org.h2.value
Class ValueLobDb

java.lang.Object
  extended by org.h2.value.Value
      extended by org.h2.value.ValueLobDb
All Implemented Interfaces:
Value.ValueBlob, Value.ValueClob

public class ValueLobDb
extends Value
implements Value.ValueClob, Value.ValueBlob

An alternate LOB implementation.


Nested Class Summary
 
Nested classes/interfaces inherited from class org.h2.value.Value
Value.ValueBlob, Value.ValueClob
 
Field Summary
 
Fields inherited from class org.h2.value.Value
ARRAY, BLOB, BOOLEAN, BYTE, BYTES, CLOB, DATE, DECIMAL, DOUBLE, FLOAT, INT, JAVA_OBJECT, LONG, NULL, RESULT_SET, SHORT, STRING, STRING_FIXED, STRING_IGNORECASE, TIME, TIMESTAMP, TYPE_COUNT, UNKNOWN, UUID
 
Method Summary
 void close()
          Close the underlying resource, if any.
protected  int compareSecure(Value v, CompareMode mode)
          Compare the value with another value of the same type.
 Value convertTo(int t)
          Convert a lob to another data type.
 ValueLobDb copyToTemp()
          Create an independent copy of this temporary value.
static ValueLobDb create(int type, LobStorage lobStorage, java.lang.String fileName, int tableId, long id, long precision)
          Create a LOB value.
static ValueLobDb createSmallLob(int type, byte[] small, long precision)
          Create a small lob using the given byte array.
static ValueLobDb createTempBlob(java.io.InputStream in, long length, DataHandler handler)
          Create a temporary BLOB value from a stream.
static ValueLobDb createTempClob(java.io.Reader in, long length, DataHandler handler)
          Create a temporary CLOB value from a stream.
 boolean equals(java.lang.Object other)
          Check if the two values have the same hash code.
 byte[] getBytes()
           
 byte[] getBytesNoCopy()
           
 int getDisplaySize()
          Get the display size in characters.
 java.io.InputStream getInputStream()
           
 long getLobId()
           
 int getMemory()
          Get the memory used by this object.
 java.lang.Object getObject()
          Get the value as an object.
 long getPrecision()
          Get the precision.
 java.io.Reader getReader()
           
 byte[] getSmall()
          Get the data if this a small lob value.
 java.lang.String getSQL()
          Get the SQL expression for this value.
 java.lang.String getString()
          Get the value as a string.
 int getTableId()
          Get the current table id of this lob.
 java.lang.String getTraceSQL()
          Get a medium size SQL expression for debugging or tracing.
 int getType()
          Get the value type.
 int hashCode()
           
 boolean isFileBased()
          Check if this value is stored in it's own file.
 boolean isLinked()
          Check if this value is linked to a specific table.
 Value link(DataHandler h, int tabId)
          Link a large value to a given table.
 void set(java.sql.PreparedStatement prep, int parameterIndex)
          Set the value as a parameter in a prepared statement.
 void setPrecision(long precision)
           
 java.lang.String toString()
           
 void unlink()
          Mark any underlying resource as 'not linked to any table'.
 
Methods inherited from class org.h2.value.Value
add, checkPrecision, clearCache, compareTo, compareTypeSave, convertPrecision, convertScale, divide, getBigDecimal, getBoolean, getByte, getDate, getDateNoCopy, getDouble, getFloat, getHigherOrder, getInt, getLong, getScale, getShort, getSignum, getTime, getTimeNoCopy, getTimestamp, getTimestampNoCopy, multiply, negate, subtract, throwUnsupportedExceptionForType
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Method Detail

create

public static ValueLobDb create(int type,
                                LobStorage lobStorage,
                                java.lang.String fileName,
                                int tableId,
                                long id,
                                long precision)
Create a LOB value.

Parameters:
type - the type
lobStorage - the storage
fileName - the file name (may be null)
tableId - the table id
id - the lob id
precision - the precision (number of bytes / characters)
Returns:
the value

createSmallLob

public static ValueLobDb createSmallLob(int type,
                                        byte[] small,
                                        long precision)
Create a small lob using the given byte array.

Parameters:
type - the type (Value.BLOB or CLOB)
small - the byte array
precision - the precision
Returns:
the lob value

convertTo

public Value convertTo(int t)
Convert a lob to another data type. The data is fully read in memory except when converting to BLOB or CLOB.

Overrides:
convertTo in class Value
Parameters:
t - the new type
Returns:
the converted value

isLinked

public boolean isLinked()
Description copied from class: Value
Check if this value is linked to a specific table. For values that are kept fully in memory, this method returns false.

Overrides:
isLinked in class Value
Returns:
true if it is

close

public void close()
Description copied from class: Value
Close the underlying resource, if any. For values that are kept fully in memory this method has no effect.

Overrides:
close in class Value

unlink

public void unlink()
Description copied from class: Value
Mark any underlying resource as 'not linked to any table'. For values that are kept fully in memory this method has no effect.

Overrides:
unlink in class Value

link

public Value link(DataHandler h,
                  int tabId)
Description copied from class: Value
Link a large value to a given table. For values that are kept fully in memory this method has no effect.

Overrides:
link in class Value
Parameters:
h - the data handler
tabId - the table to link to
Returns:
the new value or itself

getTableId

public int getTableId()
Get the current table id of this lob.

Overrides:
getTableId in class Value
Returns:
the table id

getType

public int getType()
Description copied from class: Value
Get the value type.

Specified by:
getType in class Value
Returns:
the type

getPrecision

public long getPrecision()
Description copied from class: Value
Get the precision.

Specified by:
getPrecision in class Value
Returns:
the precision

getString

public java.lang.String getString()
Description copied from class: Value
Get the value as a string.

Specified by:
getString in class Value
Returns:
the string

getBytes

public byte[] getBytes()
Overrides:
getBytes in class Value

getBytesNoCopy

public byte[] getBytesNoCopy()
Overrides:
getBytesNoCopy in class Value

hashCode

public int hashCode()
Specified by:
hashCode in class Value

compareSecure

protected int compareSecure(Value v,
                            CompareMode mode)
Description copied from class: Value
Compare the value with another value of the same type.

Specified by:
compareSecure in class Value
Parameters:
v - the other value
mode - the compare mode
Returns:
0 if both values are equal, -1 if the other value is smaller, and 1 otherwise

getObject

public java.lang.Object getObject()
Description copied from class: Value
Get the value as an object.

Specified by:
getObject in class Value
Returns:
the object

getReader

public java.io.Reader getReader()
Overrides:
getReader in class Value

getInputStream

public java.io.InputStream getInputStream()
Overrides:
getInputStream in class Value

set

public void set(java.sql.PreparedStatement prep,
                int parameterIndex)
         throws java.sql.SQLException
Description copied from class: Value
Set the value as a parameter in a prepared statement.

Specified by:
set in class Value
Parameters:
prep - the prepared statement
parameterIndex - the parameter index
Throws:
java.sql.SQLException

getSQL

public java.lang.String getSQL()
Description copied from class: Value
Get the SQL expression for this value.

Specified by:
getSQL in class Value
Returns:
the SQL expression

getTraceSQL

public java.lang.String getTraceSQL()
Description copied from class: Value
Get a medium size SQL expression for debugging or tracing. If the precision is too large, only a subset of the value is returned.

Overrides:
getTraceSQL in class Value
Returns:
the SQL expression

getSmall

public byte[] getSmall()
Get the data if this a small lob value.

Overrides:
getSmall in class Value
Returns:
the data

getDisplaySize

public int getDisplaySize()
Description copied from class: Value
Get the display size in characters.

Specified by:
getDisplaySize in class Value
Returns:
the display size

equals

public boolean equals(java.lang.Object other)
Description copied from class: Value
Check if the two values have the same hash code. No data conversion is made; this method returns false if the other object is not of the same class. For some values, compareTo may return 0 even if equals return false. Example: ValueDecimal 0.0 and 0.00.

Specified by:
equals in class Value
Parameters:
other - the other value
Returns:
true if they are equal

isFileBased

public boolean isFileBased()
Description copied from class: Value
Check if this value is stored in it's own file. For values that are kept fully in memory, this method returns false.

Overrides:
isFileBased in class Value
Returns:
true if it is

getMemory

public int getMemory()
Description copied from class: Value
Get the memory used by this object.

Overrides:
getMemory in class Value
Returns:
the memory used in bytes

copyToTemp

public ValueLobDb copyToTemp()
Create an independent copy of this temporary value. The file will not be deleted automatically.

Overrides:
copyToTemp in class Value
Returns:
the value

getLobId

public long getLobId()

setPrecision

public void setPrecision(long precision)

toString

public java.lang.String toString()
Overrides:
toString in class Value

createTempClob

public static ValueLobDb createTempClob(java.io.Reader in,
                                        long length,
                                        DataHandler handler)
Create a temporary CLOB value from a stream.

Parameters:
in - the reader
length - the number of characters to read, or -1 for no limit
handler - the data handler
Returns:
the lob value

createTempBlob

public static ValueLobDb createTempBlob(java.io.InputStream in,
                                        long length,
                                        DataHandler handler)
Create a temporary BLOB value from a stream.

Parameters:
in - the input stream
length - the number of characters to read, or -1 for no limit
handler - the data handler
Returns:
the lob value