ucar.nc2.iosp

Class AbstractIOServiceProvider

java.lang.Object

ucar.nc2.iosp.AbstractIOServiceProvider

All Implemented Interfaces:

Closeable, AutoCloseable, IOServiceProvider

Direct Known Subclasses:

H4iosp, H5iosp, N3iosp, NcStreamIosp

public abstract class AbstractIOServiceProvider
extends Object
implements IOServiceProvider

Abstract base class for IOSP implementations that provides default implementations of readToByteChannel(...) and readSection(...).

Implementations should make sure to handle the RandomAccessFile properly by doing one of the following:

1. Write your own open(...) and close() methods that keep track of the RandomAccessFile, be sure to close the RandomAccessFile in your close() method.
2. Write your own open(...) and close() methods that call the open(...) and close() methods defined here, use the "raf" variable also defined here.
3. Don't write an open(...) or close() method, so that those defined here are used.

Field Summary

Fields

Modifier and Type	Field and Description
protected String	location
protected NetcdfFile	ncfile
protected RandomAccessFile	raf Subclasses that use AbstractIOServiceProvider.open(...) or close() should use this (instead of their own private variable).
protected int	rafOrder

Constructor Summary

Constructors

Constructor and Description
AbstractIOServiceProvider()

Method Summary

Modifier and Type	Method and Description
void	buildFinish(NetcdfFile ncfile) Sometimes the builder needs access to the finished objects.
void	close() Close the file.
String	getDetailInfo() Show debug / underlying implementation details
String	getFileTypeVersion() Get the version of this file type.
long	getLastModified() Returns the time that the underlying file(s) were last modified.
Iterator<StructureData>	getStructureDataArrayIterator(Sequence s, int bufferSize) Get the structure iterator.
StructureDataIterator	getStructureIterator(Structure s, int bufferSize) Deprecated. do not use.
void	open(RandomAccessFile raf, NetcdfFile ncfile, CancelTask cancelTask)
void	reacquire() Reacquire any resources like file handles Used when reactivating in cache.
Array<?>	readArrayData(Variable v2, Section section) Read data from a top level Variable and return a memory resident Array.
Array	readSection(ParsedSectionSpec cer) Deprecated. do not use.
long	readToOutputStream(Variable v2, Section section, OutputStream out) Deprecated. do not use.
void	release() Release any system resources like file handles.
Object	sendIospMessage(Object message) A way to communicate arbitrary information to and from an iosp.
void	setNetcdfFile(NetcdfFile ncfile)
String	toStringDebug(Object o) Debug info for this object.

Methods inherited from class java.lang.Object

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

Methods inherited from interface ucar.nc2.iosp.IOServiceProvider

build, getFileTypeDescription, getFileTypeId, isValidFile, readData

Field Detail

raf

protected RandomAccessFile raf

Subclasses that use AbstractIOServiceProvider.open(...) or close() should use this (instead of their own private variable).

location

protected String location

rafOrder

protected int rafOrder

ncfile

protected NetcdfFile ncfile

Constructor Detail

AbstractIOServiceProvider

public AbstractIOServiceProvider()

Method Detail

open

public void open(RandomAccessFile raf,
                 NetcdfFile ncfile,
                 CancelTask cancelTask)
          throws IOException

Throws:

IOException

setNetcdfFile

public void setNetcdfFile(NetcdfFile ncfile)

buildFinish

public void buildFinish(NetcdfFile ncfile)

Description copied from interface: IOServiceProvider

Sometimes the builder needs access to the finished objects. This is called when ncfile is finished being built.

Specified by:

buildFinish in interface IOServiceProvider

close

public void close()
           throws IOException

Description copied from interface: IOServiceProvider

Close the file. It is the IOServiceProvider's job to close the file (even though it didnt open it), and to free any other resources it has used.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in interface IOServiceProvider

Throws:

IOException - if read error

release

public void release()
             throws IOException

Description copied from interface: IOServiceProvider

Release any system resources like file handles. Optional, implement only if you are able to reacquire. Used when object is made inactive in cache.

Specified by:

release in interface IOServiceProvider

Throws:

IOException

reacquire

public void reacquire()
               throws IOException

Description copied from interface: IOServiceProvider

Reacquire any resources like file handles Used when reactivating in cache.

Specified by:

reacquire in interface IOServiceProvider

Throws:

IOException

readArrayData

public Array<?> readArrayData(Variable v2,
                              Section section)
                       throws IOException,
                              InvalidRangeException

Description copied from interface: IOServiceProvider

Read data from a top level Variable and return a memory resident Array. This Array has the same element type as the Variable, and the requested shape.

Specified by:

readArrayData in interface IOServiceProvider

Parameters:

v2 - a top-level Variable

section - the section of data to read. There must be a Range for each Dimension in the variable, in order. Note: no nulls allowed. IOSP may not modify.

Returns:

the requested data in a memory-resident Array

Throws:

IOException

InvalidRangeException

readToOutputStream

@Deprecated
public long readToOutputStream(Variable v2,
                                            Section section,
                                            OutputStream out)
                                     throws IOException,
                                            InvalidRangeException

Deprecated. do not use.

Description copied from interface: IOServiceProvider

Read data from a top level Variable and send data to a OutputStream. Must be in big-endian order, following ncstream conventions. Default implementation just reads to memory and writes to stream. Allow override for possible performance improvements.

Specified by:

readToOutputStream in interface IOServiceProvider

Parameters:

v2 - a top-level Variable

section - the section of data to read. There must be a Range for each Dimension in the variable, in order. Note: no nulls allowed. IOSP may not modify.

out - write data to this OutputStream

Returns:

the number of bytes written to the channel

Throws:

IOException - if read error

InvalidRangeException - if invalid section

readSection

@Deprecated
public Array readSection(ParsedSectionSpec cer)
                               throws IOException,
                                      InvalidRangeException

Deprecated. do not use.

Specified by:

readSection in interface IOServiceProvider

Throws:

IOException

InvalidRangeException

getStructureIterator

@Deprecated
public StructureDataIterator getStructureIterator(Structure s,
                                                               int bufferSize)

Deprecated. do not use.

Specified by:

getStructureIterator in interface IOServiceProvider

getStructureDataArrayIterator

public Iterator<StructureData> getStructureDataArrayIterator(Sequence s,
                                                             int bufferSize)

Description copied from interface: IOServiceProvider

Get the structure iterator. Iosps with top level sequences must override.

Specified by:

getStructureDataArrayIterator in interface IOServiceProvider

Parameters:

s - the Structure

bufferSize - the buffersize, may be -1 for default.

Returns:

an iterator over the StructureData

sendIospMessage

@Nullable
public Object sendIospMessage(@Nullable
                                         Object message)

Description copied from interface: IOServiceProvider

A way to communicate arbitrary information to and from an iosp.

Specified by:

sendIospMessage in interface IOServiceProvider

Parameters:

message - opaque message sent to the IOSP object when its opened (not when isValidFile() is called)

Returns:

opaque Object, may be null.

getLastModified

public long getLastModified()

Returns the time that the underlying file(s) were last modified. If they've changed since they were stored in the cache, they will be closed and reopened with FileFactory.

Specified by:

getLastModified in interface IOServiceProvider

Returns:

a long value representing the time the file(s) were last modified or 0L if the last-modified time couldn't be determined for any reason.

toStringDebug

public String toStringDebug(Object o)

Description copied from interface: IOServiceProvider

Debug info for this object.

Specified by:

toStringDebug in interface IOServiceProvider

Parameters:

o - which object

Returns:

debug info for this object

getDetailInfo

public String getDetailInfo()

Description copied from interface: IOServiceProvider

Show debug / underlying implementation details

Specified by:

getDetailInfo in interface IOServiceProvider

Returns:

debug info

getFileTypeVersion

public String getFileTypeVersion()

Description copied from interface: IOServiceProvider

Get the version of this file type.

Specified by:

getFileTypeVersion in interface IOServiceProvider

Returns:

version of the file type

See Also:

"https://www.unidata.ucar.edu/software/netcdf-java/formats/FileTypes.html"