Monday, October 17, 2011

Tự động chụp ảnh màn hình bằng java


import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.File;
import java.net.Socket;

public static void createCapture(String fileName){
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
  Rectangle screenRectangle = new Rectangle(screenSize);
  Robot robot;
try {
robot = new Robot();
BufferedImage image = robot.createScreenCapture(screenRectangle);
try {
ImageIO.write(image, "png", new File(fileName));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (AWTException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}


public static void main(String[] args) {
int delay = 5000;   // delay for 5 sec before start
int period = 1000 * 15 * 60;  // repeat every 15 minute.
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
public void run() {
      String fileName = "filename.png";
        createCapture(fileName);
        }
}, delay, period);
}

Tuesday, October 4, 2011

Seven Java projects that changed the world

Java's open source ecosystem is strong and healthy, one of the primary reasons for our creation of OSCON Java. Over the last decade, several projects have traveled beyond mere adoption and had effects dominating the Java world, into software development in general, and some even further into the daily lives of users.
JUnit

Ported to Java by Kent Beck and Erich Gamma from Beck's work in unit testing in Smalltalk, JUnit has been largely responsible for popularizing test-driven development over the last decade. Many implementations have been created, in .NET, C, Python, Perl and just about every language in popular use.

Eclipse

As Java and its APIs matured in the early 2000s, the Eclipse IDE provided a way for programmers to be productive and negotiate the growing Java ecosystem. Eclipse was also the first major project to use the SWT UI toolkit, providing important competition to Sun's Swing and showing that Java programs can provide a rich native interface. Eclipse has evolved toward a goal of being a universal IDE, and it now provides a rich foundation for platform vendors to integrate with.

Spring

The Spring Framework has played an important role in enabling Java developers to be productive, managing a balance between simplicity and features. Spring gives Java developers a set of services providing commonly used application functionality such as data access and transaction management. As a competitor to Sun's Enterprise Java Beans system, Spring enabled an alternative and simpler path for Java applications, as well as ensuring a healthy competition of ideas in the way Java applications are constructed.

Solr

The Solr server, and the Lucene search engine it encapsulates, has been for many years a simple and practical solution to providing search capabilities to web and enterprise applications. Solr's genius is in providing HTTP access to the powerful and fast Lucene search library, enabling it to become a part of any system, regardless of whether it is implemented in Java or not. More than any other project, Solr has ensured that good search is a checkbox item for modern web applications.

Hudson and Jenkins

Originally developed as Hudson, and now also as Jenkins, this continuous integration tool is a key part of a Java development setup. Jenkins provides automated build and testing of a software project, continuing in the footsteps of JUnit in enabling agile development on the Java platform. While both Hudson and Jenkins persist for now as forks of each other, it doesn't detract from the work of Kohsuke Kawaguchi in creating a world-class continuous integration platform and so enhancing the quality of much Java development.

Hadoop

This Java implementation of the famous MapReduce model is the powerhouse that has enabled most "big data" systems. By lowering the cost of extracting value from large data sets, Hadoop has made practical the personalization and advertising businesses of Facebook and Yahoo, and many other companies. In the same way that Linux enabled large websites to be built on cheap hardware, Hadoop enables large-scale distributed computing by handling failure at the software level. Both Hadoop and the above-mentioned Lucene are the product of the work of Doug Cutting.

Android

Controversy is never that far from Java, whether the custodian be Sun or Oracle. Google's choice to use Java as the programming language for its massively popular Android mobile operating system has led to a renewed interest in the language from whole new communities of software developers. Android programs undergo a further step to convert JVM bytecode to Dalvik bytecode — Dalvik being a virtual machine optimized for mobile devices. Google has been able to leverage Eclipse to provide software developers with a mature development environment for creating Android applications.

Oracle and Google are currently engaged in a lawsuit over a claim that Android infringes on multiple patents held by Oracle. The results of that suit notwithstanding, Android has done much to recruit developers and perpetuate the use of Java in client-side software development.

Nguồn: http://radar.oreilly.com

Friday, September 30, 2011

Xuất ra file unicode

Xuất ra file Unicode trong java


import java.io.FileOutputStream;
import java.io.IOException;

public class Util {
public static void writeUnicode(String filepath, String content){
// Check file exist
File f;
f=new File(filepath);
if(!f.exists()){
try {
f.createNewFile();
System.out.println("New file " + filepath + " has been created ");
} catch (IOException e) {
e.printStackTrace();
}
}
try {
byte[] out = UnicodeUtil.convert(content.getBytes("UTF-16"), "UTF-8");
FileOutputStream fos = new FileOutputStream(filepath);
fos.write(out);
fos.close();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception ex){
ex.printStackTrace();
}
}
}

File UnicodeUtil.java


import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PushbackInputStream;
import java.io.UnsupportedEncodingException;
import java.io.Writer;

public class UnicodeUtil {

public static byte[] convert(byte[] bytes, String encout) throws Exception {
// Workaround for bug that will not be fixed by SUN
// http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4508058
UnicodeInputStream uis = new UnicodeInputStream(new ByteArrayInputStream(bytes), "ASCII");
boolean unicodeOutputReqd = (getBOM(encout) != null) ? true : false;
String enc = uis.getEncoding();
String BOM = getBOM(enc); // get the BOM of the inputstream

if (BOM == null) {
// inputstream looks like ascii...
// create a BOM based on the outputstream
BOM = getBOM(encout);
}
uis.close();

ByteArrayOutputStream out = new ByteArrayOutputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(new ByteArrayInputStream(bytes, uis.getBOMOffset(), bytes.length), enc));
Writer w = new BufferedWriter(new OutputStreamWriter(out, encout));

// dont write a BOM for ascii(out) as the OutputStreamWriter
// will not process it correctly.
if (BOM != null && unicodeOutputReqd) {
w.write(BOM);
}

char[] buffer = new char[4096];
int len;
while ((len = br.read(buffer)) != -1) {
w.write(buffer, 0, len);
}

br.close(); // Close the input.
w.close(); // Flush and close output.
return out.toByteArray();
}

public static String getBOM(String enc) throws UnsupportedEncodingException {
if ("UTF-8".equals(enc)) {
byte[] bom = new byte[3];
bom[0] = (byte) 0xEF;
bom[1] = (byte) 0xBB;
bom[2] = (byte) 0xBF;
return new String(bom, enc);
} else if ("UTF-16BE".equals(enc)) {
byte[] bom = new byte[2];
bom[0] = (byte) 0xFE;
bom[1] = (byte) 0xFF;
return new String(bom, enc);
} else if ("UTF-16LE".equals(enc)) {
byte[] bom = new byte[2];
bom[0] = (byte) 0xFF;
bom[1] = (byte) 0xFE;
return new String(bom, enc);
} else if ("UTF-32BE".equals(enc)) {
byte[] bom = new byte[4];
bom[0] = (byte) 0x00;
bom[1] = (byte) 0x00;
bom[2] = (byte) 0xFE;
bom[3] = (byte) 0xFF;
return new String(bom, enc);
} else if ("UTF-32LE".equals(enc)) {
byte[] bom = new byte[4];
bom[0] = (byte) 0x00;
bom[1] = (byte) 0x00;
bom[2] = (byte) 0xFF;
bom[3] = (byte) 0xFE;
return new String(bom, enc);
} else {
return null;
}

}

public static class UnicodeInputStream extends InputStream {
private PushbackInputStream internalIn;

private boolean isInited = false;

private int BOMOffset = -1;

private String defaultEnc;

private String encoding;

public static final int BOM_SIZE = 4;

public UnicodeInputStream(InputStream in, String defaultEnc) {
internalIn = new PushbackInputStream(in, BOM_SIZE);
this.defaultEnc = defaultEnc;
}

public String getDefaultEncoding() {
return defaultEnc;
}

public String getEncoding() {
if (!isInited) {
try {
init();
} catch (IOException ex) {
IllegalStateException ise = new IllegalStateException("Init method failed.");
ise.initCause(ise);
throw ise;
}
}
return encoding;
}

/**
* Read-ahead four bytes and check for BOM marks. Extra bytes are unread
* back to the stream, only BOM bytes are skipped.
*/
protected void init() throws IOException {
if (isInited)
return;

byte bom[] = new byte[BOM_SIZE];
int n, unread;
n = internalIn.read(bom, 0, bom.length);

if ((bom[0] == (byte) 0x00) && (bom[1] == (byte) 0x00) && (bom[2] == (byte) 0xFE) && (bom[3] == (byte) 0xFF)) {
encoding = "UTF-32BE";
unread = n - 4;
} else if ((bom[0] == (byte) 0xFF) && (bom[1] == (byte) 0xFE) && (bom[2] == (byte) 0x00) && (bom[3] == (byte) 0x00)) {
encoding = "UTF-32LE";
unread = n - 4;
} else if ((bom[0] == (byte) 0xEF) && (bom[1] == (byte) 0xBB) && (bom[2] == (byte) 0xBF)) {
encoding = "UTF-8";
unread = n - 3;
} else if ((bom[0] == (byte) 0xFE) && (bom[1] == (byte) 0xFF)) {
encoding = "UTF-16BE";
unread = n - 2;
} else if ((bom[0] == (byte) 0xFF) && (bom[1] == (byte) 0xFE)) {
encoding = "UTF-16LE";
unread = n - 2;
} else {
// Unicode BOM mark not found, unread all bytes
encoding = defaultEnc;
unread = n;
}
BOMOffset = BOM_SIZE - unread;
if (unread > 0)
internalIn.unread(bom, (n - unread), unread);

isInited = true;
}

public void close() throws IOException {
// init();
isInited = true;
internalIn.close();
}

public int read() throws IOException {
// init();
isInited = true;
return internalIn.read();
}

public int getBOMOffset() {
return BOMOffset;
}
}
}

Nguồn: Internet

Tuesday, September 27, 2011

Common expressions to validate/format a string

Date

/^\d{1,2}(\-|\/|\.)\d{1,2}\1\d{4}$/   mm/dd/yyyy   
US zip code 
  /(^\d{5}$)|(^\d{5}-\d{4}$)/   99999 or 99999-9999
Canadian postal code
 /^\D{1}\d{1}\D{1}\-?\d{1}\D{1}\d{1}$/  Z5Z-5Z5 orZ5Z5Z5
Time   
/^([1-9]|1[0-2]):[0-5]\d(:[0-5]\d(\.\d{1,3})?)?$/ 
HH:MM or HH:MM:SS or HH:MM:SS.mmm
IP Address(no check for alid values (0-255))
/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/ 
999.999.999.999
Dollar Amount
/^((\$\d*)|(\$\d*\.\d{2})|(\d*)|(\d*\.\d{2}))$/ 
100, 100.00, $100 or $100.00
Social Security Number
/^\d{3}\-?\d{2}\-?\d{4}$/   999-99-9999 or999999999
Canadian Social Insurance Number
   /^\d{9}$/ 999999999
/****************************************************************
FILE: RegExpValidate.js

DESCRIPTION: This file contains a library of validation functions
using javascript regular expressions. Library also contains
functions that reformat fields for display or for storage.


VALIDATION FUNCTIONS:

validateEmail - checks format of email address
validateUSPhone - checks format of US phone number
validateNumeric - checks for valid numeric value
validateInteger - checks for valid integer value
validateNotEmpty - checks for blank form field
validateUSZip - checks for valid US zip code
validateUSDate - checks for valid date in US format
validateValue - checks a string against supplied pattern

FORMAT FUNCTIONS:

rightTrim - removes trailing spaces from a string
leftTrim - removes leading spaces from a string
trimAll - removes leading and trailing spaces from a string
removeCurrency - removes currency formatting characters (), $
addCurrency - inserts currency formatting characters
removeCommas - removes comma separators from a number
addCommas - adds comma separators to a number
removeCharacters - removes characters from a string that match
passed pattern


AUTHOR: Karen Gayda

DATE: 03/24/2000
*******************************************************************/

function validateEmail( strValue) {
/************************************************
DESCRIPTION: Validates that a string contains a
valid email pattern.

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.

REMARKS: Accounts for email with country appended
does not validate that email contains valid URL
type (.com, .gov, etc.) or valid country suffix.
*************************************************/
var objRegExp =
/(^[a-z]([a-z_\.]*)@([a-z_\.]*)([.][a-z]{3})$)|(^[a-z]([a-z_\.]*)@
([a-z_\.]*)(\.[a-z]{3})(\.[a-z]{2})*$)/i;

//check for valid email
return objRegExp.test(strValue);
}
function validateUSPhone( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains valid
US phone pattern.
Ex. (999) 999-9999 or (999)999-9999

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.
*************************************************/
var objRegExp = /^\([1-9]\d{2}\)\s?\d{3}\-\d{4}$/;

//check for valid us phone with or without space between
//area code
return objRegExp.test(strValue);
}

function validateNumeric( strValue ) {
/*****************************************************************
DESCRIPTION: Validates that a string contains only valid numbers.

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.
******************************************************************/
var objRegExp = /(^-?\d\d*\.\d*$)|(^-?\d\d*$)|(^-?\.\d\d*$)/;

//check for numeric characters
return objRegExp.test(strValue);
}

function validateInteger( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains only
valid integer number.

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.
**************************************************/
var objRegExp = /(^-?\d\d*$)/;

//check for integer characters
return objRegExp.test(strValue);
}

function validateNotEmpty( strValue ) {
/************************************************
DESCRIPTION: Validates that a string is not all
blank (whitespace) characters.

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.
*************************************************/
var strTemp = strValue;
strTemp = trimAll(strTemp);
if(strTemp.length > 0){
return true;
}
return false;
}
function validateUSZip( strValue ) {
/************************************************
DESCRIPTION: Validates that a string a United
States zip code in 5 digit format or zip+4
format. 99999 or 99999-9999

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.

*************************************************/
var objRegExp = /(^\d{5}$)|(^\d{5}-\d{4}$)/;

//check for valid US Zipcode
return objRegExp.test(strValue);
}

function validateUSDate( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains only
valid dates with 2 digit month, 2 digit day,
4 digit year. Date separator can be ., -, or /.
Uses combination of regular expressions and
string parsing to validate date.
Ex. mm/dd/yyyy or mm-dd-yyyy or mm.dd.yyyy

PARAMETERS:
strValue - String to be tested for validity

RETURNS:
True if valid, otherwise false.

REMARKS:
Avoids some of the limitations of the Date.parse()
method such as the date separator character.
*************************************************/
var objRegExp = /^\d{1,2}(\-|\/|\.)\d{1,2}\1\d{4}$/
//check to see if in correct format
if(!objRegExp.test(strValue))
return false; //doesn't match pattern, bad date
else{
var strSeparator = strValue.substring(2,3)
var arrayDate = strValue.split(strSeparator);
//create a lookup for months not equal to Feb.
var arrayLookup = { '01' : 31,'03' : 31,
'04' : 30,'05' : 31,
'06' : 30,'07' : 31,
'08' : 31,'09' : 30,
'10' : 31,'11' : 30,'12' : 31}
var intDay = parseInt(arrayDate[1],10);

//check if month value and day value agree
if(arrayLookup[arrayDate[0]] != null) {
if(intDay <= arrayLookup[arrayDate[0]] && intDay != 0)
return true; //found in lookup table, good date
}
//check for February (bugfix 20050322)
//bugfix for parseInt kevin
//bugfix biss year O.Jp Voutat
var intMonth = parseInt(arrayDate[0],10);
if (intMonth == 2) {
var intYear = parseInt(arrayDate[2]);
if (intDay > 0 && intDay < 29) {
return true;
}
else if (intDay == 29) {
if ((intYear % 4 == 0) && (intYear % 100 != 0) ||
(intYear % 400 == 0)) {
// year div by 4 and ((not div by 100) or div by 400) ->ok
return true;
}
}
}
}
return false; //any other values, bad date
}
function validateValue( strValue, strMatchPattern ) {
/************************************************
DESCRIPTION: Validates that a string a matches
a valid regular expression value.

PARAMETERS:
strValue - String to be tested for validity
strMatchPattern - String containing a valid
regular expression match pattern.

RETURNS:
True if valid, otherwise false.
*************************************************/
var objRegExp = new RegExp( strMatchPattern);

//check if string matches pattern
return objRegExp.test(strValue);
}


function rightTrim( strValue ) {
/************************************************
DESCRIPTION: Trims trailing whitespace chars.

PARAMETERS:
strValue - String to be trimmed.

RETURNS:
Source string with right whitespaces removed.
*************************************************/
var objRegExp = /^([\w\W]*)(\b\s*)$/;

if(objRegExp.test(strValue)) {
//remove trailing a whitespace characters
strValue = strValue.replace(objRegExp, '$1');
}
return strValue;
}

function leftTrim( strValue ) {
/************************************************
DESCRIPTION: Trims leading whitespace chars.

PARAMETERS:
strValue - String to be trimmed

RETURNS:
Source string with left whitespaces removed.
*************************************************/
var objRegExp = /^(\s*)(\b[\w\W]*)$/;

if(objRegExp.test(strValue)) {
//remove leading a whitespace characters
strValue = strValue.replace(objRegExp, '$2');
}
return strValue;
}

function trimAll( strValue ) {
/************************************************
DESCRIPTION: Removes leading and trailing spaces.

PARAMETERS: Source string from which spaces will
be removed;

RETURNS: Source string with whitespaces removed.
*************************************************/
var objRegExp = /^(\s*)$/;

//check for all spaces
if(objRegExp.test(strValue)) {
strValue = strValue.replace(objRegExp, '');
if( strValue.length == 0)
return strValue;
}

//check for leading & trailing spaces
objRegExp = /^(\s*)([\W\w]*)(\b\s*$)/;
if(objRegExp.test(strValue)) {
//remove leading and trailing whitespace characters
strValue = strValue.replace(objRegExp, '$2');
}
return strValue;
}
PARAMETERS:
strValue - Source string from which currency formatting
will be removed;

RETURNS: Source string with commas removed.
*************************************************/
var objRegExp = /\(/;
var strMinus = '';

//check if negative
if(objRegExp.test(strValue)){
strMinus = '-';
}

objRegExp = /\)|\(|[,]/g;
strValue = strValue.replace(objRegExp,'');
if(strValue.indexOf('$') >= 0){
strValue = strValue.substring(1, strValue.length);
}
return strMinus + strValue;
}

function addCurrency( strValue ) {
/************************************************
DESCRIPTION: Formats a number as currency.

PARAMETERS:
strValue - Source string to be formatted

REMARKS: Assumes number passed is a valid
numeric value in the rounded to 2 decimal
places. If not, returns original value.
*************************************************/
var objRegExp = /-?[0-9]+\.[0-9]{2}$/;

if( objRegExp.test(strValue)) {
objRegExp.compile('^-');
strValue = addCommas(strValue);
if (objRegExp.test(strValue)){
strValue = '(' + strValue.replace(objRegExp,'') + ')';
}
return '$' + strValue;
}
else
return strValue;
}

function removeCommas( strValue ) {
/************************************************
DESCRIPTION: Removes commas from source string.

PARAMETERS:
strValue - Source string from which commas will
be removed;

RETURNS: Source string with commas removed.
*************************************************/
var objRegExp = /,/g; //search for commas globally

//replace all matches with empty strings
return strValue.replace(objRegExp,'');
}

function addCommas( strValue ) {
/************************************************
DESCRIPTION: Inserts commas into numeric string.

PARAMETERS:
strValue - source string containing commas.

RETURNS: String modified with comma grouping if
source was all numeric, otherwise source is
returned.

REMARKS: Used with integers or numbers with
2 or less decimal places.
*************************************************/
var objRegExp = new RegExp('(-?[0-9]+)([0-9]{3})');

//check for match to search criteria
while(objRegExp.test(strValue)) {
//replace original string with first group match,
//a comma, then second group match
strValue = strValue.replace(objRegExp, '$1,$2');
}
return strValue;
}

function removeCharacters( strValue, strMatchPattern ) {
/************************************************
DESCRIPTION: Removes characters from a source string
based upon matches of the supplied pattern.

PARAMETERS:
strValue - source string containing number.

RETURNS: String modified with characters
matching search pattern removed

USAGE: strNoSpaces = removeCharacters( ' sfdf dfd',
'\s*')
*************************************************/
var objRegExp = new RegExp( strMatchPattern, 'gi' );

//replace passed pattern matches with blanks
return strValue.replace(objRegExp,'');
}