java.lang.Object
- java.io.Reader
- - com.compuware.api.topaz.hostresources.zos.DataSetReader

All Implemented Interfaces:

Closeable, AutoCloseable, Readable
```
public final class DataSetReader
extends Reader
```
Reads text from a z/OS dataset, providing for the efficient reading of characters.
The entire content of the dataset will be obtained at the moment the DataSetReader is constructed and stored in a temporary file. Therefore, any reads done on that DataSetReader object will reflect the content of the dataset at the moment the DataSetReader object was constructed, rather than the content of the dataset at the moment the of read. When close is called, the temporary file will be deleted.
The text returned will be in UTF-8 encoding. Non-displayable binary data will be substituted with Unicode characters that are outside of the code page of the mainframe host login. This allows us to distinguish text data from binary within UTF-8, and if the data is written back to the mainframe using a DataSetWriter, those Unicode characters will be replaced with the corresponding binary bytes.
For efficient reading of dataset records, it is advisable to wrap a BufferedReader around a DataSetReader. For example,
BufferedReader in = new BufferedReader(new DataSetReader(...));
Regarding parameter validation for the methods within this class:
A dataset name is considered invalid if:
- The total length of the name is 0 or is greater than 44 characters.
- The length of any qualifier within the name is 0 or is greater than 8 characters.
- Qualifiers are delimited by anything other than a '.' character.
- Any characters outside of the code page 1047 hex values for A-Z, a-z, 0-9, @, #, $, or - are present.
- Any qualifier (and hence the name itself) starts with a digit (0-9) or a hyphen (-).
Since:

1.0.0

Version:

2.0.0

See Also:

ISequentialDataSet

Restriction:

This class is not intended to be extended by clients.

Constructor Summary

Constructors
Constructor	Description
`DataSetReader(IZOSHostConnection zosHostConnection, String sequentialDataSetName)`	Constructs a `DataSetReader` using the specified z/OS host connection and sequential dataset name.
`DataSetReader(ISequentialDataSet sequentialDataSet)`	Constructs a `DataSetReader` using the specified sequential dataset.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`
`boolean`	`containsNonDisplayableData()`	Returns whether non-displayable binary data exists within the text of this reader.
`char`	`getReplacementCharacter()`	Returns the replacement character for non-displayable binary data.
`int`	`read(char[] dataBuffer, int offset, int length)`

Methods inherited from class java.io.Reader
mark, markSupported, nullReader, read, read, read, ready, reset, skip, transferTo

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - DataSetReader
```
public DataSetReader(ISequentialDataSet sequentialDataSet)
              throws DataSetAccessException,
                     DataSetInUseException,
                     DataSetMigratedException,
                     DataSetNotFoundException
```
    Constructs a DataSetReader using the specified sequential dataset.
    This dataset reader can be used to read the content of the specified sequential dataset in UTF-8 characters. This is ideally used for reading sequential datasets that contain displayable characters.
    Non-displayable binary data will be substituted with a replacement character for display purposes.
    
    Parameters:
    
    sequentialDataSet - the sequential dataset to read
    
    Throws:
    
    IllegalArgumentException - if sequentialDataSet is null
    
    HostIOException - if an IOException occurs reading the dataset
    
    ZOSSystemException - if a z/OS system error occurs
    
    ZOSAbendException - if a z/OS ABEND occurs
    
    DataSetAccessException - if the user's credentials do not grant access authority for the sequential dataset
    
    DataSetInUseException - if an exclusive enqueue exists on the sequential dataset
    
    DataSetMigratedException - if the sequential dataset is migrated (this may occur if the dataset is migrated after it is retrieved from the z/OS host)
    
    DataSetNotFoundException - if the sequential dataset no longer exists (this may occur if the dataset is deleted after it is retrieved from the z/OS host)
    
    Since:
    
    1.0.0
    
    See Also:
    
    ISequentialDataSet
  - DataSetReader
```
public DataSetReader(IZOSHostConnection zosHostConnection,
                     String sequentialDataSetName)
              throws DataSetAccessException,
                     DataSetInUseException,
                     DataSetMigratedException,
                     DataSetNotFoundException
```
    Constructs a DataSetReader using the specified z/OS host connection and sequential dataset name.
    This dataset reader can be used to read the content of the specified sequential dataset in UTF-8 characters. This is ideally used for reading sequential datasets that contain displayable characters.
    Non-displayable binary data will be substituted with a replacement character for display purposes.
    
    Parameters:
    
    zosHostConnection - a connection to the z/OS host on which the sequential dataset resides
    
    sequentialDataSetName - the name of the sequential dataset to read
    
    Throws:
    
    IllegalArgumentException - if zosHostConnection is null, or if sequentialDataSetName is null or invalid
    
    HostIOException - if an IOException occurs reading the sequential dataset
    
    HostNotConnectedException - if zosHostConnection is not connected
    
    ZOSSystemException - if a z/OS system error occurs
    
    ZOSAbendException - if a z/OS ABEND occurs
    
    DataSetAccessException - if the user's credentials do not grant access authority for the sequential dataset
    
    DataSetInUseException - if an exclusive enqueue exists on the sequential dataset
    
    DataSetMigratedException - if the sequential dataset is migrated
    
    DataSetNotFoundException - if the sequential dataset does not exist
    
    Since:
    
    1.0.0
    
    See Also:
    
    IZOSHostConnection
- Method Detail
  - containsNonDisplayableData
```
public boolean containsNonDisplayableData()
```
    Returns whether non-displayable binary data exists within the text of this reader.
    Non-displayable binary data is substituted with the replacement character for display purposes.
    
    Returns:
    
    true if non-displayable binary data exists, false otherwise
    
    Since:
    
    1.0.0
    
    See Also:
    
    getReplacementCharacter()
  - getReplacementCharacter
```
public char getReplacementCharacter()
```
    Returns the replacement character for non-displayable binary data.
    The replacement character is uFFFD (a lozenge).
    
    Returns:
    
    the replacement character
    
    Since:
    
    1.0.0
  - close
```
public void close()
           throws IOException
```
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in class Reader
    
    Throws:
    
    IOException
    
    Since:
    
    1.0.0
  - read
```
public int read(char[] dataBuffer,
                int offset,
                int length)
         throws IOException
```
    Specified by:
    
    read in class Reader
    
    Throws:
    
    IOException
    
    Since:
    
    1.0.0

Class DataSetReader

Constructor Summary

Method Summary

Methods inherited from class java.io.Reader

Methods inherited from class java.lang.Object

Constructor Detail

DataSetReader

DataSetReader

Method Detail

containsNonDisplayableData

getReplacementCharacter

close

read