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Displaying keyword search results 1 - 10
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 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 April 05, 2011 08:04:37
Last update: April 05, 2011 08:11:37
There's no difference between a Java HTTP client and a Java HTTPS client. Ignore JavaWorld Java Tip 96 , it's way too old. The following code gets an HTTP page as well as an HTTPS page.
import java.io.*;
import java.net.*;
pub...
There's one catch . If you are using the code on a test server with a self-signed certificate, it fails. In that case, I would suggest that you download the certificate from the server and import it to your keystore as a trusted key. You may also need to add a subject alternative name to the certificate if the host name does not match the certificate.
You may also choose to use a custom TrustManager and HostnameVerifier to ignore the certificate verification errors.
Created by Dr. Xi on March 28, 2011 20:51:30
Last update: March 28, 2011 20:53:46
HTTP basic authentication is just Base64 encoded user name and password passed in as the Authorization header. So the following code works:
// encode user name and password
String credent...
However, since JDK 1.2, there's a more Java friendly way:
Authenticator.setDefault(new Authenticator() {
...
Test code:
import java.net.*;
import java.io.*;
pub...
Created by Dr. Xi on October 16, 2008 20:45:40
Last update: March 28, 2011 20:23:22
Java's built-in classes are way too complex/flexible for a simple protocol like HTTP. This is a wrapper to simplify HTTP GET and POST.
import java.io.*;
import java.net.*;
imp...
A simple test:
import java.io.*;
import java.util.*;
...
Created by Dr. Xi on August 03, 2010 16:23:55
Last update: October 22, 2010 15:35:20
According to Java documentation:
The Java compiler and other Java tools can only process files which contain Latin-1 and/or Unicode-encoded (\udddd notation) characters.
This utility converts a utf-8 encoded file to ascii with unicode escape strings for non-ascii characters.
import java.io.*;
/**
* Reads file in U...
It is equivalent to:
native2ascii -encoding utf-8
using the standard Java native2ascii utility.
Created by Dr. Xi on August 03, 2010 16:29:35
Last update: August 03, 2010 16:36:50
This utility converts unicode escape strings in a file to UTF-8 encoded. Suppose you received a properties file with contents like:
# @(#)codepoint_zh_CN.properties 1.4 05/09/27
#...
You can use this utility to convert it to UTF-8 and view or edit.
import java.io.*;
/**
* Reads file with...
This utility is equivalent to:
native2ascii -reverse -encoding utf-8
using the standard Java native2ascii utility.
