ValueLobDb (H2 Database Engine wt-1.0.1 API)

java.lang.Object
- org.h2.value.Value
- - org.h2.value.ValueLobDb

所有已实现的接口:

Value.ValueBlob, Value.ValueClob
```
public class ValueLobDb
extends Value
implements Value.ValueClob, Value.ValueBlob
```
A implementation of the BLOB and CLOB data types. Small objects are kept in memory and stored in the record. Large objects are either stored in the database, or in temporary files.

嵌套类概要
- 从类继承的嵌套类/接口 org.h2.value.Value
  Value.ValueBlob, Value.ValueClob

字段概要
- 从类继承的字段 org.h2.value.Value
  ARRAY, BLOB, BOOLEAN, BYTE, BYTES, CLOB, DATE, DECIMAL, DOUBLE, FLOAT, GEOMETRY, INT, JAVA_OBJECT, LONG, NULL, RESULT_SET, SHORT, STRING, STRING_FIXED, STRING_IGNORECASE, TIME, TIMESTAMP, TIMESTAMP_TZ, TYPE_COUNT, UNKNOWN, UUID

方法概要

所有方法静态方法实例方法具体方法
限定符和类型	方法和说明
`protected int`	`compareSecure(Value v, CompareMode mode)` Compare the value with another value of the same type.
`Value`	`convertPrecision(long precision, boolean force)` Convert the precision to the requested value.
`Value`	`convertTo(int t)` Convert a lob to another data type.
`Value`	`copy(DataHandler database, int tableId)` Copy a large value, to be used in the given table.
`ValueLobDb`	`copyToResult()` Create an independent copy of this value, that will be bound to a result.
`ValueLobDb`	`copyToTemp()` Create an independent copy of this temporary value.
`static ValueLobDb`	`create(int type, DataHandler handler, int tableId, long id, byte[] hmac, long precision)` Create a LOB value.
`static Value`	`createSmallLob(int type, byte[] small)` Create a LOB object that fits in memory.
`static ValueLobDb`	`createSmallLob(int type, byte[] small, long precision)` Create a LOB object that fits in memory.
`static ValueLobDb`	`createTempBlob(InputStream in, long length, DataHandler handler)` Create a temporary BLOB value from a stream.
`static ValueLobDb`	`createTempClob(Reader in, long length, DataHandler handler)` Create a temporary CLOB value from a stream.
`boolean`	`equals(Object other)` Check if the two values have the same hash code.
`byte[]`	`getBytes()`
`byte[]`	`getBytesNoCopy()`
`int`	`getDisplaySize()` Get the display size in characters.
`InputStream`	`getInputStream()`
`long`	`getLobId()`
`int`	`getMemory()` Get the memory used by this object.
`Object`	`getObject()` Get the value as an object.
`long`	`getPrecision()` Get the precision.
`Reader`	`getReader()`
`byte[]`	`getSmall()` Get the data if this a small lob value.
`String`	`getSQL()` Get the SQL expression for this value.
`String`	`getString()` Get the value as a string.
`int`	`getTableId()` Get the current table id of this lob.
`String`	`getTraceSQL()` Get a medium size SQL expression for debugging or tracing.
`int`	`getType()` Get the value type.
`int`	`hashCode()`
`boolean`	`isLinkedToTable()` Check if this value is linked to a specific table.
`boolean`	`isRecoveryReference()`
`boolean`	`isStored()`
`void`	`remove()` Remove the underlying resource, if any.
`void`	`set(PreparedStatement prep, int parameterIndex)` Set the value as a parameter in a prepared statement.
`void`	`setRecoveryReference(boolean isRecoveryReference)`
`String`	`toString()`

从类继承的方法 org.h2.value.Value
add, checkPrecision, clearCache, compareTo, compareTypeSafe, convertScale, divide, getBigDecimal, getBoolean, getByte, getDataHandler, getDate, getDouble, getFloat, getHigherOrder, getInt, getLong, getResultSet, getScale, getShort, getSignum, getTime, getTimestamp, modulus, multiply, negate, subtract, throwUnsupportedExceptionForType

从类继承的方法 java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- 方法详细资料
  - create
```
public static ValueLobDb create(int type,
                                DataHandler handler,
                                int tableId,
                                long id,
                                byte[] hmac,
                                long precision)
```
    Create a LOB value.
    
    参数:
    
    type - the type
    
    handler - the data handler
    
    tableId - the table id
    
    id - the lob id
    
    hmac - the message authentication code
    
    precision - the precision (number of bytes / characters)
    
    返回:
    
    the 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.
    
    覆盖:
    
    convertTo 在类中 Value
    
    参数:
    
    t - the new type
    
    返回:
    
    the converted value
  - isLinkedToTable
```
public boolean isLinkedToTable()
```
    从类复制的说明: Value
    
    Check if this value is linked to a specific table. For values that are kept fully in memory, this method returns false.
    
    覆盖:
    
    isLinkedToTable 在类中 Value
    
    返回:
    
    true if it is
  - isStored
```
public boolean isStored()
```
  - remove
```
public void remove()
```
    从类复制的说明: Value
    
    Remove the underlying resource, if any. For values that are kept fully in memory this method has no effect.
    
    覆盖:
    
    remove 在类中 Value
  - copy
```
public Value copy(DataHandler database,
                  int tableId)
```
    从类复制的说明: Value
    
    Copy a large value, to be used in the given table. For values that are kept fully in memory this method has no effect.
    
    覆盖:
    
    copy 在类中 Value
    
    参数:
    
    database - the data handler
    
    tableId - the table where this object is used
    
    返回:
    
    the new value or itself
  - getTableId
```
public int getTableId()
```
    Get the current table id of this lob.
    
    覆盖:
    
    getTableId 在类中 Value
    
    返回:
    
    the table id
  - getType
```
public int getType()
```
    从类复制的说明: Value
    
    Get the value type.
    
    指定者:
    
    getType 在类中 Value
    
    返回:
    
    the type
  - getPrecision
```
public long getPrecision()
```
    从类复制的说明: Value
    
    Get the precision.
    
    指定者:
    
    getPrecision 在类中 Value
    
    返回:
    
    the precision
  - getString
```
public String getString()
```
    从类复制的说明: Value
    
    Get the value as a string.
    
    指定者:
    
    getString 在类中 Value
    
    返回:
    
    the string
  - getBytes
```
public byte[] getBytes()
```
    覆盖:
    
    getBytes 在类中 Value
  - getBytesNoCopy
```
public byte[] getBytesNoCopy()
```
    覆盖:
    
    getBytesNoCopy 在类中 Value
  - hashCode
```
public int hashCode()
```
    指定者:
    
    hashCode 在类中 Value
  - compareSecure
```
protected int compareSecure(Value v,
                            CompareMode mode)
```
    从类复制的说明: Value
    
    Compare the value with another value of the same type.
    
    指定者:
    
    compareSecure 在类中 Value
    
    参数:
    
    v - the other value
    
    mode - the compare mode
    
    返回:
    
    0 if both values are equal, -1 if the other value is smaller, and 1 otherwise
  - getObject
```
public Object getObject()
```
    从类复制的说明: Value
    
    Get the value as an object.
    
    指定者:
    
    getObject 在类中 Value
    
    返回:
    
    the object
  - getReader
```
public Reader getReader()
```
    覆盖:
    
    getReader 在类中 Value
  - getInputStream
```
public InputStream getInputStream()
```
    覆盖:
    
    getInputStream 在类中 Value
  - set
```
public void set(PreparedStatement prep,
                int parameterIndex)
         throws SQLException
```
    从类复制的说明: Value
    
    Set the value as a parameter in a prepared statement.
    
    指定者:
    
    set 在类中 Value
    
    参数:
    
    prep - the prepared statement
    
    parameterIndex - the parameter index
    
    抛出:
    
    SQLException
  - getSQL
```
public String getSQL()
```
    从类复制的说明: Value
    
    Get the SQL expression for this value.
    
    指定者:
    
    getSQL 在类中 Value
    
    返回:
    
    the SQL expression
  - getTraceSQL
```
public String getTraceSQL()
```
    从类复制的说明: 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.
    
    覆盖:
    
    getTraceSQL 在类中 Value
    
    返回:
    
    the SQL expression
  - getSmall
```
public byte[] getSmall()
```
    Get the data if this a small lob value.
    
    覆盖:
    
    getSmall 在类中 Value
    
    返回:
    
    the data
  - getDisplaySize
```
public int getDisplaySize()
```
    从类复制的说明: Value
    
    Get the display size in characters.
    
    指定者:
    
    getDisplaySize 在类中 Value
    
    返回:
    
    the display size
  - equals
```
public boolean equals(Object other)
```
    从类复制的说明: 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.
    
    指定者:
    
    equals 在类中 Value
    
    参数:
    
    other - the other value
    
    返回:
    
    true if they are equal
  - getMemory
```
public int getMemory()
```
    从类复制的说明: Value
    
    Get the memory used by this object.
    
    覆盖:
    
    getMemory 在类中 Value
    
    返回:
    
    the memory used in bytes
  - copyToTemp
```
public ValueLobDb copyToTemp()
```
    Create an independent copy of this temporary value. The file will not be deleted automatically.
    
    覆盖:
    
    copyToTemp 在类中 Value
    
    返回:
    
    the value
  - copyToResult
```
public ValueLobDb copyToResult()
```
    Create an independent copy of this value, that will be bound to a result.
    
    覆盖:
    
    copyToResult 在类中 Value
    
    返回:
    
    the value (this for small objects)
  - getLobId
```
public long getLobId()
```
  - toString
```
public String toString()
```
    覆盖:
    
    toString 在类中 Value
  - createTempClob
```
public static ValueLobDb createTempClob(Reader in,
                                        long length,
                                        DataHandler handler)
```
    Create a temporary CLOB value from a stream.
    
    参数:
    
    in - the reader
    
    length - the number of characters to read, or -1 for no limit
    
    handler - the data handler
    
    返回:
    
    the lob value
  - createTempBlob
```
public static ValueLobDb createTempBlob(InputStream in,
                                        long length,
                                        DataHandler handler)
```
    Create a temporary BLOB value from a stream.
    
    参数:
    
    in - the input stream
    
    length - the number of characters to read, or -1 for no limit
    
    handler - the data handler
    
    返回:
    
    the lob value
  - convertPrecision
```
public Value convertPrecision(long precision,
                              boolean force)
```
    从类复制的说明: Value
    
    Convert the precision to the requested value. The precision of the returned value may be somewhat larger than requested, because values with a fixed precision are not truncated.
    
    覆盖:
    
    convertPrecision 在类中 Value
    
    参数:
    
    precision - the new precision
    
    force - true if losing numeric precision is allowed
    
    返回:
    
    the new value
  - createSmallLob
```
public static Value createSmallLob(int type,
                                   byte[] small)
```
    Create a LOB object that fits in memory.
    
    参数:
    
    type - the type (Value.BLOB or CLOB)
    
    small - the byte array
    
    返回:
    
    the LOB
  - createSmallLob
```
public static ValueLobDb createSmallLob(int type,
                                        byte[] small,
                                        long precision)
```
    Create a LOB object that fits in memory.
    
    参数:
    
    type - the type (Value.BLOB or CLOB)
    
    small - the byte array
    
    precision - the precision
    
    返回:
    
    the LOB
  - setRecoveryReference
```
public void setRecoveryReference(boolean isRecoveryReference)
```
  - isRecoveryReference
```
public boolean isRecoveryReference()
```

类 ValueLobDb

嵌套类概要

从类继承的嵌套类/接口 org.h2.value.Value

字段概要

从类继承的字段 org.h2.value.Value

方法概要

从类继承的方法 org.h2.value.Value

从类继承的方法 java.lang.Object

方法详细资料

create

convertTo

isLinkedToTable

isStored

remove

copy

getTableId

getType

getPrecision

getString

getBytes

getBytesNoCopy

hashCode

compareSecure

getObject

getReader

getInputStream

set

getSQL

getTraceSQL

getSmall

getDisplaySize

equals

getMemory

copyToTemp

copyToResult

getLobId

toString

createTempClob

createTempBlob

convertPrecision

createSmallLob

createSmallLob

setRecoveryReference

isRecoveryReference