Notes by Dr. Xi
Displaying keyword search results 1 - 10
Created by Dr. Xi on May 02, 2011 15:59:37
Last update: February 25, 2012 09:16:37
This code snippet gets the default keystore used by the Java keytool and displays the list of aliases along with the key type (certificate or private key).
import java.io.File;
import java.io.FileInputSt...
The default keystore used by the above code is: $HOME/.keystore .
Created by Dr. Xi on January 06, 2012 14:02:09
Last update: January 06, 2012 14:02:09
In Java, the OS temporary directory is identified by the system property java.io.tmpdir :
public class TmpDir {
public static void ma...
Created by Dr. Xi on November 11, 2011 10:05:22
Last update: November 11, 2011 10:12:01
This is an HTML image tag filter using Java regex. It takes a string, finds the img tags, replaces the src attribute with one provided by the filter, then adds a class name to the class attribute.
import java.util.regex.*;
import java.io.*;
...
Test file:
<div id="HTML snippet">
<img src="img/big/txt-m...
Created by Dr. Xi on July 13, 2011 16:18:05
Last update: July 13, 2011 16:18:05
The goal is to read a file like this:
for (String line: textFileReader) {
// do s...
This is the code:
import java.io.*;
import java.util.Iterator;
...
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 Dr. Xi on June 16, 2011 14:23:44
Last update: June 16, 2011 14:25:04
This example shows how a service implementation can be loaded with a URLClassLoader .
The files.
HelloService.java :
public interface HelloService {
public void...
HelloServiceImpl.java :
public class HelloServiceImpl implements HelloServ...
ServiceFactory.java uses URLClassLoader to load the service implementation:
import java.io.*;
import java.net.*;
pub...
Test.java :
import java.io.*;
import java.net.*;
pub...
Create a runnable client jar:
C:\>jar -cfe client.jar Test Test.class ServiceFac...
Create a service jar:
jar -cf service.jar HelloServiceImpl.class
Test:
C:\>java -jar client.jar
Class Loader: java.net...
Extra Note: : JDK7 added a method URLClassLoader.close() , so that a URLClassLoader can be discarded, and a new one created to load a new implementation.
