ucar.nc2

Class Structure

java.lang.Object

ucar.nc2.CDMNode

ucar.nc2.Variable

ucar.nc2.Structure

All Implemented Interfaces:

Comparable<VariableSimpleIF>, Iterable<Attribute>, AttributeContainer, ProxyReader, VariableSimpleIF

Direct Known Subclasses:

Sequence, StructureDS

public class Structure
extends Variable

A Structure is a type of Variable that contains other Variables, like a struct in C. A Structure can be scalar or multidimensional.

A call to structure.read() will read all of the data in a Structure, including nested structures, and returns an Array of StructureData, with all of the data in memory. If there is a nested sequence, the sequence data may be read into memory all at once, or it may be read in increments as the iteration proceeds.

Generally, the programmer can assume that the data in one Structure are stored together, so that it is efficient to read an entire Structure, and then access the Variable data through the Arrays in the StructureData.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Structure.Builder<T extends Structure.Builder<T>> A builder of Structures.

Field Summary

Fields inherited from class ucar.nc2.Variable

defaultCoordsSizeToCache, defaultSizeToCache, permitCaching

Method Summary

Modifier and Type	Method and Description
static Structure.Builder<?>	builder() Get Builder for this class that allows subclassing.
Variable	findVariable(String shortName) Find the Variable member with the specified (short) name.
int	getElementSize() Get the size of one element of the Structure.
String	getNameAndAttributes() Get String with name and attributes.
int	getNumberOfMemberVariables() Get the number of variables contained directly in this Structure.
StructureDataIterator	getStructureIterator() Iterator over all the data in a Structure.
StructureDataIterator	getStructureIterator(int bufferSize) Get an efficient iterator over all the data in the Structure.
com.google.common.collect.ImmutableList<String>	getVariableNames() Get the (short) names of the variables contained directly in this Structure.
com.google.common.collect.ImmutableList<Variable>	getVariables() Get the variables contained directly in this Structure.
boolean	isCaching() Caching is not allowed
boolean	isSubset() Find if this was created from a subset() method.
StructureMembers	makeStructureMembers() Create a StructureMembers object that describes this Structure.
StructureData	readStructure(int index) Use this when this is a one dimensional array of Structures, or you are doing the index calculation yourself for a multidimension array.
ArrayStructure	readStructure(int start, int count) For rank 1 array of Structures, read count Structures and return the data as an ArrayStructure.
Structure	select(List<String> memberNames) Create a subset of the Structure consisting only of the given member variables
Structure	select(String varName) Create a subset of the Structure consisting only of the one member variable
void	setCaching(boolean caching) Caching is not allowed
Structure.Builder<?>	toBuilder() Turn into a mutable Builder.

Methods inherited from class ucar.nc2.Variable

attributes, compareTo, createNewCache, equals, findAttribute, findAttributeString, findDimensionIndex, getDatasetLocation, getDataType, getDescription, getDimension, getDimensions, getDimensionsString, getEnumTypedef, getFileTypeId, getFullName, getNameAndDimensions, getNameAndDimensions, getNameAndDimensions, getNetcdfFile, getParentGroup, getParentStructure, getRanges, getRank, getShape, getShape, getShapeAsSection, getSize, getSizeToCache, getSPobject, getUnitsString, hasCachedData, hashCode, isCoordinateVariable, isMemberOfStructure, isMetadata, isScalar, isUnlimited, isVariableLength, lookupEnumString, read, read, read, read, read, readScalarByte, readScalarDouble, readScalarFloat, readScalarInt, readScalarLong, readScalarShort, readScalarString, readToStream, reallyRead, reallyRead, reduce, section, section, slice, toString, toStringDebug

Methods inherited from class ucar.nc2.CDMNode

getShortName

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface ucar.nc2.VariableSimpleIF

getShortName

Methods inherited from interface ucar.nc2.AttributeContainer

filter, findAttributeDouble, findAttributeIgnoreCase, findAttributeInteger, getName, hasAttribute, hasAttributeIgnoreCase, isEmpty, iterator

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

builder

public static Structure.Builder<?> builder()

Get Builder for this class that allows subclassing.

See Also:

"https://community.oracle.com/blogs/emcmanus/2010/10/24/using-builder-pattern-subclasses"

findVariable

public Variable findVariable(String shortName)

Find the Variable member with the specified (short) name.

Parameters:

shortName - name of the member variable.

Returns:

the Variable member with the specified (short) name, or null if not found.

getElementSize

public int getElementSize()

Get the size of one element of the Structure.

Overrides:

getElementSize in class Variable

Returns:

size (in bytes)

getNameAndAttributes

public String getNameAndAttributes()

Get String with name and attributes. Used in short descriptions like tooltips.

Returns:

name and attributes String

getNumberOfMemberVariables

public int getNumberOfMemberVariables()

Get the number of variables contained directly in this Structure.

getStructureIterator

public StructureDataIterator getStructureIterator()
                                           throws IOException

Iterator over all the data in a Structure.

 StructureDataIterator ii = structVariable.getStructureIterator();
 while (ii.hasNext()) {
   StructureData sdata = ii.next();
 }
 

Returns:

StructureDataIterator over type StructureData

Throws:

IOException - on read error

See Also:

getStructureIterator(int bufferSize)

getStructureIterator

public StructureDataIterator getStructureIterator(int bufferSize)
                                           throws IOException

Get an efficient iterator over all the data in the Structure. This is the efficient way to get all the data, it can be much faster than reading one record at a time, and is optimized for large datasets. This is accomplished by buffering bufferSize amount of data at once.

 Example:

  StructureDataIterator ii = structVariable.getStructureIterator(100 * 1000);
  while (ii.hasNext()) {
    StructureData sdata = ii.next();
  }
 

Parameters:

bufferSize - size in bytes to buffer, set < 0 to use default size

Returns:

StructureDataIterator over type StructureData

Throws:

IOException - on read error

getVariableNames

public com.google.common.collect.ImmutableList<String> getVariableNames()

Get the (short) names of the variables contained directly in this Structure.

getVariables

public com.google.common.collect.ImmutableList<Variable> getVariables()

Get the variables contained directly in this Structure.

isCaching

public boolean isCaching()

Caching is not allowed

Overrides:

isCaching in class Variable

Returns:

true is caching

isSubset

public boolean isSubset()

Find if this was created from a subset() method.

Returns:

true if this is a subset

makeStructureMembers

public StructureMembers makeStructureMembers()

Create a StructureMembers object that describes this Structure. CAUTION: Do not use for iterating over a StructureData or ArrayStructure - get the StructureMembers object directly from the StructureData or ArrayStructure.

Returns:

a StructureMembers object that describes this Structure.

readStructure

public StructureData readStructure(int index)
                            throws IOException,
                                   InvalidRangeException

Use this when this is a one dimensional array of Structures, or you are doing the index calculation yourself for a multidimension array. This will read only the ith structure, and return the data as a StructureData object.

Parameters:

index - index into 1D array

Returns:

ith StructureData

Throws:

IOException - on read error

InvalidRangeException - if index out of range

readStructure

public ArrayStructure readStructure(int start,
                                    int count)
                             throws IOException,
                                    InvalidRangeException

For rank 1 array of Structures, read count Structures and return the data as an ArrayStructure. Use only when this is a one dimensional array of Structures.

Parameters:

start - start at this index

count - return this many StructureData

Returns:

the StructureData recordsfrom start to start+count-1

Throws:

IOException - on read error

InvalidRangeException - if start, count out of range

select

public Structure select(List<String> memberNames)

Create a subset of the Structure consisting only of the given member variables

Parameters:

memberNames - list of Variable names, already a member

Returns:

Structure containing just those members

select

public Structure select(String varName)

Create a subset of the Structure consisting only of the one member variable

Parameters:

varName - name of member Variable

Returns:

containing just that member

setCaching

public void setCaching(boolean caching)

Caching is not allowed

Overrides:

setCaching in class Variable

Parameters:

caching - set if caching.

toBuilder

public Structure.Builder<?> toBuilder()

Turn into a mutable Builder. Can use toBuilder().build() to copy.

Overrides:

toBuilder in class Variable