sqlrcursor.java

适合于Unix/Linux下的一个持久数据库连接池

// Copyright (c) 2001  David Muse
// See the file COPYING for more information.
package com.firstworks.sqlrelay;

public class SQLRCursor {

	static {
		System.loadLibrary("SQLRCursor");
	}

	public SQLRCursor(SQLRConnection con) {
		connection=con;
		cursor=alloc(con.connection);
	}
	public native void	delete();


	/** Sets the number of rows of the result set
	 *  to buffer at a time.  0 (the default)
	 *  means buffer the entire result set.  */
	public native void	setResultSetBufferSize(long rows);
	/** Returns the number of result set rows that 
	 *  will be buffered at a time or 0 for the
	 *  entire result set.  */
	public native long	getResultSetBufferSize();


	/** Tells the server not to send any column
	 *  info (names, types, sizes).  If you don't
	 *  need that info, you should call this
	 *  method to improve performance.  */
	public native void	dontGetColumnInfo();
	/** Tells the server to send column info.  */
	public native void	getColumnInfo();


	/** Columns names are returned in the same
	 *  case as they are defined in the database.
	 *  This is the default. */
	public native void	mixedCaseColumnNames();
	/** Columns names are converted to upper case. */
	public native void	upperCaseColumnNames();
	/** Columns names are converted to lower case. */
	public native void	lowerCaseColumnNames();

	/** Sets query caching on.  Future queries
	 *  will be cached to the file "filename".
	 * 
	 *  A default time-to-live of 10 minutes is
	 *  also set.
	 * 
	 *  Note that once cacheToFile() is called,
	 *  the result sets of all future queries will
	 *  be cached to that file until another call 
	 *  to cacheToFile() changes which file to
	 *  cache to or a call to cacheOff() turns off
	 *  caching.  */
	public native void	cacheToFile(String filename);
	/** Sets the time-to-live for cached result
	 *  sets. The sqlr-cachemanger will remove each 
	 *  cached result set "ttl" seconds after it's 
	 *  created, provided it's scanning the directory
	 *  containing the cache files.  */
	public native void	setCacheTtl(int ttl);
	/** Returns the name of the file containing the
	 *  cached result set.  */
	public native String	getCacheFileName();
	/** Sets query caching off.  */
	public native void	cacheOff();


	/** Sends "query" and gets a result set.  */
	public native boolean	sendQuery(String query);
	/** Sends the query in file "path"/"filename" 
	 *  and gets a result set.  */
	public native boolean	sendQuery(String query, int length);
	/** Sends "query" with length "length" and gets
	*  a result set. This method must be used if
	*  the query contains binary data. */
	public native boolean	sendFileQuery(String path, String filename); 


	/** Prepare to execute "query".  */
	public native void	prepareQuery(String query);
	/** Prepare to execute the contents 
	 *  of "path"/"filename".  Returns 0 if the
	 *  file couldn't be opened.  */
	public native void	prepareQuery(String query, int length);
	/** Prepare to execute "query" with length 
	 * "length".  This method must be used if the
	 * query contains binary data. */
	public native boolean	prepareFileQuery(String path, String filename);

	/** Clear all bind variables.  */
	public native void	clearBinds();

	/** Define a substitution variable.  */
	public native void	substitution(String variable, String value);
	/** Define a substitution variable.  */
	public native void	substitution(String variable, long value);
	/** Define a substitution variable.  */
	public native void	substitution(String variable, double value, 
					int precision, int scale);

	/** Parses the previously prepared query,
	 *  counts the number of bind variables defined
	 *  in it and returns that number. */
	public native short	countBindVariables();

	/** Define an input bind variable.  */
	public native void	inputBind(String variable, String value);
	/** Define an input bind variable.  */
	public native void	inputBind(String variable, long value);
	/** Define an input bind variable.  */
	public native void	inputBind(String variable, double value, 
					int precision, int scale);
	/** Define an input bind variable.  */
	public native void	inputBindBlob(String variable, byte[] value, 
								long size);
	/** Define an input bind variable.  */
	public native void	inputBindClob(String variable, String value, 
								long size);
	/** Define a string output bind variable.  */
	public native void	defineOutputBindString(String variable, 
							int bufferlength);
	/** Define an integer output bind variable.  */
	public native void	defineOutputBindInteger(String variable);
	/** Define a double precision floating point output bind variable.  */
	public native void	defineOutputBindDouble(String variable);
	/** Define an output bind variable.  */
	public native void	defineOutputBindBlob(String variable);
	/** Define an output bind variable.  */
	public native void	defineOutputBindClob(String variable);
	/** Define an output bind variable.  */
	public native void	defineOutputBindCursor(String variable);

	/** Define an array of substitution variables.  */
	public native void	substitutions(String[] variables, 
							String[] values);

	/** Define an array of substitution variables.  */
	public native void	substitutions(String[] variables, 
							long[] values);

	/** Define an array of substitution variables.  */
	public native void	substitutions(String[] variables, 
					double[] values,
					int[] precisions, int[] scales);

	/** Define an array of input bind variables.  */
	public native void	inputBinds(String[] variables, String[] values);

	/** Define an array of input bind variables.  */
	public native void	inputBinds(String[] variables, long[] values);

	/** Define an array of input bind variables.  */
	public native void	inputBinds(String[] variables, 
					double[] values, 
					int[] precisions, int[] scales);

	/** If you are binding to any variables that 
	 *  might not actually be in your query, call 
	 *  this to ensure that the database won't try 
	 *  to bind them unless they really are in the 
	 *  query.  There is a performance penalty for
	 *  calling this method.  */
	public native void	validateBinds();

	/** Returns true if "variable" was a valid
	 *  bind variable of the query  */
	public native boolean	validBind(String variable);

	/** Execute the query that was previously 
	 *  prepared and bound.  */
	public native boolean	executeQuery();

	/** Fetch from a cursor that was returned as
	 *  an output bind variable.  */
	public native boolean	fetchFromBindCursor();

	/** Get the value stored in a previously
	 *  defined output bind variable.  */
	public native String	getOutputBindString(String variable);
	/** Get the value stored in a previously
	 *  defined output bind variable.  */
	public native byte[]	getOutputBindBlob(String variable);
	/** Get the value stored in a previously
	 *  defined output bind variable.  */
	public native String	getOutputBindClob(String variable);
	/** Get the length of the value stored in a
	 *  previously defined output bind variable.  */
	public native byte[]	getOutputBindAsByteArray(String variable);
	/** Get the value stored in a previously
	 *  defined output bind variable as a long
	 *  integer. */
	public native long	getOutputBindInteger(String variable);
	/** Get the value stored in a previously
	 *  defined output bind variable as a double
	 *  precision floating point number. */
	public native double	getOutputBindDouble(String variable);
	/** Get the length of the value stored in a
	 *  previously defined output bind variable.  */
	public native long	getOutputBindLength(String variable);
	/** Get the cursor associated with a
	 *  previously defined output bind variable.  */
	public SQLRCursor	getOutputBindCursor(String variable) {
		SQLRCursor	bindcur=new SQLRCursor(connection);
		bindcur.cursor=getOutputBindCursorInternal(variable);
		return bindcur;
	}


	/** Opens a cached result set.
	 *  Returns 1 on success and 0 on failure.  */
	public native boolean	openCachedResultSet(String filename);