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Created by Fang on March 30, 2012 10:07:25
Last update: March 30, 2012 10:09:08
After a user resets a password, I want to force the user to change the password before she gets access to secured content. This is usually done with a servlet filter. But with Spring MVC, you can also use a HandlerInterceptor . According to Spring JavaDoc: HandlerInterceptor is basically similar to a Servlet 2.3 Filter, but in contrast to the latter it just allows custom pre-processing with the option of prohibiting the execution of the handler itself, and custom post-processing. Filters are more powerful, for example they allow for exchanging the request and response objects that are handed down the chain. Note that a filter gets configured in web.xml, a HandlerInterceptor in the application context. As a basic guideline, fine-grained handler-related preprocessing tasks are candidates...
Created by freyo on August 25, 2011 09:07:40
Last update: August 25, 2011 20:45:43
This is a list of built-in Android permission values: Permission Description Since API Level android.permission.ACCESS_CHECKIN_PROPERTIES Allows read/write access to the "properties" table in the checkin database, to change values that get uploaded. 1 android.permission.ACCESS_COARSE_LOCATION Allows an application to access coarse (e.g., Cell-ID, WiFi) location 1 android.permission.ACCESS_FINE_LOCATION Allows an application to access fine (e.g., GPS) location 1 android.permission.ACCESS_LOCATION_EXTRA_COMMANDS Allows an application to access extra location provider commands 1 android.permission.ACCESS_MOCK_LOCATION Allows an application to create mock location providers for testing 1 android.permission.ACCESS_NETWORK_STATE Allows applications to access information about networks 1 android.permission.ACCESS_SURFACE_FLINGER Allows an application to use SurfaceFlinger's low level features 1 android.permission.ACCESS_WIFI_STATE Allows applications to access information about Wi-Fi networks 1 android.permission.ACCOUNT_MANAGER Allows applications to call into AccountAuthenticators. Only the system can get this permission. 5 android.permission.AUTHENTICATE_ACCOUNTS...
Created by Dr. Xi on June 22, 2011 07:33:45
Last update: June 22, 2011 11:57:54
Demo code for CSV parsing with OpenCSV . Java code:
import java.io.*; import au.com.bytecode.opencs... Test with a simple CSV file: psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,... The parser worked correctly: Line 1 has 11 values: |psmith01| |CLASS2B|... Test with a more complicated CSV file: "psmith01 abc", "CLASS2B " , " Peter... Result: Line 1 has 4 values: |psmith01 abc| |CLASS... The parser: Escaped quote and backslash correctly Ignored spaces before the quotation mark - sometimes (see below) Counted spaces after the right quotation mark till the comma as content, including the right quotation mark (bug). Ignored improperly quoted item - silently (third line) Indeed, the OpenCSV parser has a problem with spaces: Input: "Smith, Jack", "210-345-8888" "Smith, J... Result: Line 1 has 2 values: | Smith, Jack| |210-3......
Created by Dr. Xi on June 22, 2011 09:42:35
Last update: June 22, 2011 11:39:40
Demo code for CSV parsing with Skife CSV . Java code:
import java.io.*; import java.util.*; import... Test with a simple CSV file: psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,... The parser worked correctly: Line 1 has 11 values: |psmith01| |CLASS2B|... Test with a more complicated CSV file: "psmith01 abc", "CLASS2B " , " Peter... Result: Line 1 has 4 values: |psmith01 abc| | CLAS... The parser worked correctly. But notice that it counts the spaces outside of the quotes significant, and doing so consistently. One more test for spaces: "Smith, Jack" , "210-345-8888" "Smith, Jack"... Result: Line 1 has 2 values: | Smith, Jack | | 210... Add a new line in item two: "One", "Two ", "Three" Result: Line 1 has 2 values: |One| | Two| L...
Created by Dr. Xi on June 21, 2011 15:41:51
Last update: June 22, 2011 11:33:36
Demo code for CSV parsing with Apache Commons CSV parser .
Java code:
import java.io.*;
import org.apache.commons.csv...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
Result:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
The parser worked correctly.
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
Result:
Line 1 has 4 values:
|psmith01 abc|
|CLASS...
The third line is invalid input, but throwing a Java IOException is a bit grave. Also, the parser is not able to escape a backslash.
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 2 has 3 values:
|One|
|Two
|
|...
Created by Dr. Xi on June 21, 2011 15:54:00
Last update: June 22, 2011 11:33:09
Demo code for CSV parsing with SuperCSV parser .
Java code:
import java.io.*;
import java.util.List;
imp...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
The parser worked correctly:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
The parser messed up on all three lines:
Line 1 has 5 values:
|psmith01 abc|
|CLASS...
Using two lines input:
"psmith01 abc", "CLASS2B " , " Peter...
It generates an exception:
Line 1 has 5 values:
|psmith01 abc|
|CLASS...
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 2 has 3 values:
|One|
|Two
|
|...
Created by Dr. Xi on June 22, 2011 07:12:02
Last update: June 22, 2011 11:32:02
Demo code for CSV parsing with OstermillerUtils .
Java code:
import java.io.*;
import java.util.List;
imp...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
The parser worked correctly:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
The parser messed up on all three lines:
Line 1 has 6 values:
|psmith01 abc|
| "CLA...
Putting a space before the first quote:
"Smith, Jack","210-345-8888"
It dismissed the quotes:
Line 1 has 3 values:
| "Smith|
| Jack"|
...
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 1 has 2 values:
|One|
| "Two|
...
Created by alfa on June 07, 2011 11:34:26
Last update: June 07, 2011 11:36:37
This is an example that uses dynamic proxies to trace method calls (in logging) and print out elapsed times for them. Because dynamic proxies can only be generated for interfaces, the service classes must be implemented with interface-implementation pairs. Create services A and B. A.java :
public interface A { public void service1()... AImpl.java : import java.util.Random; public class AImpl... B.java : public interface B { public void service1()... BImpl.java : public class BImpl implements B { public vo... The call trace proxy: import java.lang.reflect.*; class TraceProx... The performance proxy: import java.lang.reflect.*; class Performan... The service factory: import java.lang.reflect.*; public class Se... The test class: public class Test { public static void main... The output: Entering AImpl.service1 Entering BImpl.service1... The above example has no information...
Created by alfa on June 03, 2011 12:36:14
Last update: June 03, 2011 12:36:14
Thread local storage is typically used to associate state with a thread (e.g., a user ID or Transaction ID). This example, coming from Java API doc , assigns a unique id to each thread that calls getCurrentThreadId() . The actual usage is demonstrated with the Java concurrency package.
import java.util.concurrent.Future;
import java...
Created by alfa on May 27, 2011 11:19:29
Last update: May 31, 2011 07:56:26
This is a utility to convert a string value to one of the primitive type values. It is useful in Java reflection code where the value comes in as a string (e.g., from XML parsing), and the type of the value cannot be decided until runtime.
import java.util.*;
import java.lang.reflect.*;...
Note: This method can be extended to convert string to more complex types by writing a converter for the destination type. For example, to convert string to date:
public class DateConverter {
public static ...
Usage:
Date d = (Date) ConvertUtil.convert("10/12/2010", ...
