In 'VariableWrapper.java' file, the method 'asBoolean()' which actually calls 'getBooleanValue()' is implemented.
However, 'Variable.java' file has no 'asBoolean()', 'getBooleanValue()'.
For this reason, there is different behavior between 'build.getVar' and 'configuration.getVar' when check variable as boolean value.
Please consider to add 'asBoolean()', 'getBooleanValue()' even in 'Variable.java' like 'VariableWrapper.java'.
Description
In 'VariableWrapper.java' file, the method 'asBoolean()' which actually calls 'getBooleanValue()' is implemented.
However, 'Variable.java' file has no 'asBoolean()', 'getBooleanValue()'.
For this reason, there is different behavior between 'build.getVar' and 'configuration.getVar' when check variable as boolean value.
Please consider to add 'asBoolean()', 'getBooleanValue()' even in 'Variable.java' like 'VariableWrapper.java'.