I create this code for get column name in sql databases. But now I ant to modify above code for get all table data with column name. Then get all data and convert to jsonarray and pass. How I modify this code for get all table data with column name.
@Override
public JSONArray getarray(String sheetName) {
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = (Connection) DriverManager.getConnection("jdbc:mysql://localhost/test", "root", "");
con.setAutoCommit(false);
PreparedStatement pstm = null;
Statement stmt = null;
//-----------------------Drop earliye table -------------------------------------------------------------
try {
String sqldrop = "select COLUMN_NAME from information_schema.COLUMNS where TABLE_NAME='" + sheetName.replaceAll(" ", "_") + "'";
System.out.println(sqldrop);
PreparedStatement mypstmt = con.prepareStatement(sqldrop);
ResultSet resultSet = mypstmt.executeQuery();
JSONArray jsonArray = new JSONArray();
while (resultSet.next()) {
int total_rows = resultSet.getMetaData().getColumnCount();
JSONObject obj = new JSONObject();
for (int i = 0; i < total_rows; i++) {
String columnName = resultSet.getMetaData().getColumnLabel(i + 1).toLowerCase();
Object columnValue = resultSet.getObject(i + 1).toString().replaceAll("_", " ");
// if value in DB is null, then we set it to default value
if (columnValue == null) {
columnValue = "null";
}
/*
Next if block is a hack. In case when in db we have values like price and price1 there's a bug in jdbc -
both this names are getting stored as price in ResulSet. Therefore when we store second column value,
we overwrite original value of price. To avoid that, i simply add 1 to be consistent with DB.
*/
if (obj.has(columnName)) {
columnName += "1";
}
obj.put(columnName, columnValue);
}
jsonArray.put(obj);
}
mypstmt.close();
con.commit();
return jsonArray;
} catch (Exception e) {
System.out.println("There is no exist earlyer databases table!..... :( :( :( **************** " + sheetName.replaceAll(" ", "_"));
}
//----------------------------------------------------------------------------
} catch (ClassNotFoundException e) {
System.out.println(e);
} catch (SQLException ex) {
Logger.getLogger(PassArrayDaoImpl.class.getName()).log(Level.SEVERE, null, ex);
}
System.out.println("%%%%%%%%%%");
return null;
}
My target is get all data with column name and above data pass html page as a json. So if you have any method for get all data with column name is suitable for me.
// code starts here
// This method retrieves all data from a mysql table...
public void retrieveAllData( String host, String user, String pass, String query) {
JTextArea textArea = new JTextArea();
try(
Connection connection = DriverManager.getConnection( host, user, pass )
Statement statement = connection.createStatement()
ResultSet resultSet = statement.executeQuery(query)) {
ResultSetMetaData metaData = resultSet.getMetaData();
int totalColumns = metaData.getColumnCount();
for( int i = 1; i <= totalColumns; i++ ) {
textArea.append( String.format( "%-8s\t", metaData.getColumnName(i) ) );
}
textArea.append( "\n" );
while( resultSet.next() ) {
for( int i = 1; i <= totalColumns; i++ ) {
Object object = resultSet.getObject(i).toString();
textArea.append( String.format("%-8s\t", object) );
}
textArea.append( "\n" );
}
}
}
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