Holds an 8-bit signed integer value. More...

#include <Int8.h>

Inheritance diagram for libdap::Int8:

Public Types
typedef stack< BaseType * >	btp_stack

Public Member Functions
virtual void	add_var (BaseType *bt, Part part=nil)
	Add a variable. More...

virtual void	add_var_nocopy (BaseType *bt, Part part=nil)

virtual bool	check_semantics (string &msg, bool all=false)
	Compare an object's current state with the semantics of its type. More...

virtual void	clear_local_data ()

virtual void	compute_checksum (Crc32 &checksum)
	include the data for this variable in the checksum DAP4 includes a checksum with every data response. This method adds the variable's data to that checksum. More...

virtual bool	d4_ops (BaseType *b, int op)

virtual string	dataset () const
	Returns the name of the dataset used to create this instance. More...

virtual void	deserialize (D4StreamUnMarshaller &um, DMR &dmr)

virtual void	dump (ostream &strm) const
	dumps information about this object More...

virtual int	element_count (bool leaves=false)
	Count the members of constructor types. More...

virtual std::string	FQN () const

virtual AttrTable &	get_attr_table ()

virtual BaseType *	get_parent () const

	Int8 (const string &n)

	Int8 (const string &n, const string &d)

	Int8 (const Int8 &copy_from)

virtual bool	is_constructor_type () const
	Returns true if the instance is a constructor (i.e., Structure, Sequence or Grid) type variable. More...

virtual bool	is_dap4 () const

virtual bool	is_in_selection ()
	Is this variable part of the current selection? More...

virtual bool	is_simple_type () const
	Returns true if the instance is a numeric, string or URL type variable. More...

virtual bool	is_vector_type () const
	Returns true if the instance is a vector (i.e., array) type variable. More...

virtual int	length () const
	How many elements are in this variable. More...

virtual string	name () const
	Returns the name of the class instance. More...

Int8 &	operator= (const Int8 &rhs)

virtual bool	ops (BaseType *b, int op)
	Evaluate relational operators. More...

virtual void	print_dap4 (XMLWriter &xml, bool constrained=false)

virtual void	print_decl (FILE *out, string space=" ", bool print_semi=true, bool constraint_info=false, bool constrained=false)
	Print an ASCII representation of the variable structure. More...

virtual void	print_decl (ostream &out, string space=" ", bool print_semi=true, bool constraint_info=false, bool constrained=false)
	Print an ASCII representation of the variable structure. More...

virtual void	print_val (ostream &out, string space="", bool print_decl_p=true)
	Prints the value of the variable. More...

virtual void	print_xml (FILE *out, string space=" ", bool constrained=false)

virtual void	print_xml (ostream &out, string space=" ", bool constrained=false)

virtual void	print_xml_writer (XMLWriter &xml, bool constrained=false)

virtual BaseType *	ptr_duplicate ()

virtual bool	read ()
	Read data into a local buffer. More...

virtual bool	read_p ()
	Has this variable been read? More...

virtual bool	send_p ()
	Should this variable be sent? More...

virtual void	serialize (D4StreamMarshaller &m, DMR &dmr, bool filter=false)
	Serialize an Int8. More...

virtual void	set_attr_table (const AttrTable &at)

virtual void	set_in_selection (bool state)

virtual void	set_is_dap4 (const bool v)

virtual void	set_length (int)
	Set the number of elements for this variable. More...

virtual void	set_name (const string &n)
	Sets the name of the class instance. More...

virtual void	set_parent (BaseType *parent)

virtual void	set_read_p (bool state)
	Sets the value of the read_p property. More...

virtual void	set_send_p (bool state)

virtual void	set_synthesized_p (bool state)

virtual void	set_type (const Type &t)
	Sets the type of the class instance. More...

virtual bool	set_value (dods_int8 val)

virtual bool	synthesized_p ()

virtual string	toString ()

virtual void	transfer_attributes (AttrTable *at)

virtual std::vector< BaseType * > *	transform_to_dap2 (AttrTable *parent_attr_table)
	DAP4 to DAP2 transform. More...

virtual void	transform_to_dap4 (D4Group root, Constructor container)
	DAP2 to DAP4 transform. More...

virtual Type	type () const
	Returns the type of the class instance. More...

virtual string	type_name () const
	Returns the type of the class instance as a string. More...

virtual dods_int8	value () const

virtual BaseType *	var (const string &name="", bool exact_match=true, btp_stack *s=0)
	Returns a pointer to a member of a constructor class. More...

virtual BaseType *	var (const string &name, btp_stack &s)

virtual unsigned int	width (bool constrained=false) const
	How many bytes does this variable use Return the number of bytes of storage this variable uses. For scalar types, this is pretty simple (an int32 uses 4 bytes, etc.). For arrays and Constructors, it is a bit more complex. Note that a scalar String variable uses sizeof(String) bytes, not the length of the string value. The width() of a String array returns the number of elements in the array times sizeof(String). More...


virtual D4Attributes *	attributes ()

virtual void	set_attributes (D4Attributes *)

virtual void	set_attributes_nocopy (D4Attributes *)

Abstract Methods
virtual void	intern_data (ConstraintEvaluator &eval, DDS &dds)

virtual void	intern_data ()
	Read data into this variable. More...

virtual bool	serialize (ConstraintEvaluator &eval, DDS &dds, Marshaller &m, bool ce_eval=true)
	Move data to the net, then remove them from the object. More...

virtual bool	deserialize (UnMarshaller &um, DDS *dds, bool reuse=false)
	Receive data from the net. More...

Protected Member Functions
void	m_duplicate (const BaseType &bt)
	Perform a deep copy. More...

Protected Attributes
dods_int8	d_buf

bool	d_in_selection

bool	d_is_synthesized

Detailed Description

Holds an 8-bit signed integer value.

Definition at line 42 of file Int8.h.

Constructor & Destructor Documentation

◆ Int8() [1/2]

libdap::Int8::Int8 ( const string & n )

The Int8 constructor accepts the name of the variable to be created.

Note: This type is available in DAP4 only. See http://docs.opendap.org/index.php/DAP4:_Specification_Volume_1#Atomic_Types

Parameters

n	A string containing the name of the variable to be created.

Definition at line 68 of file Int8.cc.

◆ Int8() [2/2]

libdap::Int8::Int8	(	const string &	n,
		const string &	d
	)

The Int8 server-side constructor accepts the name of the variable and the dataset name from which this instance is created. This is a signed 8-bit integer and was added for DAP4; Byte and UInt8 are unsigned 8-bit integers.

Note: This integer type cannot be used with DAP2; it is only present in DAP4. See http://docs.opendap.org/index.php/DAP4:_Specification_Volume_1#Atomic_Types.

Parameters

n	A string containing the name of the variable to be created.
d	A string containing the name of the dataset from which this variable is created

Definition at line 83 of file Int8.cc.

Member Function Documentation

◆ add_var()

void libdap::BaseType::add_var	(	BaseType *	bt,
		Part	part = `nil`
	)

virtualinherited

Add a variable.

Adds a variable to an instance of a constructor class, such as Array, Structure et cetera. This function is only used by those classes. For constructors with more than one variable, the variables appear in the same order in which they were added (i.e., the order in which add_var() was called). Since this method is only for use by Vectors and Constructors, the BaseType implementation throws InternalErr.

Note: For the implementation of this method in Structure, Sequence, et c., first copy bt and then insert the copy. If bt is itself a constructor type you must either use the var() method to get a pointer to the actual instance added to *this or you must first add all of bt's children to it before adding it to *this. The implementations should use m_duplicate() to perform a deep copy of bt.

Todo:: We should get rid of the Part parameter and adopt the convention that the first variable is the Array and all subsequent ones are Maps (when dealing with a Grid, the only time Part matters). This would enable several methods to migrate from Structure, Sequence and Grid to Constructor.

Parameters

bt	The variable to be added to this instance. The caller of this method must free memory it allocates for `v`. This method will make a deep copy of the object pointed to by `v`.
part	The part of the constructor data to be modified. Only meaningful for Grid variables.

See also: Part

Reimplemented in libdap::Vector, libdap::Array, libdap::Grid, and libdap::Constructor.

Definition at line 815 of file BaseType.cc.

◆ attributes()

D4Attributes * libdap::BaseType::attributes ( )

virtualinherited

DAP4 Attribute methods

Definition at line 599 of file BaseType.cc.

◆ check_semantics()

bool libdap::BaseType::check_semantics	(	string &	msg,
		bool	all = `false`
	)

virtualinherited

Compare an object's current state with the semantics of its type.

This function checks the class instance for internal consistency. This is important to check for complex constructor classes. For BaseType, an object is semantically correct if it has both a non-null name and type.

For example, an Int32 instance would return FALSE if it had no name or no type defined. A Grid instance might return FALSE for more complex reasons, such as having Map arrays of the wrong size or shape.

This function is used by the DDS class, and will rarely, if ever, be explicitly called by a DODS application program. A variable must pass this test before it is sent, but there may be many other stages in a retrieve operation where it would fail.

Returns: Returns FALSE when the current state violates some aspect of the type semantics, TRUE otherwise.

Parameters

msg	A returned string, containing a message indicating the source of any problem.
all	For complex constructor types (Grid, Sequence, Structure), this flag indicates whether to check the semantics of the member variables, too.

See also: DDS::check_semantics

Reimplemented in libdap::Array, libdap::Vector, libdap::Grid, and libdap::Constructor.

Definition at line 1209 of file BaseType.cc.

◆ clear_local_data()

virtual void libdap::BaseType::clear_local_data ( )

inlinevirtualinherited

Remove any read or set data in the private data of the variable, setting read_p() to false. Used to clear any dynamically allocated storage that holds (potentially large) data. For the simple types, this no-op version is all that's needed. Vector and some other classes define a special version and have serialize() implementations that call it to free data as soon as possible after sending it.

Note: Added 7/5/15 jhrg; Any specialization of this should make sure to reset the read_p property.

Reimplemented in libdap::Sequence, libdap::Vector, libdap::D4Sequence, and libdap::D4Opaque.

Definition at line 179 of file BaseType.h.

◆ compute_checksum()

void libdap::Int8::compute_checksum ( Crc32 & checksum )

virtual

include the data for this variable in the checksum DAP4 includes a checksum with every data response. This method adds the variable's data to that checksum.

Parameters

checksum A Crc32 instance that holds the current checksum.

Implements libdap::BaseType.

Definition at line 117 of file Int8.cc.

◆ d4_ops()

bool libdap::Int8::d4_ops	(	BaseType *	b,
		int	op
	)

virtual

See also: BaseType::d4_ops(BaseType *, int)

Reimplemented from libdap::BaseType.

Definition at line 187 of file Int8.cc.

◆ dataset()

string libdap::BaseType::dataset ( ) const

virtualinherited

Returns the name of the dataset used to create this instance.

A dataset from which the data is to be read. The meaning of this string will vary among different types of data sources. It may be the name of a data file or an identifier used to read data from a relational database.

Definition at line 358 of file BaseType.cc.

◆ deserialize() [1/2]

void libdap::Int8::deserialize	(	D4StreamUnMarshaller &	um,
		DMR &	dmr
	)

virtual

The DAP4 deserialization method.

Parameters

um
dmr

Exceptions

Error or InternalErr

Reimplemented from libdap::BaseType.

Definition at line 140 of file Int8.cc.

◆ deserialize() [2/2]

bool libdap::BaseType::deserialize	(	UnMarshaller &	um,
		DDS *	dds,
		bool	reuse = `false`
	)

virtualinherited

Receive data from the net.

Receives data from the network connection identified by the source parameter. The data is put into the class data buffer according to the input dds.

This function is only used on the client side of the DODS client/server connection.

Parameters

um	An UnMarshaller that knows how to deserialize data types
dds	The Data Descriptor Structure object corresponding to this dataset. See The DODS User Manual for information about this structure. This would have been received from the server in an earlier transmission.
reuse	A boolean value, indicating whether the class internal data storage can be reused or not. If this argument is TRUE, the class buffer is assumed to be large enough to hold the incoming data, and it is not reallocated. If FALSE, new storage is allocated. If the internal buffer has not been allocated at all, this argument has no effect.

Returns: Always returns TRUE.

Exceptions

Error when a problem reading from the UnMarshaller is found.

See also: DDS

Reimplemented in libdap::Sequence, libdap::D4Sequence, libdap::Vector, libdap::Constructor, libdap::Str, libdap::Int32, libdap::Byte, libdap::Float32, libdap::Float64, libdap::UInt32, libdap::Int16, libdap::UInt16, and libdap::D4Opaque.

Definition at line 943 of file BaseType.cc.

◆ dump()

void libdap::Int8::dump ( ostream & strm ) const

virtual

dumps information about this object

Displays the pointer value of this instance and information about this instance.

Parameters

strm	C++ i/o stream to dump the information to

Returns: void

Reimplemented from libdap::BaseType.

Definition at line 254 of file Int8.cc.

◆ element_count()

int libdap::BaseType::element_count ( bool leaves = false )

virtualinherited

Count the members of constructor types.

Return a count of the total number of variables in this variable. This is used to count the number of variables held by a constructor variable - for simple type and vector variables it always returns 1.

For compound data types, there are two ways to count members. You can count the members, or you can count the simple members and add that to the count of the compound members. For example, if a Structure contains an Int32 and another Structure that itself contains two Int32 members, the element count of the top-level structure could be two (one Int32 and one Structure) or three (one Int32 by itself and two Int32's in the subsidiary Structure). Use the leaves parameter to control which kind of counting you desire.

Returns: Returns 1 for simple types. For compound members, the count depends on the leaves argument.

Parameters

leaves This parameter is only relevant if the object contains other compound data types. If FALSE, the function counts only the data variables mentioned in the object's declaration. If TRUE, it counts the simple members, and adds that to the sum of the counts for the compound members. This parameter has no effect for simple type variables.

Reimplemented in libdap::Vector, and libdap::Constructor.

Definition at line 443 of file BaseType.cc.

◆ FQN()

string libdap::BaseType::FQN ( ) const

virtualinherited

Return the FQN for this variable. This will include the D4 Group component of the name.

Returns: The FQN in a string

Reimplemented in libdap::D4Group, and libdap::Constructor.

Definition at line 332 of file BaseType.cc.

◆ get_attr_table()

AttrTable & libdap::BaseType::get_attr_table ( )

virtualinherited

Get this variable's AttrTable. It's generally a bad idea to return a reference to a contained object, but in this case it seems that building an interface inside BaseType is overkill.

Use the AttrTable methods to manipulate the table.

Definition at line 582 of file BaseType.cc.

◆ get_parent()

BaseType * libdap::BaseType::get_parent ( ) const

virtualinherited

Return a pointer to the Constructor or Vector which holds (contains) this variable. If this variable is at the top level, this method returns null.

Returns: A BaseType pointer to the variable's parent.

Definition at line 751 of file BaseType.cc.

◆ intern_data() [1/2]

void libdap::BaseType::intern_data	(	ConstraintEvaluator &	eval,
		DDS &	dds
	)

virtualinherited

Similar to using serialize() and deserialize() together in one object. Data are read as for serialize and those values are stored in the objects as deserialize() does but does not write and then read data to/from a stream.

This method is defined by the various data type classes. It calls the read() abstract method. Unlike serialize(), this method does not clear the memory use to hold the data values, so the caller should make sure to delete the DDS or the variable as soon as possible.

Parameters

eval	Use this as the constraint expression evaluator.
dds	The Data Descriptor Structure object corresponding to this dataset. See The DODS User Manual for information about this structure.

Reimplemented in libdap::Sequence, libdap::D4Sequence, libdap::Vector, and libdap::Constructor.

Definition at line 908 of file BaseType.cc.

◆ intern_data() [2/2]

void libdap::BaseType::intern_data ( )

virtualinherited

Read data into this variable.

Parameters

eval	Evaluator for a constraint expression
dmr	DMR for the whole dataset

Reimplemented in libdap::D4Sequence, libdap::Vector, libdap::D4Group, and libdap::Constructor.

Definition at line 927 of file BaseType.cc.

◆ is_constructor_type()

bool libdap::BaseType::is_constructor_type ( ) const

virtualinherited

Returns true if the instance is a constructor (i.e., Structure, Sequence or Grid) type variable.

Returns: True if the instance is a Structure, Sequence or Grid, False otherwise.

Definition at line 412 of file BaseType.cc.

◆ is_in_selection()

bool libdap::BaseType::is_in_selection ( )

virtualinherited

Is this variable part of the current selection?

Does this variable appear in either the selection part or as a function argument in the current constrain expression. If this property is set (true) then implementations of the read() method should read this variable.

Note: This method does not check, nor does it know about the semantics of, string arguments passed to functions. Those functions might include variable names in strings; they are responsible for reading those variables. See the grid (func_grid_select()) for an example.

See also: BaseType::read()

Definition at line 703 of file BaseType.cc.

◆ is_simple_type()

bool libdap::BaseType::is_simple_type ( ) const

virtualinherited

Returns true if the instance is a numeric, string or URL type variable.

Returns: True if the instance is a scalar numeric, String or URL variable, False otherwise. Arrays (even of simple types) return False.

See also: is_vector_type()

Definition at line 393 of file BaseType.cc.

◆ is_vector_type()

bool libdap::BaseType::is_vector_type ( ) const

virtualinherited

Returns true if the instance is a vector (i.e., array) type variable.

Returns: True if the instance is an Array, False otherwise.

Definition at line 402 of file BaseType.cc.

◆ length()

virtual int libdap::BaseType::length ( ) const

inlinevirtualinherited

How many elements are in this variable.

Todo:: change the return type to int64_t

Returns: The number of elements; 1 for scalars

Reimplemented in libdap::Sequence, libdap::D4Sequence, libdap::Vector, libdap::Str, and libdap::D4Opaque.

Definition at line 207 of file BaseType.h.

◆ m_duplicate()

void libdap::BaseType::m_duplicate ( const BaseType & bt )

protectedinherited

Perform a deep copy.

Perform a deep copy. Copies the values of bt into *this. Pointers are dereferenced and their values are copied into a newly allocated instance.

Parameters

bt	The source object.

Definition at line 86 of file BaseType.cc.

◆ name()

string libdap::BaseType::name ( ) const

virtualinherited

Returns the name of the class instance.

Definition at line 320 of file BaseType.cc.

◆ ops()

bool libdap::Int8::ops	(	BaseType *	b,
		int	op
	)

virtual

Evaluate relational operators.

This method contains the relational operators used by the constraint expression evaluator in the DDS class. Each class that wants to be able to evaluate relational expressions must overload this function. The implementation in BaseType throws an InternalErr exception. The DAP library classes Byte, ..., Url provide specializations of this method. It is not meaningful for classes such as Array because relational expressions using Array are not supported.

The op argument refers to a table generated by bison from the constraint expression parser. Use statements like the following to correctly interpret its value:

switch (op) {
    case EQUAL: return i1 == i2;
    case NOT_EQUAL: return i1 != i2;
    case GREATER: return i1 > i2;
    case GREATER_EQL: return i1 >= i2;
    case LESS: return i1 < i2;
    case LESS_EQL: return i1 <= i2;
    case REGEXP: throw Error("Regular expressions are not supported for integer values");
    default: throw Error("Unknown operator");
}

This function is used by the constraint expression evaluator.

Parameters

b	Compare the value of this instance with b.
op	An integer index indicating which relational operator is implied. Choose one from the following: `EQUAL`, `NOT_EQUAL`, `GREATER`, `GREATER_EQL`, `LESS`, `LESS_EQL`, and `REGEXP`.

Returns: The boolean value of the comparison.

See also: BaseType::d4_ops(BaseType *, int)

Reimplemented from libdap::BaseType.

Definition at line 171 of file Int8.cc.

◆ print_dap4()

void libdap::BaseType::print_dap4	(	XMLWriter &	xml,
		bool	constrained = `false`
	)

virtualinherited

Write the DAP4 XML representation for this variable. This method is used to build the DAP4 DMR response object.

Parameters

xml	An XMLWriter that will do the serialization
constrained	True if the response should show the variables subject to the current constraint expression.

Reimplemented in libdap::Array, libdap::D4Group, and libdap::Constructor.

Definition at line 1164 of file BaseType.cc.

◆ print_decl() [1/2]

void libdap::BaseType::print_decl	(	FILE *	out,
		string	space = `" "`,
		bool	print_semi = `true`,
		bool	constraint_info = `false`,
		bool	constrained = `false`
	)

virtualinherited

Print an ASCII representation of the variable structure.

Write the variable's declaration in a C-style syntax. This function is used to create textual representation of the Data Descriptor Structure (DDS). See The DODS User Manual for information about this structure.

A simple array declaration might look like this:

Float64 lat[lat = 180];

While a more complex declaration (for a Grid, in this case), would look like this:

Grid {
ARRAY:
Int32 sst[time = 404][lat = 180][lon = 360];
MAPS:
Float64 time[time = 404];
Float64 lat[lat = 180];
Float64 lon[lon = 360];
} sst;

Parameters

out	The output stream on which to print the declaration.
space	Each line of the declaration will begin with the characters in this string. Usually used for leading spaces.
print_semi	A boolean value indicating whether to print a semicolon at the end of the declaration.
constraint_info	A boolean value indicating whether constraint information is to be printed with the declaration. If the value of this parameter is TRUE, `print_decl()` prints the value of the variable's `send_p()` flag after the declaration.
constrained	If this boolean value is TRUE, the variable's declaration is only printed if is the `send_p()` flag is TRUE. If a constraint expression is in place, and this variable is not requested, the `send_p()` flag is FALSE.

See also: DDS; DDS::CE

Reimplemented in libdap::Array, libdap::Grid, and libdap::Constructor.

Definition at line 1003 of file BaseType.cc.

◆ print_decl() [2/2]

void libdap::BaseType::print_decl	(	ostream &	out,
		string	space = `" "`,
		bool	print_semi = `true`,
		bool	constraint_info = `false`,
		bool	constrained = `false`
	)

virtualinherited

Print an ASCII representation of the variable structure.

Write the variable's declaration in a C-style syntax. This function is used to create textual representation of the Data Descriptor Structure (DDS). See The DODS User Manual for information about this structure.

A simple array declaration might look like this:

Float64 lat[lat = 180];

While a more complex declaration (for a Grid, in this case), would look like this:

Grid {
ARRAY:
Int32 sst[time = 404][lat = 180][lon = 360];
MAPS:
Float64 time[time = 404];
Float64 lat[lat = 180];
Float64 lon[lon = 360];
} sst;

Parameters

out	The output stream on which to print the declaration.
space	Each line of the declaration will begin with the characters in this string. Usually used for leading spaces.
print_semi	A boolean value indicating whether to print a semicolon at the end of the declaration.
constraint_info	A boolean value indicating whether constraint information is to be printed with the declaration. If the value of this parameter is TRUE, `print_decl()` prints the value of the variable's `send_p()` flag after the declaration.
constrained	If this boolean value is TRUE, the variable's declaration is only printed if is the `send_p()` flag is TRUE. If a constraint expression is in place, and this variable is not requested, the `send_p()` flag is FALSE.

See also: DDS; DDS::CE

Reimplemented in libdap::Array, libdap::Grid, and libdap::Constructor.

Definition at line 1054 of file BaseType.cc.

◆ print_val()

void libdap::Int8::print_val	(	ostream &	out,
		string	space = `""`,
		bool	print_decl_p = `true`
	)

virtual

Prints the value of the variable.

Prints the value of the variable, with its declaration. This function is primarily intended for debugging DODS applications. However, it can be overloaded and used to do some useful things. Take a look at the asciival and writeval clients, both of which overload this to output the values of variables in different ways.

Parameters

out	The output ostream on which to print the value.
space	This value is passed to the print_decl() function, and controls the leading spaces of the output.
print_decl_p	A boolean value controlling whether the variable declaration is printed as well as the value.

Implements libdap::BaseType.

Definition at line 160 of file Int8.cc.

◆ print_xml() [1/2]

void libdap::BaseType::print_xml	(	FILE *	out,
		string	space = `" "`,
		bool	constrained = `false`
	)

virtualinherited

Write the XML representation of this variable. This method is used to build the DDX XML response.

Parameters

out	Destination.
space	Use this to indent child declarations. Default is "".
constrained	If true, only print this if it's part part of the current projection. Default is False.

Deprecated:

Reimplemented in libdap::Array, libdap::Grid, and libdap::Constructor.

Definition at line 1105 of file BaseType.cc.

◆ print_xml() [2/2]

void libdap::BaseType::print_xml	(	ostream &	out,
		string	space = `" "`,
		bool	constrained = `false`
	)

virtualinherited

Write the XML representation of this variable. This method is used to build the DDX XML response.

Parameters

out	Destination output stream
space	Use this to indent child declarations. Default is "".
constrained	If true, only print this if it's part part of the current projection. Default is False.

Deprecated:

Reimplemented in libdap::Array, libdap::Grid, and libdap::Constructor.

Definition at line 1120 of file BaseType.cc.

◆ print_xml_writer()

void libdap::BaseType::print_xml_writer	(	XMLWriter &	xml,
		bool	constrained = `false`
	)

virtualinherited

Write the XML representation of this variable. This method is used to build the DDX XML response.

Parameters

out	Destination output stream
space	Use this to indent child declarations. Default is "".
constrained	If true, only print this if it's part part of the current projection. Default is False.

Reimplemented in libdap::Array, libdap::D4Enum, libdap::Grid, and libdap::Constructor.

Definition at line 1134 of file BaseType.cc.

◆ ptr_duplicate()

BaseType * libdap::Int8::ptr_duplicate ( )

virtual

Clone this instance. Allocate a new instance and copy *this into it. This method must perform a deep copy.

@note This method should \e not copy data values, but must copy all
other fields in the object.

Returns: A newly allocated copy of this.

Implements libdap::BaseType.

Definition at line 92 of file Int8.cc.

◆ read()

bool libdap::BaseType::read ( )

virtualinherited

Read data into a local buffer.

This method should be implemented for each of the data type classes (Byte, ..., Grid) when using the DAP class library to build a server. This method is only for DAP servers. The library provides a default definition here which throws an InternalErr exception unless the read_p property has been set. In that case it returns false, indicating that all the data have been read. The latter case can happen when building a constant value that needs to be passed to a function. The variable/constant is loaded with a value when it is created.

When implementing a new DAP server, the Byte, ..., Grid data type classes are usually specialized. In each of those specializations read() should be defined to read values from the data source and store them in the object's local buffer. The read() method is called by other methods in this library. When writing read(), follow these rules:

read() should throw Error if it encounters an error. The message should be verbose enough to be understood by someone running a client on a different machine.
The value(s) should be read if and only if either send_p() or is_in_selection() return true. If neither of these return true, the value(s) should not be read. This is important when writing read() for a Constructor type such as Grid where a client may ask for only the map vectors (and thus reading the much larger Array part is not needed).
For each specialization of read(), the method should first test the value of the read_p property (using the read_p() method) and read values only if the value of read_p() is false. Once the read() method reads data and stores it in the instance, it must set the value of the read_p property to true using set_read_p(). If your read() methods fail to do this data may not serialize correctly.
The Array::read() and Grid::read() methods should take into account any restrictions on Array sizes.
If you are writing Sequence::read(), be sure to check the documentation for Sequence::read_row() and Sequence::serialize() so you understand how Sequence::read() is being called.
For Sequence::read(), your specialization must correctly manage the unsent_data property and row count in addition to the read_p property (handle the read_p property as describe above). For a Sequence to serialize correctly, once all data from the Sequence has been read, unsent_data property must be set to false (use Sequence::set_unsent_data()). Also, at that time the row number counter must be reset (use Sequence::reset_row_counter()). Typically the correct time to set unsent_data to false and reset the row counter is the time when Sequence::read() return false indicating that all the data for the Sequence have been read. Failure to handle these tasks will break serialization of nested Sequences. Note that when Sequence::read() returns with a result of true (indicating there is more data to send, the value of the unsent_data property should be true.

Also, if you server must handle nested sequences, be sure to read about subclassing set_read_p().

Todo:: Modify the D4 serialize code so that it supports the true/false behavior of read() for arrays.

Todo:: Modify all of the stock handlers so they conform to this!

Returns: False means more data remains to be read, True indicates that no more data need to be read. For Sequence and D4Sequence, this method will generally read one instance of the Sequence; for other types it will generally read the entire variable modulo any limitations due to a constraint. However, the library should be written so that read can return less than all of the data for a variable - serialize() would then call the function until it returns True.

See also: BaseType

Reimplemented in libdap::Constructor.

Definition at line 899 of file BaseType.cc.

◆ read_p()

bool libdap::BaseType::read_p ( )

virtualinherited

Has this variable been read?

Returns true if the value(s) for this variable have been read from the data source, otherwise returns false. This method is used to determine when values need to be read using the read() method. When read_p() returns true, this library assumes that buf2val() (and other methods such as get_vec()) can be used to access the value(s) of a variable.

Returns: True if the variable's value(s) have been read, false otherwise.

Definition at line 480 of file BaseType.cc.

◆ send_p()

bool libdap::BaseType::send_p ( )

virtualinherited

Should this variable be sent?

Returns the state of the send_p property. If true, this variable should be sent to the client, if false, it should not. If no constraint expression (CE) has been evaluated, this property is true for all variables in a data source (i.e., for all the variables listed in a DDS). If a CE has been evaluated, this property is true only for those variables listed in the projection part of the CE.

Returns: True if the variable should be sent to the client, false otherwise.

Definition at line 554 of file BaseType.cc.

◆ serialize() [1/2]

void libdap::Int8::serialize	(	D4StreamMarshaller &	m,
		DMR &	dmr,
		bool	filter = `false`
	)

virtual

Serialize an Int8.

Parameters

m
dmr	Unused
eval	Unused
filter	Unused

Exceptions

Error is thrown if the value needs to be read and that operation fails.

Reimplemented from libdap::BaseType.

Definition at line 131 of file Int8.cc.

◆ serialize() [2/2]

bool libdap::BaseType::serialize	(	ConstraintEvaluator &	eval,
		DDS &	dds,
		Marshaller &	m,
		bool	ce_eval = `true`
	)

virtualinherited

Move data to the net, then remove them from the object.

Sends the data from the indicated (local) dataset through the connection identified by the Marshaller parameter. If the data is not already incorporated into the DDS object, read the data from the dataset. Once the data are sent (written to the Marshaller), they are deleted from the object and the object state is reset so that they will be read again if the read() method is called.

This function is only used on the server side of the client/server connection, and is generally only called from the ResponseBuilder functions. It has no BaseType implementation; each datatype child class supplies its own implementation.

@param eval Use this as the constraint expression evaluator.

Parameters

dds	The Data Descriptor Structure object corresponding to this dataset. See The DODS User Manual for information about this structure.
m	A marshaller used to serialize data types
ce_eval	A boolean value indicating whether to evaluate the DODS constraint expression that may accompany this dataset. The constraint expression is stored in the dds.

Returns: This method always returns true. Older versions used the return value to signal success or failure.

Note: We changed the default behavior of this method so that it calls BaseType::clear_local_data() once the values are sent. This, combined with the behavior that read() is called by this method just before data are sent, means that data for any given variable remain in memory for the shortest time possible. Furthermore, since variables are serialized one at a time, no more than one variable's data will be in memory at any given time when using the default behavior. Some code - code that uses intern_data() or server functions - might alter this default behavior. Only Array (i.e. Vector), Sequence, D4Sequence and D4Opaque types actually hold data in dynamically allocated memory, so sonly those types have the new/changed behavior. This change was made on 7/5/15.

Exceptions

InternalErr.
Error.

See also: DDS

Reimplemented in libdap::Sequence, libdap::D4Sequence, libdap::Vector, libdap::Constructor, libdap::Str, libdap::Int32, libdap::Byte, libdap::Float32, libdap::Float64, libdap::UInt32, libdap::Int16, libdap::UInt16, and libdap::D4Opaque.

Definition at line 937 of file BaseType.cc.

◆ set_attr_table()

void libdap::BaseType::set_attr_table ( const AttrTable & at )

virtualinherited

Set this variable's attribute table.

Parameters

at	Source of the attributes.

Definition at line 590 of file BaseType.cc.

◆ set_in_selection()

void libdap::BaseType::set_in_selection ( bool state )

virtualinherited

Set the in_selection property to state. This property indicates that the variable is used as a parameter to a constraint expression function or that it appears as an argument in a selection sub-expression. If set (true), implementations of the BaseType::read() method should read this variable.

Parameters

state Set the in_selection property to this state.

See also: BaseType::read(); BaseType::is_in_selection() for more information.

Reimplemented in libdap::Constructor.

Definition at line 718 of file BaseType.cc.

◆ set_length()

virtual void libdap::BaseType::set_length ( int )

inlinevirtualinherited

Set the number of elements for this variable.

Todo:: change param type to int64_t

Parameters

l	The number of elements

Reimplemented in libdap::D4Sequence, and libdap::Vector.

Definition at line 214 of file BaseType.h.

◆ set_name()

void libdap::BaseType::set_name ( const string & n )

virtualinherited

Sets the name of the class instance.

Reimplemented in libdap::Vector.

Definition at line 344 of file BaseType.cc.

◆ set_parent()

void libdap::BaseType::set_parent ( BaseType * parent )

virtualinherited

Set the parent property for this variable.

Note: Added ability to set parent to null. 10/19/12 jhrg

Parameters

parent Pointer to the Constructor of Vector parent variable or null if the variable has no parent (if it is at the top-level of a DAP2/3 DDS).

Exceptions

InternalErr thrown if called with anything other than a Constructor, Vector or Null.

Definition at line 733 of file BaseType.cc.

◆ set_read_p()

void libdap::BaseType::set_read_p ( bool state )

virtualinherited

Sets the value of the read_p property.

Sets the value of the read_p property. This indicates that the value(s) of this variable has/have been read. An implementation of the read() method should use this to set the read_p property to true.

Note: If the is_synthesized property is true, this method will not alter the is_read property. If you need that behavior, specialize the method in your subclasses if the various types.; For most of the types the default implementation of this method is fine. However, if you're building a server which must handle data represented using nested sequences, then you may need to provide a specialization of Sequence::set_read_p(). By default Sequence::set_read_p() recursively sets the read_p property for all child variables to state. For servers where one Sequence reads an outer set of values and another reads an inner set, this is cumbersome. In such a case, it is easier to specialize Sequence::set_read_p() so that it does not recursively set the read_p property for the inner Sequence. Be sure to see the documentation for the read() method!

Todo:: Look at making synthesized variables easier to implement and at making them more integrated into the overall CE evaluation process. Maybe the code that computes the synthesized var's value should be in the that variable's read() method? This might provide a way to get rid of the awkward 'projection functions' by replacing them with real children of BaseType. It would also provide a way to clean up the way the synthesized_p prop intrudes on the read_p prop.

See also: BaseType::read()

Parameters

state Set the read_p property to this state.

Reimplemented in libdap::Vector, libdap::D4Group, and libdap::Constructor.

Definition at line 516 of file BaseType.cc.

◆ set_send_p()

void libdap::BaseType::set_send_p ( bool state )

virtualinherited

Sets the value of the send_p flag. This function is meant to be called from within the constraint evaluator of other code which determines that this variable should be returned to the client. Data are ready to be sent when both the d_is_send and d_is_read flags are set to TRUE.

Parameters

state The logical state to set the send_p flag.

Reimplemented in libdap::Vector, libdap::D4Group, and libdap::Constructor.

Definition at line 568 of file BaseType.cc.

◆ set_synthesized_p()

void libdap::BaseType::set_synthesized_p ( bool state )

virtualinherited

Set the synthesized flag. Before setting this flag be sure to set the read_p() state. Once this flag is set you cannot alter the state of the read_p flag!

See also: synthesized_p()

Definition at line 463 of file BaseType.cc.

◆ set_type()

void libdap::BaseType::set_type ( const Type & t )

virtualinherited

Sets the type of the class instance.

Definition at line 372 of file BaseType.cc.

◆ synthesized_p()

bool libdap::BaseType::synthesized_p ( )

virtualinherited

Returns true if the variable is a synthesized variable. A synthesized variable is one that is added to the dataset by the server (usually with a `projection function'.

Definition at line 452 of file BaseType.cc.

◆ toString()

string libdap::BaseType::toString ( )

virtualinherited

Write out the object's internal fields in a string. To be used for debugging when regular inspection w/ddd or gdb isn't enough.

Returns: A string which shows the object's internal stuff.

Reimplemented in libdap::Sequence.

Definition at line 184 of file BaseType.cc.

◆ transfer_attributes()

void libdap::BaseType::transfer_attributes ( AttrTable * at_container )

virtualinherited

Transfer attributes from a DAS object into this variable. Because of the rough history of the DAS object and the way that various server code built the DAS, this is necessarily a heuristic process. The intent is that this method will be overridden by handlers that need to look for certain patterns in the DAS (e.g., hdf4's odd variable_dim_n; where n = 0, 1, 2, ...) attribute containers.

There should be a one-to-one mapping between variables and attribute containers. However, in some cases one variable has attributes spread across several top level containers and in some cases one container is used by several variables

Note: This method is technically unnecessary because a server (or client) can easily add attributes directly using the DDS::get_attr_table or BaseType::get_attr_table methods and then poke values in using any of the methods AttrTable provides. This method exists to ease the transition to DDS objects which contain attribute information for the existing servers (Since they all make DAS objects separately from the DDS). They could be modified to use the same AttrTable methods but operate on the AttrTable instances in a DDS/BaseType instead of those in a DAS.

Parameters

at_container Transfer attributes from this container.

Returns: void

Reimplemented in libdap::Grid, and libdap::Constructor.

Definition at line 644 of file BaseType.cc.

◆ transform_to_dap2()

std::vector< BaseType * > * libdap::Int8::transform_to_dap2 ( AttrTable * parent_attr_table )

virtual

DAP4 to DAP2 transform.

Return a DAP2 'copy' of the variable. In this case, since Int8 doesn't have a natural representation in DAP2 we are going to just call it a Byte . Why? Because SIZE.

Parameters

root	The root group that should hold this new variable. Add Group-level stuff here (e.g., D4Dimensions).
container	Add the new variable to this container.

Returns: A pointer to the transformed variable

Reimplemented from libdap::BaseType.

Definition at line 232 of file Int8.cc.

◆ transform_to_dap4()

void libdap::BaseType::transform_to_dap4	(	D4Group *	root,
		Constructor *	container
	)

virtualinherited

DAP2 to DAP4 transform.

For the current BaseType, return a DAP4 'copy' of the variable.

Note: For most DAP2 types, in this implementation of DAP4 the corresponding DAP4 type is the same. The different types are Sequences (which are D4Sequences in the DAP4 implementation), Grids (which are coverages) and Arrays (which use shared dimensions).

Parameters

root	The root group that should hold this new variable. Add Group-level stuff here (e.g., D4Dimensions).
container	Add the new variable to this container.

Returns: A pointer to the transformed variable

Reimplemented in libdap::Sequence, libdap::Array, libdap::Grid, libdap::Structure, and libdap::Constructor.

Definition at line 216 of file BaseType.cc.

◆ type()

Type libdap::BaseType::type ( ) const

virtualinherited

Returns the type of the class instance.

Definition at line 365 of file BaseType.cc.

◆ type_name()

string libdap::BaseType::type_name ( ) const

virtualinherited

Returns the type of the class instance as a string.

Definition at line 379 of file BaseType.cc.

◆ var() [1/2]

BaseType * libdap::BaseType::var	(	const string &	name = `""`,
		bool	exact_match = `true`,
		btp_stack *	s = `0`
	)

virtualinherited

Returns a pointer to a member of a constructor class.

Returns a pointer to the contained variable in a composite class. The composite classes are those made up of aggregated simple data types. Array, Grid, and Structure are composite types, while Int and Float are simple types. This function is only used by composite classes. The BaseType implementation always returns null.

Several of the subclasses provide alternate access methods that make sense for that particular data type. For example, the Array class defines a *var(int i) method that returns the ith entry in the Array data, and the Structure provides a *var(Vars_iter) function using a pseudo-index to access the different members of the structure.

Parameters

name	The name of the class member. Defaults to ""
exact_match	True if only interested in variables whose full names match n exactly. If false, returns the first variable whose name matches name. For example, if name is `x` and `point.x` is a variable, then var("x", false) would return a BaseType pointer to `point.x`. If exact_match was `true` then name would need to be `"point.x"` for var to return that pointer. This feature simplifies constraint expressions for datasets which have complex, nested, constructor variables. Defaults to true.
s	Record the path to name. Defaults to null, in which case it is not used.

Returns: A pointer to the member named in the n argument. If no name is given, the function returns the first (only) variable. For example, an Array has only one variable, while a Structure can have many.

Reimplemented in libdap::Vector, and libdap::Constructor.

Definition at line 758 of file BaseType.cc.

◆ var() [2/2]

BaseType * libdap::BaseType::var	(	const string &	name,
		btp_stack &	s
	)

virtualinherited

This version of var(...) searches for name and returns a pointer to the BaseType object if found. It uses the same search algorithm as BaseType::var(const string &, bool, btp_stack *) when exact_match is false. In addition to returning a pointer to the variable, it pushes onto s a BaseType pointer to each constructor type that ultimately contains name.

Note: The BaseType implementation always returns null. There are no default values for the parameters. If var() is called w/o any params, the three parameter version will be used.

Deprecated:: This method is deprecated because it tries first to use exact_match and, if that fails, then tries leaf_match. It's better to use the alternate form of var(...) and specify exactly what you'd like to do.

Returns: A pointer to the named variable.

Reimplemented in libdap::Vector, and libdap::Constructor.

Definition at line 780 of file BaseType.cc.

◆ width()

unsigned int libdap::Int8::width ( bool constrained = false ) const

virtual

How many bytes does this variable use Return the number of bytes of storage this variable uses. For scalar types, this is pretty simple (an int32 uses 4 bytes, etc.). For arrays and Constructors, it is a bit more complex. Note that a scalar String variable uses sizeof(String*) bytes, not the length of the string value. The width() of a String array returns the number of elements in the array times sizeof(String*).

Parameters

constrained Should the current constraint be taken into account?

Returns: Bytes of storage

Reimplemented from libdap::BaseType.

Definition at line 111 of file Int8.cc.

The documentation for this class was generated from the following files:

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Int8() [1/2]

◆ Int8() [2/2]

Member Function Documentation

◆ add_var()

◆ attributes()

◆ check_semantics()

◆ clear_local_data()

◆ compute_checksum()

◆ d4_ops()

◆ dataset()

◆ deserialize() [1/2]

◆ deserialize() [2/2]

◆ dump()

◆ element_count()

◆ FQN()

◆ get_attr_table()

◆ get_parent()

◆ intern_data() [1/2]

◆ intern_data() [2/2]

◆ is_constructor_type()

◆ is_in_selection()

◆ is_simple_type()

◆ is_vector_type()

◆ length()

◆ m_duplicate()

◆ name()

◆ ops()

◆ print_dap4()

◆ print_decl() [1/2]

◆ print_decl() [2/2]

◆ print_val()

◆ print_xml() [1/2]

◆ print_xml() [2/2]

◆ print_xml_writer()

◆ ptr_duplicate()

◆ read()

◆ read_p()

◆ send_p()

◆ serialize() [1/2]

◆ serialize() [2/2]

◆ set_attr_table()

◆ set_in_selection()

◆ set_length()

◆ set_name()

◆ set_parent()

◆ set_read_p()

◆ set_send_p()

◆ set_synthesized_p()

◆ set_type()

◆ synthesized_p()

◆ toString()

◆ transfer_attributes()

◆ transform_to_dap2()

◆ transform_to_dap4()

◆ type()

◆ type_name()

◆ var() [1/2]

◆ var() [2/2]

◆ width()