Package org.gcube.informationsystem.resourceregistry.queries.operators

Enum Class MatemathicsOperator

java.lang.Object

java.lang.Enum<MatemathicsOperator>

org.gcube.informationsystem.resourceregistry.queries.operators.MatemathicsOperator

All Implemented Interfaces:

Serializable, Comparable<MatemathicsOperator>, Constable

public enum MatemathicsOperator
extends Enum<MatemathicsOperator>

Author:

Luca Frosini (ISTI - CNR) OrientDB supports the eval() function to execute complex operations. Example: SELECT eval( "amount * 120 / 100 - discount" ) as finalPrice from Order See https://www.orientdb.com/docs/3.0.x/sql/SQL-Where.html#mathematics-operators https://www.orientdb.com/docs/3.0.x/sql/SQL-Syntax.html#math-operators https://www.orientdb.com/docs/3.0.x/sql/SQL-Syntax.html#math-operators-precedence https://www.orientdb.com/docs/3.0.x/sql/SQL-Syntax.html#array-concatenation

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	MatemathicsOperator.FieldReference	Resolves the SQL operand of a field named among the values of a mathematics operator.

Nested classes/interfaces inherited from class java.lang.Enum

Enum.EnumDesc<E extends Enum<E>>

Enum Constant Summary

Enum Constants

Enum Constant	Description
ARRAY_CONCATENATION	The array concatenation operator (||).
BITWISE_AND	The bitwise AND operator (&).
BITWISE_LEFT_SHIFT	The bitwise left shift operator (<<).
BITWISE_OR	The bitwise OR operator (|).
BITWISE_RIGHT_SHIFT	The bitwise right shift operator (>>).
BITWISE_XOR	The bitwise XOR operator (^).
DIVIDE	The mathematical division operator (/).
MINUS	The mathematical subtraction operator (-).
MODULE	The mathematical modulo operator (%).
MULTIPLY	The mathematical multiplication operator (*).
SUM	The mathematical sum operator (+).

Field Summary

Fields

Modifier and Type	Field	Description
static final String	AS_KEY	The JSON property key for alias.
protected final String	dbOperator	The database operator symbol.
protected final String	description	The operator description.
protected static org.slf4j.Logger	logger	The logger instance.
protected final String	operatorKey	The internal operator key.
static final String	SEPARATOR_KEY	The JSON property key for separator.
static final String	VALUES_KEY	The JSON property key for values.

Method Summary

Modifier and Type	Method	Description
protected StringBuffer	addFieldPrefix(StringBuffer sb, String fieldPrefix)	Helper method to append the field name prefix to the SQL buffer.
String	generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.JsonNode jsonNode, String fieldPrefix)	Generates and returns the database SQL math expression representation of the JSON operator.
String	generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.JsonNode jsonNode, MatemathicsOperator.FieldReference fieldReference)	Generates and returns the database SQL math expression representation of the JSON operator.
protected StringBuffer	generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.node.ArrayNode arrayNode, String fieldsSeparator, MatemathicsOperator.FieldReference fieldReference)	Helper method to generate SQL math expressions for array elements.
protected String	getDbOperator()	Returns the database operator symbol.
String	getDescription()	Returns the operator description.
protected String	getError(String key, Class<?> clazz, boolean mandatory)	Throws a bad request exception indicating a query validation error.
static MatemathicsOperator	getOperator(String key)	Returns the matching MatemathicsOperator for the specified key.
protected String	getOperatorKey()	Returns the internal operator key.
static Set<String>	getOperators()	Returns the set of all recognized operator keys.
static MatemathicsOperator	valueOf(String name)	Returns the enum constant of this class with the specified name.
static MatemathicsOperator[]	values()	Returns an array containing the constants of this enum class, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

SUM

public static final MatemathicsOperator SUM

The mathematical sum operator (+).

MINUS

public static final MatemathicsOperator MINUS

The mathematical subtraction operator (-).

MULTIPLY

public static final MatemathicsOperator MULTIPLY

The mathematical multiplication operator (*).

DIVIDE

public static final MatemathicsOperator DIVIDE

The mathematical division operator (/).

MODULE

public static final MatemathicsOperator MODULE

The mathematical modulo operator (%).

BITWISE_RIGHT_SHIFT

public static final MatemathicsOperator BITWISE_RIGHT_SHIFT

The bitwise right shift operator (>>).

BITWISE_LEFT_SHIFT

public static final MatemathicsOperator BITWISE_LEFT_SHIFT

The bitwise left shift operator (<<).

BITWISE_AND

public static final MatemathicsOperator BITWISE_AND

The bitwise AND operator (&).

BITWISE_OR

public static final MatemathicsOperator BITWISE_OR

The bitwise OR operator (|).

BITWISE_XOR

public static final MatemathicsOperator BITWISE_XOR

The bitwise XOR operator (^).

ARRAY_CONCATENATION

public static final MatemathicsOperator ARRAY_CONCATENATION

The array concatenation operator (||).

Field Details

logger

protected static org.slf4j.Logger logger

The logger instance.

VALUES_KEY

public static final String VALUES_KEY

The JSON property key for values.

See Also:

• Constant Field Values

SEPARATOR_KEY

public static final String SEPARATOR_KEY

The JSON property key for separator.

See Also:

• Constant Field Values

AS_KEY

public static final String AS_KEY

The JSON property key for alias.

See Also:

• Constant Field Values

operatorKey

protected final String operatorKey

The internal operator key.

dbOperator

protected final String dbOperator

The database operator symbol.

description

protected final String description

The operator description.

Method Details

values

public static MatemathicsOperator[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:

an array containing the constants of this enum class, in the order they are declared

valueOf

public static MatemathicsOperator valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum class has no constant with the specified name

NullPointerException - if the argument is null

getOperatorKey

protected String getOperatorKey()

Returns the internal operator key.

Returns:

the operator key string

getDbOperator

protected String getDbOperator()

Returns the database operator symbol.

Returns:

the database operator symbol string

getDescription

public String getDescription()

Returns the operator description.

Returns:

the operator description string

getOperators

public static Set<String> getOperators()

Returns the set of all recognized operator keys.

Returns:

the set of operator keys

getOperator

public static MatemathicsOperator getOperator(String key)

Returns the matching MatemathicsOperator for the specified key.

Parameters:

key - the operator key

Returns:

the matching operator, or null if not found

getError

protected String getError(String key,
 Class<?> clazz,
 boolean mandatory)

Throws a bad request exception indicating a query validation error.

Parameters:

key - the field key

clazz - the expected class type

mandatory - true if the field is mandatory

Returns:

the error message string (unreachable as it always throws)

generateFieldToEmit

public String generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.JsonNode jsonNode,
 String fieldPrefix)
                           throws org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException

Generates and returns the database SQL math expression representation of the JSON operator.

Parameters:

jsonNode - the JSON node defining the operator and its values

fieldPrefix - the field name prefix to apply

Returns:

the generated SQL math expression string

Throws:

org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException - if a nested operator is not valid

generateFieldToEmit

public String generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.JsonNode jsonNode,
 MatemathicsOperator.FieldReference fieldReference)
                           throws org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException

Generates and returns the database SQL math expression representation of the JSON operator.

Parameters:

jsonNode - the JSON node defining the operator and its values

fieldReference - the resolver of the SQL operand of each named field

Returns:

the generated SQL math expression string

Throws:

org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException - if a field name or a nested operator is not valid

addFieldPrefix

protected StringBuffer addFieldPrefix(StringBuffer sb,
 String fieldPrefix)

Helper method to append the field name prefix to the SQL buffer.

Parameters:

sb - the SQL buffer

fieldPrefix - the prefix to apply

Returns:

the updated SQL buffer

generateFieldToEmit

protected StringBuffer generateFieldToEmit(org.gcube.com.fasterxml.jackson.databind.node.ArrayNode arrayNode,
 String fieldsSeparator,
 MatemathicsOperator.FieldReference fieldReference)
                                    throws org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException

Helper method to generate SQL math expressions for array elements.

Parameters:

arrayNode - the array of elements to process

fieldsSeparator - the separator to apply for string fields

fieldReference - the resolver of the SQL operand of each named field

Returns:

the updated SQL buffer

Throws:

org.gcube.informationsystem.resourceregistry.api.exceptions.queries.InvalidQueryException - if a field name or a nested operator is not valid