de.ipcon.db.oql

Class ExplainNode

java.lang.Object

de.ipcon.db.oql.ParseTreeNode

de.ipcon.db.oql.ExplainNode

public class ExplainNode
extends ParseTreeNode

This class wraps the PostgreSQL EXPLAIN node and optional parameters that can be used as a prefix for a query to retrieve explanations of an OQL query without the need to directly inspect the generated SQL query. For more information on PostgreSQL EXPLAIN, refer to the PostgreSQL documentation.

Method Summary

Modifier and Type	Method and Description
java.lang.String	debugString() returns a String representation of this node including it's children
de.ipcon.db.oql.ExpressionResultType	getExpressionResultType()
java.lang.Class<?>	getResultClass() Calculates the resulting Java class of this node, which is used if it is part of the select expression.
ValueType	getType()
static ExplainNode	parse(Parser parser) Parses explain options and returns an explain node.
void	renderSQL(java.lang.StringBuilder query, java.lang.Object[] oqlArgs, java.util.List sqlArgs) Renders this node into a StringBuilder as SQL statement, copying arguments from oqlArgs to sqlArgs if needed.

Methods inherited from class de.ipcon.db.oql.ParseTreeNode

addChild, appendComments, appendDebugString, getChild, getChildCount, getOperatorPrecedence, getParent, getToken, hasType, isLeaf, isRoot, removeChild, setOwnType, setParent, setToken, setType, setType, setType, setTypeFromChildren, setTypeFromParent, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

parse

public static ExplainNode parse(Parser parser)
                         throws OQLSyntaxException

Parses explain options and returns an explain node. Will return null if the current token is not the explain keyword.

Parameters:

parser - the parser

Returns:

the explainnode or null, if the current token is not the explain keyword

Throws:

OQLSyntaxException - if the explains are not correct

debugString

public java.lang.String debugString()

Description copied from class: ParseTreeNode

returns a String representation of this node including it's children

Overrides:

debugString in class ParseTreeNode

renderSQL

public void renderSQL(java.lang.StringBuilder query,
                      java.lang.Object[] oqlArgs,
                      java.util.List sqlArgs)

Description copied from class: ParseTreeNode

Renders this node into a StringBuilder as SQL statement, copying arguments from oqlArgs to sqlArgs if needed.

Overrides:

renderSQL in class ParseTreeNode

getExpressionResultType

public de.ipcon.db.oql.ExpressionResultType getExpressionResultType()

Overrides:

getExpressionResultType in class ParseTreeNode

getType

public ValueType getType()

Overrides:

getType in class ParseTreeNode

getResultClass

public java.lang.Class<?> getResultClass()

Description copied from class: ParseTreeNode

Calculates the resulting Java class of this node, which is used if it is part of the select expression. It will return the default Java class of the current type or java.lang.Object if ParseTreeNode.type is null.

Overrides:

getResultClass in class ParseTreeNode

Returns:

A non-null Java class of this node, possibly defaulting to java.lang.Object if the type is not known or not applicable.