com.healthmarketscience.sqlbuilder

Class BaseCaseStatement<ThisType extends BaseCaseStatement<ThisType>>

java.lang.Object

com.healthmarketscience.common.util.AppendeeObject

com.healthmarketscience.sqlbuilder.SqlObject

com.healthmarketscience.sqlbuilder.Expression

com.healthmarketscience.sqlbuilder.BaseCaseStatement<ThisType>

All Implemented Interfaces:

Appendee, Verifiable<ThisType>

Direct Known Subclasses:

CaseStatement, SimpleCaseStatement

public abstract class BaseCaseStatement<ThisType extends BaseCaseStatement<ThisType>>
extends Expression
implements Verifiable<ThisType>

Common base class for "CASE ... END" clauses

Author:

James Ahlborn

Field Summary

Fields inherited from class com.healthmarketscience.sqlbuilder.Expression

EMPTY

Fields inherited from class com.healthmarketscience.sqlbuilder.SqlObject

ALL_SYMBOL, NULL_VALUE, QUESTION_MARK

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BaseCaseStatement(SqlObject operand)

Method Summary

Modifier and Type	Method and Description
ThisType	addCustomWhen(Object test, Object result) Adds a "WHEN" clause to the "CASE" statement.
ThisType	addElse(Object result) Adds an "ELSE" clause to the "CASE" statement.
ThisType	addElseNull() Adds an "ELSE NULL" clause to the "CASE" statement.
protected void	appendCustomIfNotNull(AppendableExt app, SqlObject obj) Appends the given custom clause to the given AppendableExt, handling null and enclosing parens.
protected void	appendNestedClauses(AppendableExt app, SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses) Appends the given nested clauses to the given AppendableExt, handling empty nested clauses and enclosing parens.
void	appendTo(AppendableExt app) Appends this object to the given AppendableExt.
protected static boolean	areEmpty(SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses) Determines if any of the given clauses are non-empty.
protected void	closeParen(AppendableExt app) Appends a close parenthesis to the given AppendableExt if disableParens is true, otherwise does nothing.
protected void	collectSchemaObjects(ValidationContext vContext) Used during Query.validate() calls to collect the dbschema objects referenced in a query.
protected ThisType	getThisType()
boolean	hasParens() Returns true iff the output of this instance would include surrounding parentheses, false otherwise.
protected static boolean	hasParens(SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses) Determines if any of the given clauses are non-empty.
boolean	isDisableParens() Returns whether or not wrapping parentheses are disabled for this clause (for clauses which utilize wrapping parentheses).
boolean	isEmpty() Returns true iff the output of this instance would be an empty expression, false otherwise.
protected void	openParen(AppendableExt app) Appends an open parenthesis to the given AppendableExt if disableParens is true, otherwise does nothing.
ThisType	validate() Runs validation on this verifiable object.
void	validate(ValidationContext vContext) Runs validation on this verifiable object using a previously collected ValidationContext.

Methods inherited from class com.healthmarketscience.sqlbuilder.Expression

setDisableParens

Methods inherited from class com.healthmarketscience.sqlbuilder.SqlObject

collectSchemaObjects, doValidate, toString

Methods inherited from class com.healthmarketscience.common.util.AppendeeObject

toString, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

BaseCaseStatement

protected BaseCaseStatement(SqlObject operand)

Method Detail

isEmpty

public boolean isEmpty()

Returns true iff the output of this instance would be an empty expression, false otherwise.

Default implementation returns false.

addCustomWhen

public ThisType addCustomWhen(Object test,
                              Object result)

Adds a "WHEN" clause to the "CASE" statement.

All Object -> SqlObject conversions handled by Converter.toColumnSqlObject(Object).

Parameters:

test - the custom condition to test for this "WHEN" clause

result - the result to output if this "WHEN" clause is selected

addElse

public ThisType addElse(Object result)

Adds an "ELSE" clause to the "CASE" statement. Should be called at most once after all necessary calls to addWhen have been done.

Object -> SqlObject conversions handled by Converter.toColumnSqlObject(Object).

Parameters:

result - the result to output if no other "WHEN" clause is selected

addElseNull

public ThisType addElseNull()

Adds an "ELSE NULL" clause to the "CASE" statement. Should be called at most once after all necessary calls to addWhen have been done.

validate

public final ThisType validate()
                        throws ValidationException

Description copied from interface: Verifiable

Runs validation on this verifiable object.

Specified by:

validate in interface Verifiable<ThisType extends BaseCaseStatement<ThisType>>

Returns:

a handle to this instance

Throws:

ValidationException

validate

public void validate(ValidationContext vContext)
              throws ValidationException

Description copied from interface: Verifiable

Runs validation on this verifiable object using a previously collected ValidationContext.

In general, this method will only be called internally, not by users.

Specified by:

validate in interface Verifiable<ThisType extends BaseCaseStatement<ThisType>>

Parameters:

vContext - handle to the current, filled-in validation context

Throws:

ValidationException

collectSchemaObjects

protected void collectSchemaObjects(ValidationContext vContext)

Description copied from class: SqlObject

Used during Query.validate() calls to collect the dbschema objects referenced in a query. Any subclass of this class should add all referenced tables and columns to the appropriate collections.

Specified by:

collectSchemaObjects in class SqlObject

Parameters:

vContext - handle to the current validation context

appendTo

public void appendTo(AppendableExt app)
              throws IOException

Description copied from interface: Appendee

Appends this object to the given AppendableExt. Called by an AppendableExt when a request is made to append an instance of Appendee.

Specified by:

appendTo in interface Appendee

Overrides:

appendTo in class AppendeeObject

Parameters:

app - the AppendableExt to which this class should append itself

Throws:

IOException - if the append fails

getThisType

protected final ThisType getThisType()

Returns:

the handle to this object as the subclass type

isDisableParens

public boolean isDisableParens()

Returns whether or not wrapping parentheses are disabled for this clause (for clauses which utilize wrapping parentheses). Defaults to false.

hasParens

public boolean hasParens()

Returns true iff the output of this instance would include surrounding parentheses, false otherwise.

Default implementation returns !isEmpty() && !isDisableParens().

areEmpty

protected static boolean areEmpty(SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses)

Determines if any of the given clauses are non-empty.

Returns:

false if at least one clause is non-empty, true otherwise

hasParens

protected static boolean hasParens(SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses)

Determines if any of the given clauses are non-empty.

Returns:

false if at least one clause is non-empty, true otherwise

openParen

protected void openParen(AppendableExt app)
                  throws IOException

Appends an open parenthesis to the given AppendableExt if disableParens is true, otherwise does nothing.

Throws:

IOException

closeParen

protected void closeParen(AppendableExt app)
                   throws IOException

Appends a close parenthesis to the given AppendableExt if disableParens is true, otherwise does nothing.

Throws:

IOException

appendCustomIfNotNull

protected void appendCustomIfNotNull(AppendableExt app,
                                     SqlObject obj)
                              throws IOException

Appends the given custom clause to the given AppendableExt, handling null and enclosing parens.

Throws:

IOException

appendNestedClauses

protected void appendNestedClauses(AppendableExt app,
                                   SqlObjectList<? extends com.healthmarketscience.sqlbuilder.NestableClause> nestedClauses)
                            throws IOException

Appends the given nested clauses to the given AppendableExt, handling empty nested clauses and enclosing parens.

Throws:

IOException