Question
How do you delete a Cookie within a JSP? (JSP)
Answer
Cookie mycook = new Cookie("name","value");
response.addCookie(mycook);
Cookie killmycook = new Cookie("mycook","value");
killmycook.setMaxAge(0);
killmycook.setPath("/");
killmycook.addCookie(killmycook);
Question
How many types of protocol implementations does RMI have? (RMI)
Answer
RMI has at least three protocol implementations: Java
Remote Method Protocol(JRMP), Internet Inter ORB Protocol(IIOP),
and Jini Extensible Remote Invocation(JERI). These are alternatives,
not part of the same thing, All three are indeed layer 6 protocols for
those who are still speaking OSI reference model.
Question
What are the different identifier states of a Thread?
(Core Java)
Answer
The different identifiers of a Thread are:
R - Running or runnable thread
S - Suspended thread
CW - Thread waiting on a condition variable
MW - Thread waiting on a monitor lock
MS - Thread suspended waiting on a monitor lock
Question
What is the fastest type of JDBC driver? (JDBC)
Answer
JDBC driver performance will depend on a number of
issues:
(a) the quality of the driver code,
(b) the size of the driver code,
(c) the database server and its load,
(d) network topology,
(e) the number of times your request is translated to a different API.
In general, all things being equal, you can assume that the more your
request and response change hands, the slower it will be. This
means that Type 1 and Type 3 drivers will be slower than Type 2
drivers (the database calls are make at least three translations versus
two), and Type 4 drivers are the fastest (only one translation).
Question
Request parameter How to find whether a parameter
exists in the request object?
(Servlets)
Answer
1.boolean hasFoo = !(request.getParameter("foo") ==
null || request.getParameter("foo").equals(""));
2. boolean hasParameter =
request.getParameterMap().contains(theParameter);
(which works in Servlet 2.3+)
Question
How can I send user authentication information while
makingURLConnection?
(Servlets)
Answer
You’ll want to use
HttpURLConnection.setRequestProperty and set all the appropriate
headers to HTTP authorization.
Question
How do I convert a numeric IP address like 192.18.97.39
into a hostname like java.sun.com?
(Networking)
Answer
Question
How many methods do u implement if implement the
Serializable Interface?
(Core Java)
Answer
The Serializable interface is just a "marker" interface,
with no methods of its own to implement. Other ’marker’ interfaces
are
java.rmi.Remote
java.util.EventListener
String hostname =InetAddress.getByName("192.18.97.39").getHostName();
posted @
2010-10-25 17:08 Sun River|
編輯 收藏
1.
Question
What is the query used to display all tables names in
SQL Server (Query analyzer)?
(JDBC)
Answer
select * from information_schema.tables
Question
What is Externalizable? (Core Java)
Answer
Externalizable is an Interface that extends Serializable
Interface. And sends data into Streams in Compressed Format. It has
two methods, writeExternal(ObjectOuput out) and
readExternal(ObjectInput in).
Question
What modifiers are allowed for methods in an Interface?
Answer
Only public and abstract modifiers are allowed for
methods in interfaces.
Question
How many types of JDBC Drivers are present and what
are they?
(JDBC)
Answer
There are 4 types of JDBC Drivers
Type 1: JDBC-ODBC Bridge Driver
Type 2: Native API Partly Java Driver
Type 3: Network protocol Driver
Type 4: JDBC Net pure Java Driver
Question
What is the difference between ServletContext and
PageContext?
(JSP)
Answer ServletContext: Gives the information about the container
PageContext: Gives the information about the Request.
Question
How to pass information from JSP to included JSP?
Answer Using <%jsp:param> tag.
posted @
2010-10-25 16:07 Sun River|
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tomcat6配置雙向認(rèn)證
1、生成服務(wù)器端證書
keytool -genkey -keyalg RSA -dname "cn=localhost,ou=sango,o=none,l=china,st=beijing,c=cn" -alias server -keypass password -keystore server.jks -storepass password -validity 3650
2、生成客戶端證書
keytool -genkey -keyalg RSA -dname "cn=sango,ou=sango,o=none,l=china,st=beijing,c=cn" -alias custom -storetype PKCS12 -keypass password -keystore custom.p12 -storepass password -validity 3650
客戶端的CN可以是任意值。
3、由于是雙向SSL認(rèn)證，服務(wù)器必須要信任客戶端證書，因此，必須把客戶端證書添加為服務(wù)器的信任認(rèn)證。由于不能直接將PKCS12格式的證書庫導(dǎo)入，我們必須先把客戶端證書導(dǎo)出為一個單獨(dú)的CER文件，使用如下命令，先把客戶端證書導(dǎo)出為一個單獨(dú)的cer文件：
keytool -export -alias custom -file custom.cer -keystore custom.p12 -storepass password -storetype PKCS12 -rfc
然后，添加客戶端證書到服務(wù)器中（將已簽名數(shù)字證書導(dǎo)入密鑰庫）
keytool -import -v -alias custom -file custom.cer -keystore server.jks -storepass password
4、查看證書內(nèi)容
keytool -list -v -keystore server.jks -storepass password
5、配置tomcat service.xml文件
<Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true"
maxThreads="150" scheme="https" secure="true"
clientAuth="true" sslProtocol="TLS"
keystoreFile="D:/server.jks" keystorePass="password"
truststoreFile="D:/server.jks" truststorePass="password"
/>
clientAuth="true"表示雙向認(rèn)證
6、導(dǎo)入客戶端證書到瀏覽器
雙向認(rèn)證需要強(qiáng)制驗(yàn)證客戶端證書。雙擊“custom.p12”即可將證書導(dǎo)入至IE
tomcat6配置單向認(rèn)證
1、生成服務(wù)器端證書
keytool -genkey -keyalg RSA -dname "cn=localhost,ou=sango,o=none,l=china,st=beijing,c=cn" -alias server -keypass password -keystore server.jks -storepass password -validity 3650
2、由于是單向認(rèn)證，沒有必要生成客戶端的證書，直接進(jìn)入配置tomcat service.xml文件
<Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true"
maxThreads="150" scheme="https" secure="true"
clientAuth="false" sslProtocol="TLS"
keystoreFile="D:/server.jks" keystorePass="password"
/>
clientAuth="false"表示單向認(rèn)證，同時去掉truststoreFile="D:/server.jks" truststorePass="password"這2
posted @
2010-05-11 12:12 Sun River|
編輯 收藏---The key thing to know is that IDs identify a specific element and therefore must be unique on the page – you can only use a specific ID once per document. Many browsers do not enforce this rule but it is a basic rule of HTML/XHTML and should be observed. Classes mark elements as members of a group and can be used multiple times, so if you want to define a style which will be applied to multiple elements you should use a class instead.
Notice that an ID's CSS is an HTML element, followed by a "#", and finally ID's name. The end result looks something like "element#idname". Also, be sure to absorb the fact that when an ID is used in HTML, we must use "id=name" instead of "class=name" to reference it!
Why Did They Choose Those Names??
ID = A person's Identification (ID) is unique to one person.
Class = There are many people in a class.
ID for Layout and Uniqueness
Standards specify that any given ID name can only be referenced once within a page or document. From our experience, IDs are most commonly used correctly in CSS layouts. This makes sense because there are usually only one menu per page, one banner, and usually only one content pane.
In Tizag.com CSS Layout Examples we have used IDs for the unique items mentioned above. View the CSS Code for our first layout example. Below are the unique IDs in our code.
Menu - div#menuPane
Content - div#content
Answer: Classes vs IDs
Use IDs when there is only one occurence per page. Use classes when there are one or more occurences per page.
posted @
2010-03-16 10:14 Sun River|
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