com.solarmetric.kodo.impl.jdbc.sql
Class SQLBuffer

java.lang.Object
  |
  +--com.solarmetric.kodo.impl.jdbc.sql.SQLBuffer

All Implemented Interfaces:

Serializable

public final class SQLBuffer

extends Object

implements Serializable

Buffer for SQL statements. A SQLBuffer holds a list of SQLElement objects, which will be concatinated to build a meaningful SQL representation. The SQL that is held in a SQLBuffer is not datastore-agnostic. The SQLElement implementations that are added to the list are arbitrary, but typically values that will not usefully be parameterized by the data store will be added as SQLLiterals, and values that can be parameterized will be added as SQLValues. This allows the runtime envionment to be able to re-use existing PreparedStatement objects with a high cache hit ratio, while still maintaining meaningful parameterization of the SQL statements.

Raw SQL suitable for use in a Statement can always be accessed via the getStatementSQL method.

Example usage:

	SQLBuffer query = new SQLBuffer ();
	query.appendLiteral ("SELECT * FROM MYTABLE ");

	SQLBuffer whereClause = new SQLBuffer ();
	whereClause.appendLiteral ("WHERE ID = ");
	whereClause.appendValue (new SQLValue (new Integer (10), dict, type));

	query.appendBuffer (whereClause);

	String selectSQL = query.getStatementSQL ();
	

This class is not thread-safe.

Since:

2.4

See Also:

SQLValue, SQLLiteral, SQLElement, Serialized Form

Constructor Summary

SQLBuffer()
Constructor.

SQLBuffer(SQLBuffer toCopy)
Constructor.

SQLBuffer(String rawSQL)
Constructor.

Method Summary

SQLBuffer	appendBuffer(SQLBuffer buffer) Append all elements of the specified SQLBuffer (shallowly) to this one.
SQLBuffer	appendLiteral(SQLLiteral literal) Append some raw, un-preparable SQL to the statement.
SQLBuffer	appendLiteral(String rawSQL) Append some raw, un-preparable SQL to the statement.
SQLBuffer	appendValue(SQLValue element) Append a SQLValue.
Object	clone() Perform a shallow clone of this SQL Buffer.
boolean	equals(Object other)
String	getPreparedStatementSQL() Obtain the String key can can be used to look up an equivalent PreparedStatement in a Map of String:PreparedStatement.
String	getStatementSQL() Obtain the raw SQL that can be used in a Statement.
int	hashCode()
Iterator	iterator() Obtain an interator the the list of SQL Statements.
int	setParameters(PreparedStatement ps) Populate the parameters of an existing PreparedStatement with values from this SQLBuffer.
int	setParameters(PreparedStatement ps, int startIndex) Populate the parameters of an existing PreparedStatement with values from this SQLBuffer.
int	size() Returns the number of SQLElements contained in this buffer.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SQLBuffer

public SQLBuffer()

Constructor. Create an empty SQLBuffer.

SQLBuffer

public SQLBuffer(String rawSQL)

Constructor. Create a SQLBuffer with the first element being the specified raw SQL String.

SQLBuffer

public SQLBuffer(SQLBuffer toCopy)

Constructor. Create a new SQLBuffer using a shallow clone of the specified buffer.

Method Detail

clone

public Object clone()

Perform a shallow clone of this SQL Buffer.

Overrides:

clone in class Object

appendLiteral

public SQLBuffer appendLiteral(String rawSQL)

Append some raw, un-preparable SQL to the statement.

appendLiteral

public SQLBuffer appendLiteral(SQLLiteral literal)

Append some raw, un-preparable SQL to the statement.

appendValue

public SQLBuffer appendValue(SQLValue element)

Append a SQLValue.

appendBuffer

public SQLBuffer appendBuffer(SQLBuffer buffer)

Append all elements of the specified SQLBuffer (shallowly) to this one.

getPreparedStatementSQL

public String getPreparedStatementSQL()

Obtain the String key can can be used to look up an equivalent PreparedStatement in a Map of String:PreparedStatement.

getStatementSQL

public String getStatementSQL()

Obtain the raw SQL that can be used in a Statement.

setParameters

public int setParameters(PreparedStatement ps)
                  throws SQLException

Populate the parameters of an existing PreparedStatement with values from this SQLBuffer.

setParameters

public int setParameters(PreparedStatement ps,
                         int startIndex)
                  throws SQLException

Populate the parameters of an existing PreparedStatement with values from this SQLBuffer.

size

public int size()

Returns the number of SQLElements contained in this buffer.

iterator

public Iterator iterator()

Obtain an interator the the list of SQL Statements.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object other)

Overrides:

equals in class Object