Package ucar.nc2

Class NetcdfFiles

java.lang.Object

ucar.nc2.NetcdfFiles

public class NetcdfFiles
extends Object

Static helper methods for NetcdfFile objects. These use builders and new versions of Iosp's when available.

Since:

10/3/2019.

Field Summary

Fields

Modifier and Type	Field	Description
static String	reservedFullName

Method Summary

Modifier and Type	Method	Description
static NetcdfFile	build(IOServiceProvider spi, RandomAccessFile raf, String location, CancelTask cancelTask)
static boolean	canOpen(String location)	Find out if the location can be opened, but dont actually open it.
static String	makeFullName(Group g)	Create a Groups's full name with appropriate backslash escaping.
static String	makeFullName(Variable v)	Create a Variable's full name with appropriate backslash escaping.
static String	makeFullNameSectionSpec(Variable v)	Create a Variable's full name with appropriate backslash escaping for use in a section spec.
static String	makeNameUnescaped(String vname)	Unescape any escaped characters in a name.
static String	makeValidCDLName(String vname)	Escape special characters in a netcdf short name when it is intended for use in CDL.
static String	makeValidCdmObjectName(String shortName)	Create a valid CDM object name.
static String	makeValidPathName(String vname)	Escape special characters in a netcdf short name when it is intended for use in a fullname
static NetcdfFile	open(String location)	Open an existing netcdf file (read only).
static NetcdfFile	open(String location, int buffer_size, CancelTask cancelTask)	Open an existing file (read only), with option of cancelling, setting the RandomAccessFile buffer size for efficiency.
static NetcdfFile	open(String location, int buffer_size, CancelTask cancelTask, Object iospMessage)	Open an existing file (read only), with option of cancelling, setting the RandomAccessFile buffer size for efficiency, with an optional special object for the iosp.
static NetcdfFile	open(String location, String iospClassName, int bufferSize, CancelTask cancelTask, Object iospMessage)	Open an existing file (read only), specifying which IOSP is to be used.
static NetcdfFile	open(String location, CancelTask cancelTask)	Open an existing file (read only), with option of cancelling.
static NetcdfFile	open(RandomAccessFile raf, String location, CancelTask cancelTask, Object iospMessage)	Open a RandomAccessFile as a NetcdfFile, if possible.
static NetcdfFile	openInMemory(String filename)	Read a local CDM file into memory.
static NetcdfFile	openInMemory(String name, byte[] data)	Open an in-memory netcdf file.
static NetcdfFile	openInMemory(String name, byte[] data, String iospClassName)	Open an in-memory netcdf file, with a specific iosp.
static NetcdfFile	openInMemory(URI uri)	Read a remote CDM file into memory.
static void	registerIOProvider(Class<?> iospClass)	Register an IOServiceProvider.
static void	registerIOProvider(String className)	Register an IOServiceProvider, using its class string name.

Methods inherited from class java.lang.Object

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

Field Detail

reservedFullName

public static final String reservedFullName

See Also:

Constant Field Values

Method Detail

registerIOProvider

public static void registerIOProvider(String className)
                               throws NoSuchMethodException,
                                      InvocationTargetException,
                                      InstantiationException,
                                      IllegalAccessException,
                                      ClassNotFoundException

Register an IOServiceProvider, using its class string name.

Parameters:

className - Class that implements IOServiceProvider.

Throws:

IllegalAccessException - if class is not accessible.

InstantiationException - if class doesnt have a no-arg constructor.

ClassNotFoundException - if class not found.

NoSuchMethodException

InvocationTargetException

registerIOProvider

public static void registerIOProvider(Class<?> iospClass)
                               throws NoSuchMethodException,
                                      InvocationTargetException,
                                      InstantiationException,
                                      IllegalAccessException

Register an IOServiceProvider. A new instance will be created when one of its files is opened.

Parameters:

iospClass - Class that implements IOServiceProvider.

Throws:

NoSuchMethodException

InvocationTargetException

InstantiationException

IllegalAccessException

open

public static NetcdfFile open(String location)
                       throws IOException

Open an existing netcdf file (read only).

Parameters:

location - location of file.

Returns:

the NetcdfFile.

Throws:

IOException - if error

open

public static NetcdfFile open(String location,
                              CancelTask cancelTask)
                       throws IOException

Open an existing file (read only), with option of cancelling.

Parameters:

location - location of the file.

cancelTask - allow task to be cancelled; may be null.

Returns:

NetcdfFile object, or null if cant find IOServiceProver

Throws:

IOException - if error

open

public static NetcdfFile open(String location,
                              int buffer_size,
                              CancelTask cancelTask)
                       throws IOException

Open an existing file (read only), with option of cancelling, setting the RandomAccessFile buffer size for efficiency.

Parameters:

location - location of file.

buffer_size - RandomAccessFile buffer size, if ≤ 0, use default size

cancelTask - allow task to be cancelled; may be null.

Returns:

NetcdfFile object, or null if cant find IOServiceProver

Throws:

IOException - if error

open

public static NetcdfFile open(String location,
                              int buffer_size,
                              CancelTask cancelTask,
                              Object iospMessage)
                       throws IOException

Open an existing file (read only), with option of cancelling, setting the RandomAccessFile buffer size for efficiency, with an optional special object for the iosp.

Parameters:

location - location of file. This may be a

1. local netcdf-3 filename (with a file: prefix or no prefix)
2. remote netcdf-3 filename (with an http: prefix)
3. local netcdf-4 filename (with a file: prefix or no prefix)
4. local hdf-5 filename (with a file: prefix or no prefix)
5. local iosp filename (with a file: prefix or no prefix)

If file ends with ".Z", ".zip", ".gzip", ".gz", or ".bz2", it will uncompress/unzip and write to new file without the suffix, then use the uncompressed file. It will look for the uncompressed file before it does any of that. Generally it prefers to place the uncompressed file in the same directory as the original file. If it does not have write permission on that directory, it will use the directory defined by ucar.nc2.util.DiskCache class.

buffer_size - RandomAccessFile buffer size, if ≤ 0, use default size

cancelTask - allow task to be cancelled; may be null.

iospMessage - special iosp tweaking (sent before open is called), may be null

Returns:

NetcdfFile object, or null if cant find IOServiceProver

Throws:

IOException - if error

open

public static NetcdfFile open(String location,
                              String iospClassName,
                              int bufferSize,
                              CancelTask cancelTask,
                              Object iospMessage)
                       throws ClassNotFoundException,
                              NoSuchMethodException,
                              InvocationTargetException,
                              InstantiationException,
                              IllegalAccessException,
                              IOException

Open an existing file (read only), specifying which IOSP is to be used.

Parameters:

location - location of file

iospClassName - fully qualified class name of the IOSP class to handle this file

bufferSize - RandomAccessFile buffer size, if ≤ 0, use default size

cancelTask - allow task to be cancelled; may be null.

iospMessage - special iosp tweaking (sent before open is called), may be null

Returns:

NetcdfFile object, or null if cant find IOServiceProver

Throws:

ClassNotFoundException

NoSuchMethodException

InvocationTargetException

InstantiationException

IllegalAccessException

IOException

canOpen

public static boolean canOpen(String location)

Find out if the location can be opened, but dont actually open it. In order for a location to be openable by netCDF-java, we must have 1) a proper RandomAccessFile implementation, and 2) a proper IOServiceProvider implementation.

Parameters:

location - location of file

Returns:

true if can be opened

openInMemory

public static NetcdfFile openInMemory(String filename)
                               throws IOException

Read a local CDM file into memory. All reads are then done from memory.

Parameters:

filename - location of CDM file, must be a local file.

Returns:

a NetcdfFile, which is completely in memory

Throws:

IOException - if error reading file

openInMemory

public static NetcdfFile openInMemory(URI uri)
                               throws IOException

Read a remote CDM file into memory. All reads are then done from memory.

Parameters:

uri - location of CDM file, must be accessible through url.toURL().openStream().

Returns:

a NetcdfFile, which is completely in memory

Throws:

IOException - if error reading file

openInMemory

public static NetcdfFile openInMemory(String name,
                                      byte[] data)
                               throws IOException

Open an in-memory netcdf file.

Parameters:

name - name of the dataset. Typically use the filename or URI.

data - in-memory netcdf file

Returns:

memory-resident NetcdfFile

Throws:

IOException

openInMemory

public static NetcdfFile openInMemory(String name,
                                      byte[] data,
                                      String iospClassName)
                               throws IOException,
                                      ClassNotFoundException,
                                      IllegalAccessException,
                                      InstantiationException,
                                      NoSuchMethodException,
                                      InvocationTargetException

Open an in-memory netcdf file, with a specific iosp.

Parameters:

name - name of the dataset. Typically use the filename or URI.

data - in-memory netcdf file

iospClassName - fully qualified class name of the IOSP class to handle this file

Returns:

NetcdfFile object, or null if cant find IOServiceProver

Throws:

IOException

ClassNotFoundException

IllegalAccessException

InstantiationException

NoSuchMethodException

InvocationTargetException

open

public static NetcdfFile open(RandomAccessFile raf,
                              String location,
                              @Nullable
                              CancelTask cancelTask,
                              @Nullable
                              Object iospMessage)
                       throws IOException

Open a RandomAccessFile as a NetcdfFile, if possible.

Parameters:

raf - The open raf; is closed by this method onlu on IOException.

location - human readable location of this dataset.

cancelTask - used to monitor user cancellation; may be null.

iospMessage - send this message to iosp; may be null.

Returns:

NetcdfFile or throw an Exception.

Throws:

IOException

build

public static NetcdfFile build(IOServiceProvider spi,
                               RandomAccessFile raf,
                               String location,
                               CancelTask cancelTask)
                        throws IOException

Throws:

IOException

makeValidCdmObjectName

public static String makeValidCdmObjectName(String shortName)

Create a valid CDM object name. Control chars (< 0x20) are not allowed. Trailing and leading blanks are not allowed and are stripped off. A space is converted into an underscore "_". A forward slash "/" is converted into an underscore "_".

Parameters:

shortName - from this name

Returns:

valid CDM object name

makeValidCDLName

public static String makeValidCDLName(String vname)

Escape special characters in a netcdf short name when it is intended for use in CDL.

Parameters:

vname - the name

Returns:

escaped version of it

makeValidPathName

public static String makeValidPathName(String vname)

Escape special characters in a netcdf short name when it is intended for use in a fullname

Parameters:

vname - the name

Returns:

escaped version of it

makeNameUnescaped

public static String makeNameUnescaped(String vname)

Unescape any escaped characters in a name.

Parameters:

vname - the escaped name

Returns:

unescaped version of it

makeFullName

public static String makeFullName(Group g)

Create a Groups's full name with appropriate backslash escaping.

makeFullName

public static String makeFullName(Variable v)

Create a Variable's full name with appropriate backslash escaping. Warning: do not use for a section spec.

Parameters:

v - the Variable

Returns:

full name

makeFullNameSectionSpec

public static String makeFullNameSectionSpec(Variable v)

Create a Variable's full name with appropriate backslash escaping for use in a section spec.

Parameters:

v - the cdm node

Returns:

full name