org.activiti.engine.delegate.VariableScope Maven / Gradle / Ivy
/* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.activiti.engine.delegate;
import java.util.Collection;
import java.util.Map;
import java.util.Set;
import org.activiti.engine.history.HistoricVariableUpdate;
import org.activiti.engine.impl.interceptor.Command;
import org.activiti.engine.impl.persistence.entity.VariableInstance;
/**
* Interface for class that acts as a scope for variables: i.e. the implementation
* can be used to set and get variables.
*
* Typically, executions (and thus process instances) and tasks are the primary use case
* to get and set variables. The {@link DelegateExecution} for example is often used
* in {@link JavaDelegate} implementation to get and set 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.
*
*/
public interface VariableScope {
/**
* Returns all variables.
* This will include all variables of parent scopes too.
*/
Map getVariables();
/**
* Returns all variables, as instances of the {@link VariableInstance} interface,
* which gives more information than only the the value (type, execution id, etc.)
*/
Map getVariableInstances();
/**
* Similar to {@link #getVariables()}, but limited to only the variables with the provided names.
*/
Map getVariables(Collection variableNames);
/**
* Similar to {@link #getVariableInstances()}, but limited to only the variables with the provided names.
*/
Map getVariableInstances(Collection variableNames);
/**
* Similar to {@link #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.
* Dependening 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 {@link Command} execution).
*/
Map getVariables(Collection variableNames, boolean fetchAllVariables);
/**
* Similar to {@link #getVariables(Collection, boolean)} but returns the variables
* as instances of the {@link VariableInstance} interface,
* which gives more information than only the the value (type, execution id, etc.)
*/
Map getVariableInstances(Collection variableNames, boolean fetchAllVariables);
/**
* Returns the variable local to this scope only.
* So, in contrary to {@link #getVariables()}, the variables from the parent scope won't be returned.
*/
Map getVariablesLocal();
/**
* Returns the variables local to this scope as instances of the {@link VariableInstance} interface,
* which provided additional information about the variable.
*/
Map getVariableInstancesLocal();
/**
* Similar to {@link #getVariables(Collection)}, but only for variables local to this scope.
*/
Map getVariablesLocal(Collection variableNames);
/**
* Similar to {@link #getVariableInstances(Collection)}, but only for variables local to this scope.
*/
Map getVariableInstancesLocal(Collection variableNames);
/**
* Similar to {@link #getVariables(Collection, boolean)}, but only for variables local to this scope.
*/
Map getVariablesLocal(Collection variableNames, boolean fetchAllVariables);
/**
* Similar to {@link #getVariableInstances(Collection, boolean)}, but only for variables local to this scope.
*/
Map getVariableInstancesLocal(Collection variableNames, boolean fetchAllVariables);
/**
* Returns the variable value for one specific variable.
* Will look in parent scopes when the variable does not exist on this particular scope.
*/
Object getVariable(String variableName);
/**
* Similar to {@link #getVariable(String)}, but returns a {@link VariableInstance} instance,
* which contains more information than just the value.
*/
VariableInstance getVariableInstance(String variableName);
/**
* Similar to {@link #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 {@link #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.
*/
Object getVariable(String variableName, boolean fetchAllVariables);
/**
* Similar to {@link #getVariable(String, boolean)}, but returns an instance of {@link VariableInstance},
* which has some additional information beyond the value.
*/
VariableInstance getVariableInstance(String variableName, boolean fetchAllVariables);
/**
* Returns the value for the specific variable and only checks this scope and not any parent scope.
*/
Object getVariableLocal(String variableName);
/**
* Similar to {@link #getVariableLocal(String)}, but returns an instance of {@link VariableInstance},
* which has some additional information beyond the value.
*/
VariableInstance getVariableInstanceLocal(String variableName);
/**
* Similar to {@link #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 {@link #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.
*/
Object getVariableLocal(String variableName, boolean fetchAllVariables);
/**
* Similar to {@link #getVariableLocal(String, boolean)}, but returns an instance of {@link VariableInstance},
* which has some additional information beyond the value.
*/
VariableInstance getVariableInstanceLocal(String variableName, boolean fetchAllVariables);
/**
* Typed version of the {@link #getVariable(String)} method.
*/
T getVariable(String variableName, Class variableClass);
/**
* Typed version of the {@link #getVariableLocal(String)} method.
*/
T getVariableLocal(String variableName, Class variableClass);
/**
* Returns all the names of the variables for this scope and all parent scopes.
*/
Set getVariableNames();
/**
* Returns all the names of the variables for this scope (no parent scopes).
*/
Set getVariableNamesLocal();
/**
* Sets the variable with the provided name to the provided value.
*
*
* A variable is set according to the following algorithm:
*
*
*
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.
*
* @param variableName
* the name of the variable to be set
* @param value
* the value of the variable to be set
*/
void setVariable(String variableName, Object value);
/**
* Similar to {@link #setVariable(String, Object)}, but with an extra flag to indicate whether
* all variables should be fetched while doing this or not.
*
* 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 {@link #setVariableLocal(String, Object)} method instead.
*
* The default (e.g. when calling {@link #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).
*/
void setVariable(String variableName, Object value, boolean fetchAllVariables);
/**
* Similar to {@link #setVariable(String, Object)}, but the variable is set to this scope specifically.
*/
Object setVariableLocal(String variableName, Object value);
/**
* Similar to {@link #setVariableLocal(String, Object, boolean)}, but the variable is set to this scope specifically.
*/
Object setVariableLocal(String variableName, Object value, boolean fetchAllVariables);
/**
* Sets the provided variables to the variable scope.
*
*
* Variables are set according algorithm for {@link #setVariable(String, Object)}, applied separately to each variable.
*
* @param variables
* a map of keys and values for the variables to be set
*/
void setVariables(Map variables);
/**
* Similar to {@link #setVariables(Map)}, but the variable are set on this scope specifically.
*/
void setVariablesLocal(Map variables);
/**
* Returns whether this scope or any parent scope has variables.
*/
boolean hasVariables();
/**
* Returns whether this scope has variables.
*/
boolean hasVariablesLocal();
/**
* Returns whether this scope or any parent scope has a specific variable.
*/
boolean hasVariable(String variableName);
/**
* Returns whether this scope has a specific variable.
*/
boolean hasVariableLocal(String variableName);
/**
* Removes the variable and creates a new;@link HistoricVariableUpdateEntity}
*/
void removeVariable(String variableName);
/**
* Removes the local variable and creates a new {@link HistoricVariableUpdate}.
*/
void removeVariableLocal(String variableName);
/**
* Removes the variables and creates a new
* {@link HistoricVariableUpdate} for each of them.
*/
void removeVariables(Collection variableNames);
/**
* Removes the local variables and creates a new
* {@link HistoricVariableUpdate} for each of them.
*/
void removeVariablesLocal(Collection variableNames);
/**
* Removes the (local) variables and creates a new
* {@link HistoricVariableUpdate} for each of them.
*/
void removeVariables();
/**
* Removes the (local) variables and creates a new
* {@link HistoricVariableUpdate} for each of them.
*/
void removeVariablesLocal();
/**
* Similar to {@link #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.
*/
void setTransientVariable(String variableName, Object variableValue);
/**
* Similar to {@link #setVariableLocal(String, Object)}, but for a transient variable.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void setTransientVariableLocal(String variableName, Object variableValue);
/**
* Similar to {@link #setVariables(Map)}, but for transient variables.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void setTransientVariables(Map transientVariables);
/**
* Similar to {@link #getVariable(String)}, including the searching via the parent scopes, but
* for transient variables only.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
Object getTransientVariable(String variableName);
/**
* Similar to {@link #getVariables()}, but for transient variables only.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
Map getTransientVariables();
/**
* Similar to {@link #setVariablesLocal(Map)}, but for transient variables.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void setTransientVariablesLocal(Map transientVariables);
/**
* Similar to {@link #getVariableLocal(String)}, but for a transient variable.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
Object getTransientVariableLocal(String variableName);
/**
* Similar to {@link #getVariableLocal(String)}, but for transient variables only.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
Map getTransientVariablesLocal();
/**
* Removes a specific transient variable (also searching parent scopes).
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void removeTransientVariableLocal(String variableName);
/**
* Removes a specific transient variable.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void removeTransientVariable(String variableName);
/**
* Remove all transient variable of this scope and its parent scopes.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void removeTransientVariables();
/**
* Removes all local transient variables.
* See {@link #setTransientVariable(String, Object)} for the rules on 'transient' variables.
*/
void removeTransientVariablesLocal();
}