Interface VariableScope

  • All Superinterfaces:
    org.flowable.common.engine.api.variable.VariableContainer

    public interface VariableScope
    extends org.flowable.common.engine.api.variable.VariableContainer
    Interface for class that acts as a scope for variables: i.e. the implementation can be used to set and get variables. Variables are typically stored on the 'highest parent'. For executions, this means that when called on an execution the variable will be stored on the process instance execution. Variables can be stored on the actual scope itself though, by calling the xxLocal methods.
    Author:
    Tom Baeyens, Joram Barrez
    • Method Detail

      • empty

        static VariableScope empty()
        Returns:
        an empty (null object) variable scope.
      • getVariables

        Map<String,​Object> getVariables()
        Returns all variables. This will include all variables of parent scopes too.
      • getVariableInstances

        Map<String,​VariableInstance> getVariableInstances()
        Returns all variables, as instances of the VariableInstance interface, which gives more information than only the value (type, execution id, etc.)
      • getVariables

        Map<String,​Object> getVariables​(Collection<String> variableNames,
                                              boolean fetchAllVariables)
        Similar to getVariables(Collection), but with a flag that indicates that all variables should be fetched when fetching the specific variables. If set to false, only the specific variables will be fetched. Depending on the use case, this can be better for performance, as it avoids fetching and processing the other variables. However, if the other variables are needed further on, getting them in one go is probably better (and the variables are cached during one Command execution).
      • getVariablesLocal

        Map<String,​Object> getVariablesLocal()
        Returns the variable local to this scope only. So, in contrary to getVariables(), the variables from the parent scope won't be returned.
      • getVariableInstancesLocal

        Map<String,​VariableInstance> getVariableInstancesLocal()
        Returns the variables local to this scope as instances of the VariableInstance interface, which provided additional information about the variable.
      • getVariable

        Object getVariable​(String variableName)
        Returns the variable value for one specific variable. Will look in parent scopes when the variable does not exist on this particular scope.
        Specified by:
        getVariable in interface org.flowable.common.engine.api.variable.VariableContainer
      • getVariable

        Object getVariable​(String variableName,
                           boolean fetchAllVariables)
        Similar to getVariable(String), but has an extra flag that indicates whether or not all variables need to be fetched when getting one variable. By default true (for backwards compatibility reasons), which means that calling getVariable(String) will fetch all variables, of the current scope and all parent scopes. Setting this flag to false can thus be better for performance. However, variables are cached, and if other variables are used later on, setting this true might actually be better for performance.
      • getVariableLocal

        Object getVariableLocal​(String variableName)
        Returns the value for the specific variable and only checks this scope and not any parent scope.
      • getVariableLocal

        Object getVariableLocal​(String variableName,
                                boolean fetchAllVariables)
        Similar to getVariableLocal(String), but has an extra flag that indicates whether or not all variables need to be fetched when getting one variable. By default true (for backwards compatibility reasons), which means that calling getVariableLocal(String) will fetch all variables, of the current scope. Setting this flag to false can thus be better for performance. However, variables are cached, and if other variables are used later on, setting this true might actually be better for performance.
      • getVariableNames

        Set<String> getVariableNames()
        Returns all the names of the variables for this scope and all parent scopes.
      • getVariableNamesLocal

        Set<String> getVariableNamesLocal()
        Returns all the names of the variables for this scope (no parent scopes).
      • setVariable

        void setVariable​(String variableName,
                         Object value)
        Sets the variable with the provided name to the provided value. In the case when variable name is an expression which is resolved by expression manager, the value is set in the object resolved from the expression.

        A variable is set according to the following algorithm:

        • If variable name is an expression, resolve expression and set the value on the resolved object.
        • If this scope already contains a variable by the provided name as a local variable, its value is overwritten to the provided value.
        • If this scope does not contain a variable by the provided name as a local variable, the variable is set to this scope's parent scope, if there is one. If there is no parent scope (meaning this scope is the root scope of the hierarchy it belongs to), this scope is used. This applies recursively up the parent scope chain until, if no scope contains a local variable by the provided name, ultimately the root scope is reached and the variable value is set on that scope.
        In practice for most cases, this algorithm will set variables to the scope of the execution at the process instance’s root level, if there is no execution-local variable by the provided name.
        Specified by:
        setVariable in interface org.flowable.common.engine.api.variable.VariableContainer
        Parameters:
        variableName - the name of the variable to be set
        value - the value of the variable to be set
      • setVariable

        void setVariable​(String variableName,
                         Object value,
                         boolean fetchAllVariables)
        Similar to setVariable(String, Object), but with an extra flag to indicate whether all variables should be fetched while doing this or not. Variable name expression is not resolved. The variable will be put on the highest possible scope. For an execution this is the process instance execution. If this is not wanted, use the setVariableLocal(String, Object) method instead. The default (e.g. when calling setVariable(String, Object)), is true, for backwards compatibility reasons. However, in some use cases, it might make sense not to fetch any other variables when setting one variable (for example when doing nothing more than just setting one variable).
      • setVariableLocal

        Object setVariableLocal​(String variableName,
                                Object value)
        Similar to setVariable(String, Object), but the variable is set to this scope specifically. Variable name is handled as a variable name string without resolving an expression.
      • setVariableLocal

        Object setVariableLocal​(String variableName,
                                Object value,
                                boolean fetchAllVariables)
        Similar to setVariableLocal(String, Object), but with an extra flag to indicate whether all variables should be fetched while doing this or not.
      • setVariables

        void setVariables​(Map<String,​? extends Object> variables)
        Sets the provided variables to the variable scope.

        Variables are set according algorithm for setVariable(String, Object), applied separately to each variable.

        Parameters:
        variables - a map of keys and values for the variables to be set
      • setVariablesLocal

        void setVariablesLocal​(Map<String,​? extends Object> variables)
        Similar to setVariables(Map), but the variable are set on this scope specifically.
      • hasVariables

        boolean hasVariables()
        Returns whether this scope or any parent scope has variables.
      • hasVariablesLocal

        boolean hasVariablesLocal()
        Returns whether this scope has variables.
      • hasVariable

        boolean hasVariable​(String variableName)
        Returns whether this scope or any parent scope has a specific variable.
        Specified by:
        hasVariable in interface org.flowable.common.engine.api.variable.VariableContainer
      • hasVariableLocal

        boolean hasVariableLocal​(String variableName)
        Returns whether this scope has a specific variable.
      • removeVariable

        void removeVariable​(String variableName)
        Removes the variable and creates a new HistoricVariableUpdate.
      • removeVariableLocal

        void removeVariableLocal​(String variableName)
        Removes the local variable and creates a new HistoricVariableUpdate.
      • removeVariables

        void removeVariables​(Collection<String> variableNames)
        Removes the variables and creates a new HistoricVariableUpdate for each of them.
      • removeVariablesLocal

        void removeVariablesLocal​(Collection<String> variableNames)
        Removes the local variables and creates a new HistoricVariableUpdate for each of them.
      • removeVariables

        void removeVariables()
        Removes the (local) variables and creates a new HistoricVariableUpdate for each of them.
      • removeVariablesLocal

        void removeVariablesLocal()
        Removes the (local) variables and creates a new HistoricVariableUpdate for each of them.
      • setTransientVariable

        void setTransientVariable​(String variableName,
                                  Object variableValue)
        Similar to setVariable(String, Object), but the variable is transient: - no history is kept for the variable - the variable is only available until a waitstate is reached in the process - transient variables 'shadow' persistent variable (when getVariable('abc') where 'abc' is both persistent and transient, the transient value is returned.
        Specified by:
        setTransientVariable in interface org.flowable.common.engine.api.variable.VariableContainer
      • removeTransientVariableLocal

        void removeTransientVariableLocal​(String variableName)
        Removes a specific transient variable (also searching parent scopes). See setTransientVariable(String, Object) for the rules on 'transient' variables.
      • removeTransientVariables

        void removeTransientVariables()
        Remove all transient variable of this scope and its parent scopes. See setTransientVariable(String, Object) for the rules on 'transient' variables.
      • removeTransientVariablesLocal

        void removeTransientVariablesLocal()
        Removes all local transient variables. See setTransientVariable(String, Object) for the rules on 'transient' variables.