D.+("EW
* @author Joa q'9;
* [e>2HIS,
*/ Ap~6Vu
publicclass PageUtil { XVF!l>nE
5Y 7 %Z
privatestaticfinal Log logger = LogFactory.getLog m2HO .ljc
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(PageUtil.class); +7{8T{
oT|:gih5
/** @~&|BvK% \
* Use the origin page to create a new page 1:RK~_E
* @param page Wr@q+Whq
* @param totalRecords zSjZTA/Z
* @return j$<g8Bg=o
*/ 85q!FpuH
publicstatic Page createPage(Page page, int `_sKR,LhB
XqGa]/;}
totalRecords){ I+QM":2
return createPage(page.getEveryPage(), #r,!-;^'p
cd`P'GDF
page.getCurrentPage(), totalRecords); g 'Wr+(A_
} Z5g*'
MO?
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/** )Fw#]~Z
* the basic page utils not including exception y Ni3@f
hY/qMK5
handler Kpkpr`:)]
* @param everyPage He%v 4S
* @param currentPage >3,}^`l
* @param totalRecords @YVla!5O@
* @return page ^9]g5.z:
*/ H6Ytp^~>
publicstatic Page createPage(int everyPage, int _0y]U];ce
OKAmw>{
currentPage, int totalRecords){ 21my9Ui]
everyPage = getEveryPage(everyPage); wb%4f6i
currentPage = getCurrentPage(currentPage); *uSlp_;kB
int beginIndex = getBeginIndex(everyPage, ZENblh8fs
+Ht(_+To1
currentPage); _;R#B`9Iu
int totalPage = getTotalPage(everyPage, TrNh,5+b
Q3'P<"u
totalRecords); q;#bFPh
boolean hasNextPage = hasNextPage(currentPage, -v:3#9uX)
,kUg"\_k
totalPage); ,4k3C#!.i
boolean hasPrePage = hasPrePage(currentPage); @vL0gzE?nB
|"[;0)dw^
returnnew Page(hasPrePage, hasNextPage, a5(9~.9
everyPage, totalPage, pU<GI@gU
currentPage, T)tTzgLD}
t~$8sG\
beginIndex); AF,;3G
} FxT]*mo
*\_>=sS x;
privatestaticint getEveryPage(int everyPage){ $h}w:AV:
return everyPage == 0 ? 10 : everyPage; gB>AYL%o=
} iVo-z#
lk`|u$KPz
privatestaticint getCurrentPage(int currentPage){ )` S5>[6
return currentPage == 0 ? 1 : currentPage; L8oqlq(
9
} fl40jo]
8@){\.M
privatestaticint getBeginIndex(int everyPage, int a
p( PI?]X
'*EKi
currentPage){ >;#rK@*&
return(currentPage - 1) * everyPage; Y5P9z{X=
} ERIF#EY
WqS$C;]%
privatestaticint getTotalPage(int everyPage, int rCb$^(w{7
(!?%"e
totalRecords){ 3HNm`b8G4m
int totalPage = 0; i~3\dp
brK7|&R<
if(totalRecords % everyPage == 0) b&]z^_m)
totalPage = totalRecords / everyPage; GnCs_[*&r
else *^XMf
totalPage = totalRecords / everyPage + 1 ; e.Jaq^Gw|
i>C%[dk9
return totalPage; _n4_;0
} i2-]Xl
=4L%A=]`
privatestaticboolean hasPrePage(int currentPage){ `-Tb=o}.
return currentPage == 1 ? false : true; MwL!2r
} /7ShE-.5#
F&Rr&m
privatestaticboolean hasNextPage(int currentPage, 79D;0
Rl_1g`84
int totalPage){ gQ|?~hYYv
return currentPage == totalPage || totalPage == "`mG_qHI[
"D:?l`\o
0 ? false : true; fhha-J
} sn
Ou
O>i]*V
b?<@
} QWWI
crx%;R
|QQ(1#d
jthyZZ
V2:S
9vO'
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。 I|2dV9y
Y=H_U$
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 }*!_M3O
p^Z|$aZZ
做法如下: [.$/o}
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a/rQ@ c>
DcC|oU[
的信息,和一个结果集List: d7uS[tKqg
java代码: #Fgybokm
2Ky|+s[`[
{bC(>k|CQ
/*Created on 2005-6-13*/ fP- =wd
package com.adt.bo; jF(R;?,
zQ+
%^DT1
import java.util.List; F3 g$b,RMH
6KE64: \;
import org.flyware.util.page.Page; 7f*b5$+r
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/** j'Gezx^.<e
* @author Joa &g=6K&a$a
*/ tVNFulcz$
publicclass Result { .x}xa
1suP7o A;
private Page page; 9lkl-b6xG
.3SP#mI
private List content; !
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-I z,vd
/** TxKNDu
* The default constructor dsK*YY jH
*/ ;Y`8Ee4vH
public Result(){ !u/c'ZLZ>
super(); i-4?]h k
} OLGMy5
@Y ?p-&
/** cnDF`7xrT
* The constructor using fields A6xN6{R!
* [Kb)Q{=)
* @param page @HY P_hR
* @param content kkOjAp{<t
*/ ;g?o~ev 8
public Result(Page page, List content){ x4`|[
this.page = page; k`\L-*:Ji
this.content = content; +xU=7chA
} 7c<_j55(
&Gm3
/** z)R\WFBW
* @return Returns the content. RF~c/en
*/ #8%~ u+"N
publicList getContent(){ 821
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return content; M(ie1Ju
} G*-7}7OAs
BDX>J3h
/** UI wTf2B
* @return Returns the page. /<J5?H
*/ |T*t3}
public Page getPage(){ 3g0v,7,Zv
return page; YdYaLTz
} qy-Hv6oof
%4/X;w\3
/** g}BS:#$
* @param content kZc Ge*
* The content to set. Re1}aLd
*/ 5X9*K
public void setContent(List content){ ?9~|K/ `l
this.content = content; bV*q~@xh
}
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z:08;}t
/** !1<>][F
* @param page `R-VJR 2"
* The page to set. c=Zurqj
*/ m'2EiYX$}\
publicvoid setPage(Page page){ )-i (%;,*e
this.page = page; #BI6+rfv|
} , lBHA+@
} h0l_9uI
Slp_o\s$@
(cp$poo
QD
0p
iP?lP= M
2. 编写业务逻辑接口,并实现它(UserManager, 7V"Jfh4_
H$,wg!kY!
UserManagerImpl) ~S0T+4$
java代码: %D ,(S-Uj
1Nz#,IdQ
$
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/*Created on 2005-7-15*/ h|EHK!<"8
package com.adt.service; x`K"1E{2
'~x jaa;.
import net.sf.hibernate.HibernateException; u}jC$T>2%6
|+1k7S,
import org.flyware.util.page.Page; z~jk_|?|?
&qm:36Y7Xg
import com.adt.bo.Result; Eq5X/Hx
%,udZyO3uR
/** }jL4F$wC
* @author Joa ItG|{Bo
*/ n&E/{o(
publicinterface UserManager { X-SR0x
,(kaC.Em
public Result listUser(Page page)throws J^mm"2
oho~?.F
HibernateException; WAVEwA`r
iv6bXV'N
} t k+t3+
3`ze<K((
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^ E3 HY@j
{<2q
java代码: l,
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w)}@svv"
V&d?4i4/Q
/*Created on 2005-7-15*/ -M-y*P)
package com.adt.service.impl; f/i[?
gw
\>e>J\t:
import java.util.List; deutY.7g
T{Yk/Z/}?
import net.sf.hibernate.HibernateException; *35o$P46
wtfM}MW\
import org.flyware.util.page.Page; rmdG"s
import org.flyware.util.page.PageUtil; DE$T1pFV
N||s#
import com.adt.bo.Result; [Ib17#74
import com.adt.dao.UserDAO; z_:r&UP`"
import com.adt.exception.ObjectNotFoundException; ,.,Y{CP
import com.adt.service.UserManager; TA+/35^?
<}AmzeHr+
/** OJ}aN>k
* @author Joa mtNB09E(
*/ 62>/0_m5
publicclass UserManagerImpl implements UserManager { L$}'6y/@
oRl@AhS
private UserDAO userDAO; @Hst-H.l<l
+/Vzw
/** BWsD~Ft
* @param userDAO The userDAO to set. $)7Af6xD
*/ |bjLmGb
publicvoid setUserDAO(UserDAO userDAO){ ,jMV
#H[
this.userDAO = userDAO; g)iw.M2
} _B\X&!G.
#M8>)o c
/* (non-Javadoc) Jl89}Sf
* @see com.adt.service.UserManager#listUser &3Mps[u:h
&sS]h|2Z5
(org.flyware.util.page.Page) Y\{lQMCy
*/ Wr.~Ns<
public Result listUser(Page page)throws rXnG"A
GC~N$!*
HibernateException, ObjectNotFoundException { ,CnUQx0
int totalRecords = userDAO.getUserCount(); /Pa<I^-#
if(totalRecords == 0) 90+Hv:wF
throw new ObjectNotFoundException Jv:|J
DZ'
t($z+C<
("userNotExist"); 6 bt{j
page = PageUtil.createPage(page, totalRecords); BC1P3Sk
6X
List users = userDAO.getUserByPage(page); +F6R@@rWr
returnnew Result(page, users); 0"=}d y
} H3qL&xL
n`7n5M*
} &/lmg!6
/M~rmIks
p2o66t
IR*:i{
3S1`av(tD
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +4Lj}8,
p:8]jD@}%
询,接下来编写UserDAO的代码: kA&ul
3. UserDAO 和 UserDAOImpl: wGA%h.[M|
java代码: =|bW >y
eR5+1b
nB86oQ/S
/*Created on 2005-7-15*/ 1V1T1
package com.adt.dao; m{sch`bP
=_H)5I_\
import java.util.List; .#ATI<t
*wfkjG
import org.flyware.util.page.Page; ak;S Ie
.;~K*GC
import net.sf.hibernate.HibernateException; ]lzOz<0q
Z(fhH..T`
/** &SK=ZOKg^
* @author Joa CI,xp
*/ Q*AgFF%wn
publicinterface UserDAO extends BaseDAO { T 9?!.o
VEg/x z4c
publicList getUserByName(String name)throws AkRZUj\
_k.gVm
HibernateException; 6 0Obek`
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publicint getUserCount()throws HibernateException; eE;")t,
'k[gxk|d2
publicList getUserByPage(Page page)throws G6x 2!Ny
sOW,hpNW
HibernateException; F`YxH*tO7
Z'z~40Bda
} S~ 3|
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JSm3ZP|GqJ
k~b8=$
f7QX"p&P
java代码: f^X\ N/
pGGx.&5#82
hKW!kA=gZ
/*Created on 2005-7-15*/ ._z[T@!9
package com.adt.dao.impl; pvJPMx
S~DY1e54GF
import java.util.List; 4i o02qd
4
7 }sj&
import org.flyware.util.page.Page; 6KI< J*Wz`
)hai?v~g
import net.sf.hibernate.HibernateException; ;M Z@2CO
import net.sf.hibernate.Query; \M`fkR,,'
1)m&6:!b
import com.adt.dao.UserDAO; C\dlQQ
OT5'c l
/** BV
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* @author Joa 2nPU $\du
*/ JP<Z3
A2q
public class UserDAOImpl extends BaseDAOHibernateImpl ~0>{PD$@
<=,KP)
implements UserDAO { >h
m<$3
wc'K=;c
/* (non-Javadoc) lCyp&b#(L
* @see com.adt.dao.UserDAO#getUserByName XL7jUi_4:L
n`hes_{,g
(java.lang.String) s~6irf/
*/ L"6@3
publicList getUserByName(String name)throws kY6))9 O
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HibernateException { e?D,=A4mV"
String querySentence = "FROM user in class %C[ ;&
z[wk-a+w
com.adt.po.User WHERE user.name=:name"; Kv:ih=?
Query query = getSession().createQuery Zb7:qe<UN
=JnUTc_u
(querySentence); ico(4KSk
query.setParameter("name", name); c!%:f^7g
return query.list(); 'HV}Tr
} PF(P"f.?D
,uP1U@Cas
/* (non-Javadoc) AcF;5h
* @see com.adt.dao.UserDAO#getUserCount() 1dK^[;v>3
*/ /vB%gqJvX
publicint getUserCount()throws HibernateException { gU}?Yy
int count = 0; 7M1*SC
String querySentence = "SELECT count(*) FROM T<0Bq"'%
:q4Mnr
user in class com.adt.po.User"; "zO+!h'o
Query query = getSession().createQuery i4"xvLK4
FBPT@`~v
(querySentence); a|\_'#
count = ((Integer)query.iterate().next ~>)GW
\0pJ+@\T9
()).intValue(); WiL~b
=fT
return count; P
+ nT%
} mYk5f_}
4>^ %_Xj[
/* (non-Javadoc) n.y72-&v
* @see com.adt.dao.UserDAO#getUserByPage AsM""x1Ix
hGF(E*
(org.flyware.util.page.Page) viBf".
*/ N3H!ptn37
publicList getUserByPage(Page page)throws >}/"gx
+*
)Qi)
HibernateException { Q_#X*I
String querySentence = "FROM user in class z@ A5t4+3
1W
HR;!u
com.adt.po.User"; ? F fw'O
Query query = getSession().createQuery $/45*
,Fg&<Be}Jx
(querySentence); 0r=Lilu{q
query.setFirstResult(page.getBeginIndex()) s/Wg^(&M
.setMaxResults(page.getEveryPage()); r/L3j0
return query.list(); DRVvW6s
} v4|kiy
N1(}3O
} SJ7>*Sa(u$
j&Ayk*
i4!n Oyk
(s{%XB:K
Af0E_
至此,一个完整的分页程序完成。前台的只需要调用 a@,tf'Sr
S-yd-MtQp
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?#D@e5Wf
Z#;ieI\
的综合体,而传入的参数page对象则可以由前台传入,如果用 e= "/oo
=W ! m`
webwork,甚至可以直接在配置文件中指定。 lLtC9:
^O\tN\g;c
下面给出一个webwork调用示例: \{+7`4g
java代码: m$hSL4N
O,JthlAV4
=OO_TPEZ
/*Created on 2005-6-17*/ uD:O[H-x
package com.adt.action.user; r:Cad0xj;^
Q:VD2<2
import java.util.List; ,bmTBZV
9LJ/m\bi
import org.apache.commons.logging.Log; nhXa&Nro
import org.apache.commons.logging.LogFactory; rmQGzQnun
import org.flyware.util.page.Page; /yrR
f;}<O
~`_nw5y
import com.adt.bo.Result; .#WF'
import com.adt.service.UserService; ",8h>eEWK
import com.opensymphony.xwork.Action; 7@tr^JykO
5I(`
s#O
/** !b _<_Y{l
* @author Joa s[s 6E`Q
*/ zLXtj-
publicclass ListUser implementsAction{ $X*$,CCIB
//Tr=!TQu
privatestaticfinal Log logger = LogFactory.getLog $9QVl
}>frK#S
(ListUser.class); "
31C8
9CBB,
private UserService userService; V(!b!i@
[V jd)%
private Page page; y'yaCf
ha8do^x
privateList users; -U/&3
J;T_9
/* q9WSQ$:z8
* (non-Javadoc) 5K6_#g4"
* MB "?^~Sm
* @see com.opensymphony.xwork.Action#execute() Va*Uwy?x/)
*/ ,$;CII
v
publicString execute()throwsException{ .=@M>TZM
Result result = userService.listUser(page); dqKTF_+VhA
page = result.getPage(); +Qc^A
users = result.getContent(); p Y>yJ)
return SUCCESS; Ca1)>1Vz
} u5CT7_#)
&