ctrl+space
ctrl+t
ctrl+k
ctrl+f8/f9/f10
alt+shift+x , t/j
alt+shift+d , t/j
Command:
cd -
tab
ctrl+a/e
ctrl+u/k/w
Vim
shift+g
m+'mark'
`+'mark'
. (repeat)
]]>
]]>
2 transaction features:
ACID (atomicity, consistency, isolation, durability)
3 java spec
JTA, JTS
1
interface javax.transaction.TransactionManager
2
{
3
public abstract void begin();
4public abstract void commit();
5public abstract int getStatus();
6public abstract Transaction getTransaction();
7public void resume(Transaction tobj);
8public abstract void rollback();
9public abstract void setRollbackOnly();
10public abstract void setTransactionTimeout(intseconds);
11public abstract Transaction suspend() ;
12
}
interface javax.transaction.TransactionManager2
{
3
public abstract void begin();4
public abstract void commit();5
public abstract int getStatus();6
public abstract Transaction getTransaction();7
public void resume(Transaction tobj);8
public abstract void rollback();9
public abstract void setRollbackOnly();10
public abstract void setTransactionTimeout(intseconds);11
public abstract Transaction suspend() ;12
}4 Common XAResource
JDBC 2.0:
A JDBC driver that supports distributed transactions implements the javax.transaction.xa.XAResource interface, the javax.sql.XAConnectioninterface, and the javax.sql.XADataSource interface.
JMS 1.0:
a JMS provider javax.transaction.xa.XAResource interface, the implements the javax.jms.XAConnection and the javax.jms.XASession interface.
5 Common TransactionManager
5.1 EJB Transaction Options:
NotSupported
If the method is called within a transaction, this transaction is suspended during the time of the method execution.
Required
If the method is called within a transaction, the method is executed in the scope of this transaction; otherwise, a new transaction is started for the execution of the method and committed before the method result is sent to the caller.
RequiresNew
The method will always be executed within the scope of a new transaction. The new transaction is started for the execution of the method, and committed before the method result is sent to the caller. If the method is called within a transaction, this transaction is suspended before the new one is started and resumed when the new transaction has completed.
Mandatory
The method should always be called within the scope of a transaction, else the container will throw the TransactionRequired exception.
Supports
The method is invoked within the caller transaction scope; if the caller does not have an associated transaction, the method is invoked without a transaction scope.
Never
The client is required to call the bean without any transaction context; if it is not the case, a java.rmi.RemoteException is thrown by the container.
5.2 Spring transaction:
Transaction isolation: The degree of isolation this transaction has from the work of other transactions. For example, can this transaction see uncommitted writes from other transactions? avaliable options:
ISOLATION_DEFAULT
ISOLATION_READ_UNCOMMITTED
ISOLATION_READ_COMMITTED
ISOLATION_REPEATABLE_READ
ISOLATION_SERIALIZABLE
Transaction propagation: Normally all code executed within a transaction scope will run in that transaction. However, there are several options specifying behavior if a transactional method is executed when a transaction context already exists: For example, simply running in the existing transaction (the most common case); or suspending the existing transaction and creating a new transaction. Spring offers the transaction propagation options familiar from EJB CMT. avaliable options:
PROPAGATION_MANDATORY
PROPAGATION_NESTED
PROPAGATION_NEVER
PROPAGATION_NOT_SUPPORTED
PROPAGATION_REQUIRED
PROPAGATION_REQUIRES_NEW
PROPAGATION_SUPPORTS
Transaction timeout: How long this transaction may run before timing out (automatically being rolled back by the underlying transaction infrastructure).
Read-only status: A read-only transaction does not modify any data. Read-only transactions can be a useful optimization in some cases (such as when using Hibernate).
6 transaction for web service
Protocol specifications:
WS-Transaction
OASIS Business Transaction Protocol (BTP)
Java API
JAXTX (JSR-156)
]]>
1 //wrong: all function refer to global variable i=10
2 var fn_list=[];
3 for(var i=0;i<10;i++){
4 var _tempFn =function(){
5 return i;
6 }
7 fn_list.push(_tempFn);
8 }
9 //right: every function refer to its closure scope variable a
10 var fn_list=[];
11 for(var i=0;i<10;i++){
12 var _tempFn =function(a){
13 return function(){
14 return a;
15 };
16 }
17 fn_list.push(_tempFn(i));
18 }
19
2 var fn_list=[];
3 for(var i=0;i<10;i++){
4 var _tempFn =function(){
5 return i;
6 }
7 fn_list.push(_tempFn);
8 }
9 //right: every function refer to its closure scope variable a
10 var fn_list=[];
11 for(var i=0;i<10;i++){
12 var _tempFn =function(a){
13 return function(){
14 return a;
15 };
16 }
17 fn_list.push(_tempFn(i));
18 }
19
Java閲屼篃鏈変袱涓鍒濆鑰呭鏄撴販娣嗙殑姒傚康錛歯est class and inner class銆?br /> nest class灝辨槸static inner class,
鑰宨nner class灝辨槸no-static inner class銆傛病鏈変負浠涔堬紝sun灝辨槸榪欎箞瀹氫箟鐨勩?br /> 榪樻槸涓婇潰寰椾緥瀛愶紝鍒涘緩10涓璞★紝姣忎釜瀵硅薄鐨刧etValue鎺ュ彛渚濇榪斿洖0-9.
1 public class Test {
2 private int noStaticValue;
3 private static int staticValue;
4
5 public Test(int noSV, int sv) {
6 this.noStaticValue = noSV;
7 this.staticValue = sv;
8 }
9
10 public Test(int noSV) {
11 this.noStaticValue = noSV;
12 }
13
14 interface valueHolder {
15 int getValue();
16 }
17
18 class innerClass implements valueHolder {
19 public int getValue() {
20 return noStaticValue;
21 }
22 }
23
24 static class nestClass implements valueHolder {
25 public nestClass(int i) {
26 staticValue = i;
27 }
28
29 public int getValue() {
30 return staticValue;
31 }
32 }
33
34 public static void main(String[] args) {
35 Test context1 = new Test(0, 0);
36 valueHolder[] list = new valueHolder[10];
37 for (int i = 0; i < 10; i++) {
38 list[i] = new Test.nestClass(i);
39 }
40 for (valueHolder obj : list) {
41 System.out.println(obj.getValue());// always print 9
42 }
43 for (int i = 0; i < 10; i++) {
44 list[i] = new Test(i).new innerClass();
45 }
46 for (valueHolder obj : list) {
47 System.out.println(obj.getValue());// print 0-9
48 }
49 }
50 }
鍙鐢╥nner class鍙互妯℃嫙closure鐨勭壒鎬э紝灝辨槸榪愯鏃跺畾涔塩lass鐨勬煇浜涚姸鎬併?br />
inner class鍜宯est class涔嬮棿鐨勫尯鍒氨鏄悗鑰呮槸闈欐佺被銆傚墠鑰呭繀欏婚氳繃wrap class鐨勫疄渚嬫潵璋冪敤new,e.g. new Test().new innerClass銆?br />
鍥犱負nest class鏄潤鎬佺被錛屾墍浠ュ彲浠ユ坊鍔爏tatic member 鎴栬卻tatic method,鑰宨nner class 涓嶈銆?br />
鍖垮悕鍐呴儴綾繪槸inner class鐨勪竴縐嶇壒孌婂艦寮忥紝鎵浠ヤ篃涓嶈兘娣誨姞static member 鎴栬卻tatic method銆?br />
2 private int noStaticValue;
3 private static int staticValue;
4
5 public Test(int noSV, int sv) {
6 this.noStaticValue = noSV;
7 this.staticValue = sv;
8 }
9
10 public Test(int noSV) {
11 this.noStaticValue = noSV;
12 }
13
14 interface valueHolder {
15 int getValue();
16 }
17
18 class innerClass implements valueHolder {
19 public int getValue() {
20 return noStaticValue;
21 }
22 }
23
24 static class nestClass implements valueHolder {
25 public nestClass(int i) {
26 staticValue = i;
27 }
28
29 public int getValue() {
30 return staticValue;
31 }
32 }
33
34 public static void main(String[] args) {
35 Test context1 = new Test(0, 0);
36 valueHolder[] list = new valueHolder[10];
37 for (int i = 0; i < 10; i++) {
38 list[i] = new Test.nestClass(i);
39 }
40 for (valueHolder obj : list) {
41 System.out.println(obj.getValue());// always print 9
42 }
43 for (int i = 0; i < 10; i++) {
44 list[i] = new Test(i).new innerClass();
45 }
46 for (valueHolder obj : list) {
47 System.out.println(obj.getValue());// print 0-9
48 }
49 }
50 }
]]>
鑷彂鍜屼笓綺句篃璁歌兘鍦ㄤ腑鐭湡緇存寔鍔ㄥ姏錛屼絾鏄暱鏈熶笅鍘伙紝褰撴垜浠笉鐭ラ亾鑷繁涓轟粈涔堝伐浣滅殑鏃跺欙紝鍔ㄥ姏涔熶細琛扮銆傜洰鏍囨ц姹傜洰鏍囦笉鑳藉お浣庤屾病鏈夋垚灝辨劅錛屾垨鑰呭お楂樿屽緢闅捐揪鍒般傛渶濂界殑鐩爣鏄瘮浣犵幇鍦ㄧ殑鎴愬氨鏇撮珮錛屼笖闇瑕佷竴瀹氱殑鍔姏鎵嶈兘杈懼埌銆?br /> Drive: The Surprising Truth About What Motivates Us
]]>
]]>
Cache鐨勭洰鐨勬槸涓轟簡浠ョ┖闂存崲鏃墮棿錛屼竴嬈¤綆楃粨鏋滀負澶氭閲嶇敤銆?br /> 絀洪棿鍙互鏄疄鏃跺唴瀛樼┖闂淬佹寔涔呭寲鐨勭‖鐩樼┖闂淬傛椂闂村彲浠ユ槸榪愮畻鏃墮棿銆佽繛鎺ユ椂闂淬佷紶杈撴椂闂寸瓑銆?br />
Cache鍙互鍒嗕負LocalCache鍜孌istributedCache銆?br /> 鏈綆鍗曠殑LocalCache鍙互閫氳繃緇存姢涓涓狢oncurrentHashMap瀹炵幇銆?br /> 緙虹偣鏄細
1錛屽唴瀛樻湁闄愶紝瀹規槗out of memory 錛堝畾鏈熸竻闄わ紵鎸佷箙鍖栵紵錛?br /> 2, 闇瑕佸鍏╩ap鍋歝oncurrency緇存姢錛岀矖綺掑害鐨勯攣瀹氫簤鐢ㄤ細褰卞搷鎬ц兘錛堟爲緇撴瀯緇存姢錛燂級
鍦ㄤ竴涓笓涓氱殑浼佷笟綰у簲鐢ㄤ腑錛宑ache闄や簡楂樻ц兘鍜岀嚎紼嬪畨鍏ㄧ殑瑕佹眰錛岃繕瑕佹敮鎸佷簨鍔°侀珮鍙敤鎬с佹寔涔呭寲銆佸閿欍侀泦緹ゅ悓姝ョ瓑銆?br /> JBossCache鏄竴涓吀鍨嬬殑浼佷笟綰ache瀹炵幇錛屼粬閲囩敤鏍戠粨鏋勪笖鏀寔闆嗙兢鍜屼簨鍔＄壒鎬с?br /> 铏界劧JBossCache榪欐妸鐗涘垁涔熷彲浠ュ湪standalone鐨凧S2E搴旂敤涓敤鏉ユ潃楦★紝浣嗘垜浠簲璇ユ洿鍏沖績鐢ㄤ粬鍦ㄩ泦緹ょ幆澧冧腑鎬庝箞鏉鐗涖?br /> JBossCache鍒嗕負闈為泦緹ゆā寮?Local)鍜岄泦緹ゆā寮忋?br /> 闆嗙兢妯″紡鏍規嵁瀹炵幇絳栫暐鍙堝垎涓簉eplication鍜宨nvalidation銆?br /> 1 replication錛氶氳繃鎷瘋礉鏀瑰彉鐨刢ache瀵硅薄鏉ヤ繚璇佷笌闆嗙兢涓叾浠朿ache鍚屾銆俽eplication鍙堝彲緇嗗垎涓哄悓姝eplication鍜屽紓姝epliation涓ょ錛屽紓姝eplication杈冨揩,put浠ュ悗椹笂榪斿洖錛屼絾鏄痳eplication鍑洪敊浜嗭紝浜嬪姟榪樻槸綆楀畬鎴愪簡涓嶅洖鍥炴粴銆傚悓姝eplication瑕佽姳鏃墮棿絳夊緟鍏朵粬鐨刢ache瀹屾垚replication鐨勯氱煡鎵嶈兘緇撴潫銆?br />
2 invalidation: 濡傛灉cache鐘舵佹敼鍙橈紝浠呬粎鏄粰鍏朵粬cache鍙戜釜閫氱煡錛屾敹鍒伴氱煡鐨刢ache鎶婅剰鏁版嵁娓呴櫎鎺夈俰nvalidation涔熷彲鍒嗕負鍚屾鍜屽紓姝ヤ袱縐嶏紝鍖哄埆鏄彂閫侀氱煡鐨勫箍鎾柟寮忎竴涓槸鍚屾涓涓槸寮傛銆?br />
鍦╦boss cluster涓紝鎴戜滑鏈濂介氳繃MBean鏉ラ儴緗瞛boss cache銆傝繖鏍峰張鍑犱釜濂藉錛?br /> 1錛孞Boss NS鏀寔Cluster
鎴戜滑灝卞彲浠ラ氳繃JBoss NamingService鏉ヨ闂甤ache銆傚鏋滃湪local NS涓煡涓嶅埌cache錛宩bss NS榪樹細鍘繪煡cluster涓叾浠栫殑cache銆?br /> 2錛屽埄鐢∕Bean鐨勭壒鎬?br /> 閫氳繃CacheMBean, 鎴戜滑鍙互鏂逛究鐨勭鐞咰ache Service錛屽疄鏃剁殑鍚姩銆佸仠姝㈡垨鑰呮敼鍙樹竴浜涢厤緗紝榪樺彲浠ョ洃鎺у埌涓浜沜ache緇熻鏁版嵁銆?br /> 3錛屽埄鐢?a id="d0e1230">microcontainer鐨勭壒鎬?br />
鎴戜滑鍙互閫氳繃閰嶇疆XML鏂囦歡鏉ュ畬鎴恈ache鐩稿叧鐨勬墍鏈夊璞″０鏄庛?/code>綆鑰岃█涔嬶紝灝辨槸鍒╃敤java reflection鍜孉OP鐨勬妧鏈氨涓嶇敤鍐欏０鏄巆ache鐨勪唬鐮佷簡銆?br />
<?xml version="1.0" encoding="UTF-8"?>
<deployment xmlns="urn:jboss:bean-deployer:2.0">
<!-- First we create a Configuration object for the cache -->
<bean name="ExampleCacheConfig"
class="org.jboss.cache.config.Configuration">
build up the Configuration</bean>
<!-- Factory to build the Cache. -->
<bean name="DefaultCacheFactory" class="org.jboss.cache.DefaultCacheFactory">
<constructor factoryClass="org.jboss.cache.DefaultCacheFactory"
factoryMethod="getInstance" />
</bean>
<!-- The cache itself -->
<bean name="ExampleCache" class="org.jboss.cache.CacheImpl">
<constructor factoryMethod="createnewInstance">
<factory bean="DefaultCacheFactory"/>
<parameter><inject bean="ExampleCacheConfig"/></parameter>
<parameter>false</parameter>
</constructor>
</bean>
<!-- JMX Management -->
<bean name="ExampleCacheJmxWrapper" class="org.jboss.cache.jmx.CacheJmxWrapper">
<annotation>@org.jboss.aop.microcontainer.aspects.jmx.JMX(name="jboss.cache:service=ExampleTreeCache",
exposedInterface=org.jboss.cache.jmx.CacheJmxWrapperMBean.class,
registerDirectly=true)</annotation>
<constructor>
<parameter><inject bean="ExampleCache"/></parameter>
</constructor>
</bean>
</deployment>
鍚庤錛?br /> 1錛宩boss cache鐨刵aga鐗堜腑錛岄噰鐢?a >Multi-versioned concurrency control鏉ュ疄鐜板茍鍙戙備笅嬈″啀浠庝腑鎬葷粨涓涓嬪綰跨▼鐨勫涔犮?br /> 2錛宩boss cache閫氳繃緇撳悎visitor pattern鍜宑ommand pattern錛屾妸瀵筩ache node鐨勬搷浣滀笌璁塊棶浠庝腑闅旂鍑烘潵錛屼笉鐢ㄦ敼鍙樻垨鑰呮墿灞昻ode瀵硅薄灝卞彲浠ユ坊鍔犳柊鐨刵ode琛屼負銆備篃灝辨槸寮闂師鍒欍備笅嬈″啀浠庝腑鎬葷粨涓涓嬪嚑縐嶈璁℃ā寮忕殑緇忓吀搴旂敤銆?br />
]]>