private String getProperty(String propertyName) {
        return getProperty(propertyName, null, true);
    }

    private String getProperty(String propertyName, String defaultValue) {
        return getProperty(propertyName, defaultValue, true);
    }

    private int getProperty(String propertyName, int defaultValue) {
        return Integer.parseInt(getProperty(propertyName, String.valueOf(defaultValue)));
    }

        if (value != null) {
            System.setProperty(propertyName, value);
        } else {
            System.clearProperty(propertyName);
        }
        return originalValue;
    }

    private void restoreProperty(String propertyName, @Nullable String originalValue) {
        if (originalValue != null) {
            System.setProperty(propertyName, originalValue);
        } else {

            visitor.visitInputProperty(propertyName, value, optional);
        }
    }

    @Override
    public void visitOutputFileProperty(String propertyName, boolean optional, PropertyValue value, OutputFilePropertyType filePropertyType) {
        for (PropertyVisitor visitor : visitors) {
            visitor.visitOutputFileProperty(propertyName, optional, value, filePropertyType);
        }
    }

    private final Class<?> targetClass;

    private final String propertyName;

    /**
     * {@link PropertyNotFoundRuntimeException}を返します。
     *
     * @param targetClass
     *            ターゲットクラス
     * @param propertyName
     *            プロパティ名
     */
    public PropertyNotFoundRuntimeException(final Class<?> targetClass, final String propertyName) {
        super("ECL0065", asArray(targetClass.getName(), propertyName));

    }

    @Override
    Provider<String> systemProperty(String propertyName) {
        return Providers.ofNullable(System.getProperty(propertyName))
    }

    @Override
    Provider<String> systemProperty(Provider<String> propertyName) {
        return systemProperty(propertyName.get());
    }

    @Override
    Provider<String> gradleProperty(String propertyName) {
        return Providers.notDefined()
    }

    @Override

    private final String propertyName;
    private final StaticValue value;
    private boolean optional;

    public DefaultTaskInputPropertyRegistration(String propertyName, StaticValue value) {
        this.propertyName = propertyName;
        this.value = value;
    }

    @Override
    public String getPropertyName() {
        return propertyName;
    }

    @Override

        return new DefaultInputFileChanges(
            Maps.filterKeys(previous, propertyName -> !incrementalInputProperties.containsKey(propertyName)),
            Maps.filterKeys(current, propertyName -> !incrementalInputProperties.containsKey(propertyName))
        );

    }

    @Override

        return __modifiedProperties.getPropertyNames();
    }

    public void mymodifyProperty(String propertyName) {
        registerModifiedProperty(propertyName);
    }

    public void mymodifyPropertyCancel(String propertyName) {
        __modifiedProperties.remove(propertyName);
    }

    public void clearModifiedInfo() {
        __modifiedProperties.clear();
    }

                    consumer1.visitEmptyOutputFileProperty(propertyName, optional, value);
                    consumer2.visitEmptyOutputFileProperty(propertyName, optional, value);
                }
            };
        }
    }

    @Override

        }

        @Override
        public TypeValidationDataSpec pluginId(String pluginId) {
            this.pluginId = pluginId;
            return this;
        }

        @Override
        public TypeValidationDataSpec propertyName(String propertyName) {
            this.propertyName = propertyName;
            return this;
        }