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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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package java.sql;

import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;

An exception that provides information on a database access
error or other errors.
Each SQLException provides several kinds of information:

  
 a string describing the error.  This is used as the Java Exception
      message, available via the method getMessage.
  
 a "SQLstate" string, which follows either the XOPEN SQLstate conventions
       or the SQL:2003 conventions.
      The values of the SQLState string are described in the appropriate spec.
      The DatabaseMetaData method getSQLStateType
      can be used to discover whether the driver returns the XOPEN type or
      the SQL:2003 type.
  
 an integer error code that is specific to each vendor.  Normally this will
      be the actual error code returned by the underlying database.
  
 a chain to a next Exception.  This can be used to provide additional
      error information.
  
 the causal relationship, if any for this SQLException.

Since:
1.1/**
 * <P>An exception that provides information on a database access
 * error or other errors.
 *
 * <P>Each <code>SQLException</code> provides several kinds of information:
 * <UL>
 *   <LI> a string describing the error.  This is used as the Java Exception
 *       message, available via the method <code>getMessage</code>.
 *   <LI> a "SQLstate" string, which follows either the XOPEN SQLstate conventions
 *        or the SQL:2003 conventions.
 *       The values of the SQLState string are described in the appropriate spec.
 *       The <code>DatabaseMetaData</code> method <code>getSQLStateType</code>
 *       can be used to discover whether the driver returns the XOPEN type or
 *       the SQL:2003 type.
 *   <LI> an integer error code that is specific to each vendor.  Normally this will
 *       be the actual error code returned by the underlying database.
 *   <LI> a chain to a next Exception.  This can be used to provide additional
 *       error information.
 *   <LI> the causal relationship, if any for this <code>SQLException</code>.
 * </UL>
 *
 * @since 1.1
 */
public class SQLException extends java.lang.Exception
                          implements Iterable<Throwable> {

    
 Constructs a SQLException object with a given
reason, SQLState  and
vendorCode.
The cause is not initialized, and may subsequently be initialized by a call to the Throwable.initCause(Throwable) method. 
Params:
reason – a description of the exception
SQLState – an XOPEN or SQL:2003 code identifying the exception
vendorCode – a database vendor-specific exception code/**
     *  Constructs a <code>SQLException</code> object with a given
     * <code>reason</code>, <code>SQLState</code>  and
     * <code>vendorCode</code>.
     *
     * The <code>cause</code> is not initialized, and may subsequently be
     * initialized by a call to the
     * {@link Throwable#initCause(java.lang.Throwable)} method.
     *
     * @param reason a description of the exception
     * @param SQLState an XOPEN or SQL:2003 code identifying the exception
     * @param vendorCode a database vendor-specific exception code
     */
    public SQLException(String reason, String SQLState, int vendorCode) {
        super(reason);
        this.SQLState = SQLState;
        this.vendorCode = vendorCode;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                DriverManager.println("SQLState(" + SQLState +
                                                ") vendor code(" + vendorCode + ")");
                printStackTrace(DriverManager.getLogWriter());
            }
        }
    }


    
Constructs a SQLException object with a given
reason and SQLState.
The cause is not initialized, and may subsequently be initialized by a call to the Throwable.initCause(Throwable) method. The vendor code is initialized to 0. 
Params:
reason – a description of the exception
SQLState – an XOPEN or SQL:2003 code identifying the exception/**
     * Constructs a <code>SQLException</code> object with a given
     * <code>reason</code> and <code>SQLState</code>.
     *
     * The <code>cause</code> is not initialized, and may subsequently be
     * initialized by a call to the
     * {@link Throwable#initCause(java.lang.Throwable)} method. The vendor code
     * is initialized to 0.
     *
     * @param reason a description of the exception
     * @param SQLState an XOPEN or SQL:2003 code identifying the exception
     */
    public SQLException(String reason, String SQLState) {
        super(reason);
        this.SQLState = SQLState;
        this.vendorCode = 0;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                printStackTrace(DriverManager.getLogWriter());
                DriverManager.println("SQLException: SQLState(" + SQLState + ")");
            }
        }
    }

    
 Constructs a SQLException object with a given
reason. The  SQLState  is initialized to
null and the vendor code is initialized to 0.
The cause is not initialized, and may subsequently be initialized by a call to the Throwable.initCause(Throwable) method. 
Params:
reason – a description of the exception/**
     *  Constructs a <code>SQLException</code> object with a given
     * <code>reason</code>. The  <code>SQLState</code>  is initialized to
     * <code>null</code> and the vendor code is initialized to 0.
     *
     * The <code>cause</code> is not initialized, and may subsequently be
     * initialized by a call to the
     * {@link Throwable#initCause(java.lang.Throwable)} method.
     *
     * @param reason a description of the exception
     */
    public SQLException(String reason) {
        super(reason);
        this.SQLState = null;
        this.vendorCode = 0;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                printStackTrace(DriverManager.getLogWriter());
            }
        }
    }

    
Constructs a SQLException object.
The reason, SQLState are initialized
to null and the vendor code is initialized to 0.
The cause is not initialized, and may subsequently be initialized by a call to the Throwable.initCause(Throwable) method. /**
     * Constructs a <code>SQLException</code> object.
     * The <code>reason</code>, <code>SQLState</code> are initialized
     * to <code>null</code> and the vendor code is initialized to 0.
     *
     * The <code>cause</code> is not initialized, and may subsequently be
     * initialized by a call to the
     * {@link Throwable#initCause(java.lang.Throwable)} method.
     *
     */
    public SQLException() {
        super();
        this.SQLState = null;
        this.vendorCode = 0;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                printStackTrace(DriverManager.getLogWriter());
            }
        }
    }

    
 Constructs a SQLException object with a given
cause.
The SQLState is initialized
to null and the vendor code is initialized to 0.
The reason  is initialized to null if
cause==null or to cause.toString() if
cause!=null.
Params:
cause – the underlying reason for this SQLException
(which is saved for later retrieval by the getCause() method);
may be null indicating the cause is non-existent or unknown.
Since:
1.6/**
     *  Constructs a <code>SQLException</code> object with a given
     * <code>cause</code>.
     * The <code>SQLState</code> is initialized
     * to <code>null</code> and the vendor code is initialized to 0.
     * The <code>reason</code>  is initialized to <code>null</code> if
     * <code>cause==null</code> or to <code>cause.toString()</code> if
     * <code>cause!=null</code>.
     *
     * @param cause the underlying reason for this <code>SQLException</code>
     * (which is saved for later retrieval by the <code>getCause()</code> method);
     * may be null indicating the cause is non-existent or unknown.
     * @since 1.6
     */
    public SQLException(Throwable cause) {
        super(cause);

        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                printStackTrace(DriverManager.getLogWriter());
            }
        }
    }

    
Constructs a SQLException object with a given
reason and  cause.
The SQLState is  initialized to null
and the vendor code is initialized to 0.
Params:
reason – a description of the exception.
cause – the underlying reason for this SQLException
(which is saved for later retrieval by the getCause() method);
may be null indicating the cause is non-existent or unknown.
Since:
1.6/**
     * Constructs a <code>SQLException</code> object with a given
     * <code>reason</code> and  <code>cause</code>.
     * The <code>SQLState</code> is  initialized to <code>null</code>
     * and the vendor code is initialized to 0.
     *
     * @param reason a description of the exception.
     * @param cause the underlying reason for this <code>SQLException</code>
     * (which is saved for later retrieval by the <code>getCause()</code> method);
     * may be null indicating the cause is non-existent or unknown.
     * @since 1.6
     */
    public SQLException(String reason, Throwable cause) {
        super(reason,cause);

        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                    printStackTrace(DriverManager.getLogWriter());
            }
        }
    }

    
Constructs a SQLException object with a given
reason, SQLState and  cause.
The vendor code is initialized to 0.
Params:
reason – a description of the exception.
sqlState – an XOPEN or SQL:2003 code identifying the exception
cause – the underlying reason for this SQLException
(which is saved for later retrieval by the
getCause() method); may be null indicating
    the cause is non-existent or unknown.
Since:
1.6/**
     * Constructs a <code>SQLException</code> object with a given
     * <code>reason</code>, <code>SQLState</code> and  <code>cause</code>.
     * The vendor code is initialized to 0.
     *
     * @param reason a description of the exception.
     * @param sqlState an XOPEN or SQL:2003 code identifying the exception
     * @param cause the underlying reason for this <code>SQLException</code>
     * (which is saved for later retrieval by the
     * <code>getCause()</code> method); may be null indicating
     *     the cause is non-existent or unknown.
     * @since 1.6
     */
    public SQLException(String reason, String sqlState, Throwable cause) {
        super(reason,cause);

        this.SQLState = sqlState;
        this.vendorCode = 0;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                printStackTrace(DriverManager.getLogWriter());
                DriverManager.println("SQLState(" + SQLState + ")");
            }
        }
    }

    
Constructs a SQLException object with a given
reason, SQLState, vendorCode
and  cause.
Params:
reason – a description of the exception
sqlState – an XOPEN or SQL:2003 code identifying the exception
vendorCode – a database vendor-specific exception code
cause – the underlying reason for this SQLException
(which is saved for later retrieval by the getCause() method);
may be null indicating the cause is non-existent or unknown.
Since:
1.6/**
     * Constructs a <code>SQLException</code> object with a given
     * <code>reason</code>, <code>SQLState</code>, <code>vendorCode</code>
     * and  <code>cause</code>.
     *
     * @param reason a description of the exception
     * @param sqlState an XOPEN or SQL:2003 code identifying the exception
     * @param vendorCode a database vendor-specific exception code
     * @param cause the underlying reason for this <code>SQLException</code>
     * (which is saved for later retrieval by the <code>getCause()</code> method);
     * may be null indicating the cause is non-existent or unknown.
     * @since 1.6
     */
    public SQLException(String reason, String sqlState, int vendorCode, Throwable cause) {
        super(reason,cause);

        this.SQLState = sqlState;
        this.vendorCode = vendorCode;
        if (!(this instanceof SQLWarning)) {
            if (DriverManager.getLogWriter() != null) {
                DriverManager.println("SQLState(" + SQLState +
                                                ") vendor code(" + vendorCode + ")");
                printStackTrace(DriverManager.getLogWriter());
            }
        }
    }

    
Retrieves the SQLState for this SQLException object.
Returns:
the SQLState value/**
     * Retrieves the SQLState for this <code>SQLException</code> object.
     *
     * @return the SQLState value
     */
    public String getSQLState() {
        return (SQLState);
    }

    
Retrieves the vendor-specific exception code
for this SQLException object.
Returns:
the vendor's error code/**
     * Retrieves the vendor-specific exception code
     * for this <code>SQLException</code> object.
     *
     * @return the vendor's error code
     */
    public int getErrorCode() {
        return (vendorCode);
    }

    
Retrieves the exception chained to this
SQLException object by setNextException(SQLException ex).
See Also:
setNextException
Returns:
the next SQLException object in the chain;
        null if there are none/**
     * Retrieves the exception chained to this
     * <code>SQLException</code> object by setNextException(SQLException ex).
     *
     * @return the next <code>SQLException</code> object in the chain;
     *         <code>null</code> if there are none
     * @see #setNextException
     */
    public SQLException getNextException() {
        return (next);
    }

    
Adds an SQLException object to the end of the chain.
Params:
ex – the new exception that will be added to the end of
           the SQLException chain
See Also:
getNextException/**
     * Adds an <code>SQLException</code> object to the end of the chain.
     *
     * @param ex the new exception that will be added to the end of
     *            the <code>SQLException</code> chain
     * @see #getNextException
     */
    public void setNextException(SQLException ex) {

        SQLException current = this;
        for(;;) {
            SQLException next=current.next;
            if (next != null) {
                current = next;
                continue;
            }

            if (nextUpdater.compareAndSet(current,null,ex)) {
                return;
            }
            current=current.next;
        }
    }

    
Returns an iterator over the chained SQLExceptions.  The iterator will
be used to iterate over each SQLException and its underlying cause
(if any).
Returns:
an iterator over the chained SQLExceptions and causes in the proper
order
Since:
1.6/**
     * Returns an iterator over the chained SQLExceptions.  The iterator will
     * be used to iterate over each SQLException and its underlying cause
     * (if any).
     *
     * @return an iterator over the chained SQLExceptions and causes in the proper
     * order
     *
     * @since 1.6
     */
    public Iterator<Throwable> iterator() {

       return new Iterator<Throwable>() {

           SQLException firstException = SQLException.this;
           SQLException nextException = firstException.getNextException();
           Throwable cause = firstException.getCause();

           public boolean hasNext() {
               if(firstException != null || nextException != null || cause != null)
                   return true;
               return false;
           }

           public Throwable next() {
               Throwable throwable = null;
               if(firstException != null){
                   throwable = firstException;
                   firstException = null;
               }
               else if(cause != null){
                   throwable = cause;
                   cause = cause.getCause();
               }
               else if(nextException != null){
                   throwable = nextException;
                   cause = nextException.getCause();
                   nextException = nextException.getNextException();
               }
               else
                   throw new NoSuchElementException();
               return throwable;
           }

           public void remove() {
               throw new UnsupportedOperationException();
           }

       };

    }

    
@serial
/**
         * @serial
         */
    private String SQLState;

        
@serial
/**
         * @serial
         */
    private int vendorCode;

        
@serial
/**
         * @serial
         */
    private volatile SQLException next;

    private static final AtomicReferenceFieldUpdater<SQLException,SQLException> nextUpdater =
            AtomicReferenceFieldUpdater.newUpdater(SQLException.class,SQLException.class,"next");

    private static final long serialVersionUID = 2135244094396331484L;
}