|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectdods.dap.DAS
public class DAS
The Data Attribute Structure is a set of name-value pairs used to describe the data in a particular dataset. The name-value pairs are called the "attributes." The values may be of any of the DODS simple data types (DByte, DInt32, DUInt32, DFloat64, DString and DURL), and may be scalar or vector. (Note that all values are actually stored as string data.)
A value may also consist of a set of other name-value pairs. This makes it possible to nest collections of attributes, giving rise to a hierarchy of attributes. DODS uses this structure to provide information about variables in a dataset.
In the following example of a DAS, several of the attribute
collections have names corresponding to the names of variables in
a hypothetical dataset. The attributes in that collection are said to
belong to that variable. For example, the lat
variable has an
attribute units
of degrees_north
.
Attributes may have arbitrary names, although in most datasets it is important to choose these names so a reader will know what they describe. In the above example, theAttributes { GLOBAL { String title "Reynolds Optimum Interpolation (OI) SST"; } lat { String units "degrees_north"; String long_name "Latitude"; Float64 actual_range 89.5, -89.5; } lon { String units "degrees_east"; String long_name "Longitude"; Float64 actual_range 0.5, 359.5; } time { String units "days since 1-1-1 00:00:00"; String long_name "Time"; Float64 actual_range 726468., 729289.; String delta_t "0000-00-07 00:00:00"; } sst { String long_name "Weekly Means of Sea Surface Temperature"; Float64 actual_range -1.8, 35.09; String units "degC"; Float64 add_offset 0.; Float64 scale_factor 0.0099999998; Int32 missing_value 32767; } }
GLOBAL
attribute provides
information about the entire dataset.
Data attribute information is an important part of the the data provided to a DODS client by a server, and the DAS is how this data is packaged for sending (and how it is received).
DDS
,
AttributeTable
,
Attribute
Constructor Summary | |
---|---|
DAS()
Create a new empty DAS . |
Method Summary | |
---|---|
void |
addAttributeTable(java.lang.String name,
AttributeTable a)
Adds an AttributeTable to the DAS. |
java.lang.Object |
clone()
Returns a clone of this DAS . |
AttributeTable |
getAttributeTable(java.lang.String name)
Returns the AttributeTable with the given name. |
java.util.Enumeration |
getNames()
Returns an Enumeration of the attribute names in this
DAS . |
void |
parse(java.io.InputStream is)
Reads a DAS from the named InputStream . |
void |
print(java.io.OutputStream os)
Print the DAS on the given OutputStream . |
void |
print(java.io.PrintWriter os)
Print the DAS on the given PrintWriter . |
Methods inherited from class java.lang.Object |
---|
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
---|
public DAS()
DAS
.
Method Detail |
---|
public java.lang.Object clone()
DAS
. A deep copy is performed on
all AttributeTable
s inside the DAS
.
clone
in class java.lang.Object
DAS
.public final java.util.Enumeration getNames()
Enumeration
of the attribute names in this
DAS
.
Use the getAttributeTable
method to get the
AttributeTable
for a given name.
Enumeration
of String
.getAttributeTable(String)
public final AttributeTable getAttributeTable(java.lang.String name)
AttributeTable
with the given name.
name
- the name of the AttributeTable
to return.
AttributeTable
with the specified name, or null
if there is no matching AttributeTable
.AttributeTable
public void addAttributeTable(java.lang.String name, AttributeTable a)
AttributeTable
to the DAS.
name
- the name of the AttributeTable
to add.a
- the AttributeTable
to add.AttributeTable
public void parse(java.io.InputStream is) throws ParseException, DASException
DAS
from the named InputStream
. This
method calls a generated parser to interpret an ASCII representation of a
DAS
, and regenerate that DAS
in memory.
is
- the InputStream
containing the DAS
to
parse.
ParseException
- error in parser.
DASException
- error in constructing DAS
.
TokenMgrError
- error in token manager
(unterminated quote).DASParser
public void print(java.io.PrintWriter os)
DAS
on the given PrintWriter
.
os
- the PrintWriter
to use for output.public final void print(java.io.OutputStream os)
DAS
on the given OutputStream
.
os
- the OutputStream
to use for output.print(PrintWriter)
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |