Package org.mybatis.dynamic.sql.render

Class RenderingStrategy

java.lang.Object
org.mybatis.dynamic.sql.render.RenderingStrategy
Direct Known Subclasses:
MyBatis3RenderingStrategy, SpringNamedParameterRenderingStrategy
public abstract class RenderingStrategy extends Object
A rendering strategy is used to generate a platform specific binding.

Rendering strategies are used during the rendering phase of statement generation. All generated SQL statements include the generated statement itself, and a map of parameters that should be bound to the statement at execution time. For example, a generated select statement may look like this when rendered for MyBatis:

select foo from bar where id = #{parameters.p1,jdbcType=INTEGER}

In this case, the binding is #{parameters.p1,jdbcType=INTEGER}. MyBatis knows how to interpret this binding - it will look for a value in the parameters.p1 property of the parameter object passed to the statement and bind it as a prepared statement parameter when executing the statement.

  • Field Details

  • Constructor Details

    • RenderingStrategy

      public RenderingStrategy()

  • Method Details

    • formatParameterMapKey

      public String formatParameterMapKey(AtomicInteger sequence)
      Generate a unique key that can be used to place a parameter value in the parameter map.
      Parameters:
      sequence - a sequence for calculating a unique value
      Returns:
      a key used to place the parameter value in the parameter map

    • formatParameterMapKeyForFetchFirstRows

      public String formatParameterMapKeyForFetchFirstRows(AtomicInteger sequence)
      Return a parameter map key intended as a parameter for a fetch first query.

      By default, this parameter is treated the same as any other. This method is a hook to support MyBatis Spring Batch.

      Parameters:
      sequence - a sequence for calculating a unique value
      Returns:
      a key used to place the parameter value in the parameter map

    • formatParameterMapKeyForLimit

      public String formatParameterMapKeyForLimit(AtomicInteger sequence)
      Return a parameter map key intended as a parameter for a limit query.

      By default, this parameter is treated the same as any other. This method is a hook to support MyBatis Spring Batch.

      Parameters:
      sequence - a sequence for calculating a unique value
      Returns:
      a key used to place the parameter value in the parameter map

    • formatParameterMapKeyForOffset

      public String formatParameterMapKeyForOffset(AtomicInteger sequence)
      Return a parameter map key intended as a parameter for a query offset.

      By default, this parameter is treated the same as any other. This method is a hook to support MyBatis Spring Batch.

      Parameters:
      sequence - a sequence for calculating a unique value
      Returns:
      a key used to place the parameter value in the parameter map

    • getFormattedJdbcPlaceholder

      public abstract String getFormattedJdbcPlaceholder(BindableColumn<?> column, String prefix, String parameterName)
      This method generates a binding for a parameter to a placeholder in a generated SQL statement.

      This binding is appropriate when there can be a mapping between a parameter and a known target column, In MyBatis, the binding can specify type information based on the column. The bindings are specific to the target framework.

      For MyBatis, a binding looks like this: "#{prefix.parameterName,jdbcType=xxx,typeHandler=xxx,javaType=xxx}"

      For Spring, a binding looks like this: ":parameterName"

      Parameters:
      column - column definition used for generating type details in a MyBatis binding. Ignored for Spring.
      prefix - parameter prefix used for locating the parameters in a SQL provider object. Typically, will be DEFAULT_PARAMETER_PREFIX. This is ignored for Spring.
      parameterName - name of the parameter. Typically generated by calling formatParameterMapKey(AtomicInteger)
      Returns:
      the generated binding

    • getFormattedJdbcPlaceholder

      public abstract String getFormattedJdbcPlaceholder(String prefix, String parameterName)
      This method generates a binding for a parameter to a placeholder in a generated SQL statement.

      This binding is appropriate when the parameter is bound to placeholder that is not a known column (such as a limit or offset parameter). The bindings are specific to the target framework.

      For MyBatis, a binding looks like this: "#{prefix.parameterName}"

      For Spring, a binding looks like this: ":parameterName"

      Parameters:
      prefix - parameter prefix used for locating the parameters in a SQL provider object. Typically, will be DEFAULT_PARAMETER_PREFIX. This is ignored for Spring.
      parameterName - name of the parameter. Typically generated by calling formatParameterMapKey(AtomicInteger)
      Returns:
      the generated binding

    • getFormattedJdbcPlaceholderForPagingParameters

      public String getFormattedJdbcPlaceholderForPagingParameters(String prefix, String parameterName)
      This method generates a binding for a parameter to a placeholder in a generated SQL statement.

      This method is used to generate bindings for limit, offset, and fetch first parameters. By default, these parameters are treated the same as any other. This method supports MyBatis Spring Batch integration where the parameter keys have predefined values and need special handling.

      Parameters:
      prefix - parameter prefix used for locating the parameters in a SQL provider object. Typically, will be DEFAULT_PARAMETER_PREFIX. This is ignored for Spring.
      parameterName - name of the parameter. Typically generated by calling formatParameterMapKey(AtomicInteger)
      Returns:
      the generated binding

    • getRecordBasedInsertBinding

      public String getRecordBasedInsertBinding(BindableColumn<?> column, String prefix, String parameterName)
      This method generates a binding for a parameter to a placeholder in a row based insert statement.

      This binding is specifically for use with insert, batch insert, and multirow insert statements. These statements bind parameters to properties of a row class. The Spring implementation changes the binding to match values expected for a these insert statements. For MyBatis, the binding is the same as getFormattedJdbcPlaceholder(BindableColumn, String, String).

      For MyBatis, a binding looks like this: "#{prefix.parameterName,jdbcType=xxx,typeHandler=xxx,javaType=xxx}"

      For Spring, a binding looks like this: ":prefix.parameterName"

      Parameters:
      column - column definition used for generating type details in a MyBatis binding. Ignored for Spring.
      prefix - parameter prefix used for locating the parameters in a SQL provider object. Typically, will be either "row" or "records[x]" to match the properties of the generated statement object class.
      parameterName - name of the parameter. Typically, this is a property in the row class associated with the insert statement.
      Returns:
      the generated binding

    • getRecordBasedInsertBinding

      public abstract String getRecordBasedInsertBinding(BindableColumn<?> column, String parameterName)
      This method generates a binding for a parameter to a placeholder in a row based insert statement.

      This binding is specifically for use with insert, batch insert, and multirow insert statements and the MapToRow mapping. These statements bind parameters to the row class directly.

      For MyBatis, a binding looks like this: "#{parameterName,jdbcType=xxx,typeHandler=xxx,javaType=xxx}"

      For Spring, a binding looks like this: ":parameterName"

      Parameters:
      column - column definition used for generating type details in a MyBatis binding. Ignored for Spring.
      parameterName - name of the parameter. Typically, will be either "row" or "records[x]" to match the properties of the generated statement object class.
      Returns:
      the generated binding