template
public class Test {
public static void main(String[] args) {
}
}
initialize array
int[] intArray = new int[10];
char[] charArray = new char[size];
String[] stringArray = {"Sunday", "Monday", "Tuesday"};
Display
System.out.println("");
e.printStackTrace(System.err);
System.currentTimeMillis();
String
Integer.parseInt(String);
Integer.toOctalString(int);
String.toCharArray();
Integer.parseInt( "1100100", 2 );
Integer.toString( 100, 2);
Integer.toBinaryString( 100 );
Loop
for (int i = 0; i < args.length; i++) {
}
Thread
new Thread();
Thread.start();
Thread.getState() == Thread.State.TERMINATED
Thread.join();
Thread.sleep(10);
UTF-16
int cp ; // Unicode code point in Java integer
Character.isLetter( cp ); // safe for non-BMP characters as well as BMP
int n = s.codePointCount(0, s.length()); // n is the number of Unicode characters
Database
Class.forName("oracle.jdbc.OracleDriver");
DriverManager.getConnection(constr,username,password);
Connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
Statement.executeQuery();
ResultSet.getMetaData();
PreparedStatement.addBatch();
PreparedStatement.executeBatch();
SAX
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
SAXParserFactory factory = SAXParserFactory.newInstance();
SAXParser parser = factory.newSAXParser();
parser.parse(InputSource, DefaultHandler);
public void startElement(String namespaceURI,
String localName,
String qName,
Attributes atts) throws SAXException
m_tagstack.push(qName);
public void endElement(String namespaceURI,
String localName,
String qName) throws SAXException
m_tagstack.pop();
public void characters(char[] ch, int start, int length)
throws SAXException
StringBuffer.append(new String(ch, start, length));
Bit
public class BitTest {
static final int AGE = 1;
static final int ADDRESS = 2;
static final int SEX = 4;
static final int OTHERS = 8;
public static void main(String[] args) {
int judge = 0;
judge = judge | AGE;
judge = judge | ADDRESS;
if ((judge & AGE) == AGE) {
if ((judge & ADDRESS) == ADDRESS) {
System.out.println("Your age and address is OK");
} else {
System.out.println("Your address is NG");
}
} else {
System.out.println("Your age is NG");
}
}
}