org.apache.flink.ml.common.utils

类 OutputColsHelper

java.lang.Object

org.apache.flink.ml.common.utils.OutputColsHelper

所有已实现的接口:

Serializable

public class OutputColsHelper
extends Object
implements Serializable

Utils for merging input data with output data.

Input: 1) Schema of input data being predicted or transformed. 2) Output column names of the prediction/transformation operator. 3) Output column types of the prediction/transformation operator. 4) Reserved column names, which is a subset of input data's column names that we want to preserve.

Output: 1）The result data schema. The result data is a combination of the preserved columns and the operator's output columns.

Several rules are followed:

• If reserved columns are not given, then all columns of input data is reserved.
• The reserved columns are arranged ahead of the operator's output columns in the final output.
• If some of the reserved column names overlap with those of operator's output columns, then the operator's output columns override the conflicting reserved columns.
• The reserved columns in the result table preserve their orders as in the input table.

For example, if we have input data schema of ["id":INT, "f1":FLOAT, "f2":DOUBLE], and the operator outputs a column "label" with type STRING, and we want to preserve the column "id", then we get the result schema of ["id":INT, "label":STRING].

end user should not directly interact with this helper class. instead it will be indirectly used via concrete algorithms.

另请参阅:

序列化表格

构造器概要

构造器

构造器和说明
OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema, String[] outputColNames, org.apache.flink.api.common.typeinfo.TypeInformation<?>[] outputColTypes)
OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema, String[] outputColNames, org.apache.flink.api.common.typeinfo.TypeInformation<?>[] outputColTypes, String[] reservedColNames) The constructor.
OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema, String outputColName, org.apache.flink.api.common.typeinfo.TypeInformation<?> outputColType)
OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema, String outputColName, org.apache.flink.api.common.typeinfo.TypeInformation<?> outputColType, String[] reservedColNames)

方法概要

限定符和类型	方法和说明
String[]	getReservedColumns() Get the reserved columns' names.
org.apache.flink.types.Row	getResultRow(org.apache.flink.types.Row input, org.apache.flink.types.Row output) Merge the input row and the output row.
org.apache.flink.table.api.TableSchema	getResultSchema() Get the result table schema.

从类继承的方法 java.lang.Object

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

构造器详细资料

OutputColsHelper

public OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema,
                        String outputColName,
                        org.apache.flink.api.common.typeinfo.TypeInformation<?> outputColType)

OutputColsHelper

public OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema,
                        String outputColName,
                        org.apache.flink.api.common.typeinfo.TypeInformation<?> outputColType,
                        String[] reservedColNames)

OutputColsHelper

public OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema,
                        String[] outputColNames,
                        org.apache.flink.api.common.typeinfo.TypeInformation<?>[] outputColTypes)

OutputColsHelper

public OutputColsHelper(org.apache.flink.table.api.TableSchema inputSchema,
                        String[] outputColNames,
                        org.apache.flink.api.common.typeinfo.TypeInformation<?>[] outputColTypes,
                        String[] reservedColNames)

The constructor.

参数:

inputSchema - Schema of input data being predicted or transformed.

outputColNames - Output column names of the prediction/transformation operator.

outputColTypes - Output column types of the prediction/transformation operator.

reservedColNames - Reserved column names, which is a subset of input data's column names that we want to preserve.

方法详细资料

getReservedColumns

public String[] getReservedColumns()

Get the reserved columns' names.

返回:

the reserved colNames.

getResultSchema

public org.apache.flink.table.api.TableSchema getResultSchema()

Get the result table schema. The result data is a combination of the preserved columns and the operator's output columns.

返回:

The result table schema.

getResultRow

public org.apache.flink.types.Row getResultRow(org.apache.flink.types.Row input,
                                               org.apache.flink.types.Row output)

Merge the input row and the output row.

参数:

input - The input row being predicted or transformed.

output - The output row of the prediction/transformation operator.

返回:

The result row, which is a combination of preserved columns and the operator's output columns.