Interface StructReader 

public interface StructReader

A base interface for reading the fields of a STRUCT. The Cloud Spanner yields StructReader instances as one of the subclasses ResultSet or Struct, most commonly as the result of a read or query operation. At any point in time, a StructReader provides access to a single tuple of data comprising multiple typed columns. Each column may have a NULL or non-NULL value; in both cases, columns always have a type.

Column values are accessed using the getTypeName() methods; a set of methods exists for each Java type that a column may be read as, and depending on the type of the column, only a subset of those methods will be appropriate. For example, #getString(int) and #getString(String) exist for reading columns of type Type#string(); attempting to call those methods for columns of other types will result in an IllegalStateException. The getTypeName() methods should only be called for non-NULL values, otherwise a NullPointerException is raised; #isNull(int)/#isNull(String) can be used to test for NULL-ness if necessary.

All methods for accessing a column have overloads that accept an int column index and a String column name. Column indices are zero-based. The column name overloads will fail with IllegalArgumentException if the column name does not appear exactly once in this instance's #getType(). The int overloads are typically more efficient than their String counterparts.

StructReader itself does not define whether the implementing type is mutable or immutable. For example, ResultSet is a mutable implementation of StructReader, where the StructReader methods provide access to the row that the result set is currently positioned over and ResultSet#next() changes that view to the next row, whereas Struct is an immutable implementation of StructReader.

Methods

getBigDecimal(int columnIndex)

public abstract BigDecimal getBigDecimal(int columnIndex)

Returns the value of a non-NULL column with type Type#numeric().

Parameter
Name Description
columnIndex int
Returns
Type Description
BigDecimal

getBigDecimal(String columnName)

public abstract BigDecimal getBigDecimal(String columnName)

Returns the value of a non-NULL column with type Type#numeric().

Parameter
Name Description
columnName String
Returns
Type Description
BigDecimal

getBigDecimalList(int columnIndex)

public abstract List<BigDecimal> getBigDecimalList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.numeric()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<BigDecimal>

getBigDecimalList(String columnName)

public abstract List<BigDecimal> getBigDecimalList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.numeric()).

Parameter
Name Description
columnName String
Returns
Type Description
List<BigDecimal>

getBoolean(int columnIndex)

public abstract boolean getBoolean(int columnIndex)

Returns the value of a non-NULL column with type Type#bool().

Parameter
Name Description
columnIndex int
Returns
Type Description
boolean

getBoolean(String columnName)

public abstract boolean getBoolean(String columnName)

Returns the value of a non-NULL column with type Type#bool().

Parameter
Name Description
columnName String
Returns
Type Description
boolean

getBooleanArray(int columnIndex)

public abstract boolean[] getBooleanArray(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.bool()).

Parameter
Name Description
columnIndex int
Returns
Type Description
boolean[]

getBooleanArray(String columnName)

public abstract boolean[] getBooleanArray(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.bool()).

Parameter
Name Description
columnName String
Returns
Type Description
boolean[]

getBooleanList(int columnIndex)

public abstract List<Boolean> getBooleanList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.bool()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<Boolean>

getBooleanList(String columnName)

public abstract List<Boolean> getBooleanList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.bool()).

Parameter
Name Description
columnName String
Returns
Type Description
List<Boolean>

getBytes(int columnIndex)

public abstract ByteArray getBytes(int columnIndex)

Returns the value of a non-NULL column with type Type#bytes().

Parameter
Name Description
columnIndex int
Returns
Type Description
com.google.cloud.ByteArray

getBytes(String columnName)

public abstract ByteArray getBytes(String columnName)

Returns the value of a non-NULL column with type Type#bytes().

Parameter
Name Description
columnName String
Returns
Type Description
com.google.cloud.ByteArray

getBytesList(int columnIndex)

public abstract List<ByteArray> getBytesList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.bytes()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<com.google.cloud.ByteArray>

getBytesList(String columnName)

public abstract List<ByteArray> getBytesList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.bytes()).

Parameter
Name Description
columnName String
Returns
Type Description
List<com.google.cloud.ByteArray>

getColumnCount()

public abstract int getColumnCount()

Returns the number of columns in the underlying data. This includes any columns with NULL values.

Returns
Type Description
int

getColumnIndex(String columnName)

public abstract int getColumnIndex(String columnName)

Returns the index of the column named columnName.

Parameter
Name Description
columnName String
Returns
Type Description
int

getColumnType(int columnIndex)

public abstract Type getColumnType(int columnIndex)

Returns the type of a column.

Parameter
Name Description
columnIndex int
Returns
Type Description
Type

getColumnType(String columnName)

public abstract Type getColumnType(String columnName)

Returns the type of a column.

Parameter
Name Description
columnName String
Returns
Type Description
Type

getDate(int columnIndex)

public abstract Date getDate(int columnIndex)

Returns the value of a non-NULL column with type Type#date().

Parameter
Name Description
columnIndex int
Returns
Type Description
com.google.cloud.Date

getDate(String columnName)

public abstract Date getDate(String columnName)

Returns the value of a non-NULL column with type Type#date().

Parameter
Name Description
columnName String
Returns
Type Description
com.google.cloud.Date

getDateList(int columnIndex)

public abstract List<Date> getDateList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.date()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<com.google.cloud.Date>

getDateList(String columnName)

public abstract List<Date> getDateList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.date()).

Parameter
Name Description
columnName String
Returns
Type Description
List<com.google.cloud.Date>

getDouble(int columnIndex)

public abstract double getDouble(int columnIndex)

Returns the value of a non-NULL column with type Type#float64().

Parameter
Name Description
columnIndex int
Returns
Type Description
double

getDouble(String columnName)

public abstract double getDouble(String columnName)

Returns the value of a non-NULL column with type Type#float64().

Parameter
Name Description
columnName String
Returns
Type Description
double

getDoubleArray(int columnIndex)

public abstract double[] getDoubleArray(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.float64()).

Parameter
Name Description
columnIndex int
Returns
Type Description
double[]

getDoubleArray(String columnName)

public abstract double[] getDoubleArray(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.float64()).

Parameter
Name Description
columnName String
Returns
Type Description
double[]

getDoubleList(int columnIndex)

public abstract List<Double> getDoubleList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.float64()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<Double>

getDoubleList(String columnName)

public abstract List<Double> getDoubleList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.float64()).

Parameter
Name Description
columnName String
Returns
Type Description
List<Double>

getJson(int columnIndex)

public default String getJson(int columnIndex)

Returns the value of a non-NULL column with type Type#string().

Parameter
Name Description
columnIndex int
Returns
Type Description
String

getJson(String columnName)

public default String getJson(String columnName)

Returns the value of a non-NULL column with type Type#string().

Parameter
Name Description
columnName String
Returns
Type Description
String

getJsonList(int columnIndex)

public default List<String> getJsonList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.string()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<String>

getJsonList(String columnName)

public default List<String> getJsonList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.string()).

Parameter
Name Description
columnName String
Returns
Type Description
List<String>

getLong(int columnIndex)

public abstract long getLong(int columnIndex)

Returns the value of a non-NULL column with type Type#int64().

Parameter
Name Description
columnIndex int
Returns
Type Description
long

getLong(String columnName)

public abstract long getLong(String columnName)

Returns the value of a non-NULL column with type Type#int64().

Parameter
Name Description
columnName String
Returns
Type Description
long

getLongArray(int columnIndex)

public abstract long[] getLongArray(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.int64()).

Parameter
Name Description
columnIndex int
Returns
Type Description
long[]

getLongArray(String columnName)

public abstract long[] getLongArray(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.int64()).

Parameter
Name Description
columnName String
Returns
Type Description
long[]

getLongList(int columnIndex)

public abstract List<Long> getLongList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.int64()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<Long>

getLongList(String columnName)

public abstract List<Long> getLongList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.int64()).

Parameter
Name Description
columnName String
Returns
Type Description
List<Long>

getString(int columnIndex)

public abstract String getString(int columnIndex)

Returns the value of a non-NULL column with type Type#string().

Parameter
Name Description
columnIndex int
Returns
Type Description
String

getString(String columnName)

public abstract String getString(String columnName)

Returns the value of a non-NULL column with type Type#string().

Parameter
Name Description
columnName String
Returns
Type Description
String

getStringList(int columnIndex)

public abstract List<String> getStringList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.string()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<String>

getStringList(String columnName)

public abstract List<String> getStringList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.string()).

Parameter
Name Description
columnName String
Returns
Type Description
List<String>

getStructList(int columnIndex)

public abstract List<Struct> getStructList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.struct(...)).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<Struct>

getStructList(String columnName)

public abstract List<Struct> getStructList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.struct(...)).

Parameter
Name Description
columnName String
Returns
Type Description
List<Struct>

getTimestamp(int columnIndex)

public abstract Timestamp getTimestamp(int columnIndex)

Returns the value of a non-NULL column with type Type#timestamp().

Parameter
Name Description
columnIndex int
Returns
Type Description
com.google.cloud.Timestamp

getTimestamp(String columnName)

public abstract Timestamp getTimestamp(String columnName)

Returns the value of a non-NULL column with type Type#timestamp().

Parameter
Name Description
columnName String
Returns
Type Description
com.google.cloud.Timestamp

getTimestampList(int columnIndex)

public abstract List<Timestamp> getTimestampList(int columnIndex)

Returns the value of a non-NULL column with type Type.array(Type.timestamp()).

Parameter
Name Description
columnIndex int
Returns
Type Description
List<com.google.cloud.Timestamp>

getTimestampList(String columnName)

public abstract List<Timestamp> getTimestampList(String columnName)

Returns the value of a non-NULL column with type Type.array(Type.timestamp()).

Parameter
Name Description
columnName String
Returns
Type Description
List<com.google.cloud.Timestamp>

getType()

public abstract Type getType()

Returns the type of the underlying data. This will always be a STRUCT type, with fields corresponding to the data's columns. For the result of a read or query, this will always match the columns passed to the read() call or named in the query text, in order.

Returns
Type Description
Type

getValue(int columnIndex)

public default Value getValue(int columnIndex)

Returns the value of a nullable column as a Value.

Parameter
Name Description
columnIndex int
Returns
Type Description
Value

getValue(String columnName)

public default Value getValue(String columnName)

Returns the value of a nullable column as a Value.

Parameter
Name Description
columnName String
Returns
Type Description
Value

isNull(int columnIndex)

public abstract boolean isNull(int columnIndex)

Returns true if a column contains a NULL value.

Parameter
Name Description
columnIndex int
Returns
Type Description
boolean

isNull(String columnName)

public abstract boolean isNull(String columnName)

Returns true if a column contains a NULL value.

Parameter
Name Description
columnName String
Returns
Type Description
boolean