Use setXxx() methods for @Property fields

Fortify generates a security exception when PropertyConfiguration
attempts to directly update private fields.  PropertyConfiguration
has been modified to invoke setXxx() methods, instead, to set the
values for the fields.
Add junit tests for new methods.

Change-Id: Ic4420b6348724c5a384d3c2c8bf7b4c0c6350fa9
Issue-ID: POLICY-906
Signed-off-by: Jim Hahn <jrh3@att.com>

1 files changed, 47 insertions, 14 deletions

diff --git a/utils/src/main/java/org/onap/policy/common/utils/properties/PropertyConfiguration.java b/utils/src/main/java/org/onap/policy/common/utils/properties/PropertyConfiguration.java
index 7253c746..e72ebaba 100644
--- a/utils/src/main/java/org/onap/policy/common/utils/properties/PropertyConfiguration.java
+++ b/utils/src/main/java/org/onap/policy/common/utils/properties/PropertyConfiguration.java
@@ -25,8 +25,11 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.util.Properties;
+import org.apache.commons.lang3.StringUtils;
 import org.onap.policy.common.utils.properties.exception.PropertyAccessException;
 import org.onap.policy.common.utils.properties.exception.PropertyException;
 import org.onap.policy.common.utils.properties.exception.PropertyInvalidException;
@@ -35,7 +38,9 @@ import org.onap.policy.common.utils.properties.exception.PropertyMissingExceptio
 /**
  * Configuration whose fields are initialized by reading from a set of {@link Properties},
  * as directed by the {@link Property} annotations that appear on fields within the
- * subclass.
+ * subclass. The values of the fields are set via <i>setXxx()</i> methods. As a result, if
+ * a field is annotated and there is no corresponding <i>setXxx()</i> method, then an
+ * exception will be thrown.
  * <p>
  * It is possible that an invalid <i>defaultValue</i> is specified via the
  * {@link Property} annotation. This could remain undetected until an optional property is
@@ -104,7 +109,10 @@ public class PropertyConfiguration {
 
         checkModifiable(field, prop);
 
-        if (setValue(field, props, prop)) {
+        Method setter = getSetter(field, prop);
+        checkSetter(setter, prop);
+
+        if (setValue(setter, field, props, prop)) {
             return true;
         }
 
@@ -112,15 +120,33 @@ public class PropertyConfiguration {
     }
 
     /**
+     * @param field field whose value is to be set
+     * @param prop property of interest
+     * @return the method to be used to set the field's value
+     * @throws PropertyAccessException if a "set" method cannot be identified
+     */
+    private Method getSetter(Field field, Property prop) throws PropertyAccessException {
+        String nm = "set" + StringUtils.capitalize(field.getName());
+
+        try {
+            return this.getClass().getMethod(nm, field.getType());
+
+        } catch (NoSuchMethodException | SecurityException e) {
+            throw new PropertyAccessException(prop.name(), nm, e);
+        }
+    }
+
+    /**
      * Sets a field's value from a particular property.
      * 
+     * @param setter method to be used to set the field's value
      * @param field field whose value is to be set
      * @param props properties from which to get the value
      * @param prop property of interest
      * @return {@code true} if the property's value was set, {@code false} otherwise
      * @throws PropertyException if an error occurs
      */
-    protected boolean setValue(Field field, Properties props, Property prop) throws PropertyException {
+    protected boolean setValue(Method setter, Field field, Properties props, Property prop) throws PropertyException {
 
         try {
             Object val = getValue(field, props, prop);
@@ -128,23 +154,15 @@ public class PropertyConfiguration {
                 return false;
 
             } else {
-
-                /*
-                 * According to java docs & blogs, "field" is our own copy, so we're free
-                 * to change the flags without impacting the real permissions of the field
-                 * within the real class.
-                 */
-                field.setAccessible(true);
-
-                field.set(this, val);
+                setter.invoke(this, val);
                 return true;
             }
 
         } catch (IllegalArgumentException e) {
             throw new PropertyInvalidException(prop.name(), field.getName(), e);
 
-        } catch (IllegalAccessException e) {
-            throw new PropertyAccessException(prop.name(), field.getName(), e);
+        } catch (IllegalAccessException | InvocationTargetException e) {
+            throw new PropertyAccessException(prop.name(), setter.getName(), e);
         }
     }
 
@@ -203,6 +221,21 @@ public class PropertyConfiguration {
     }
 
     /**
+     * Verifies that the setter method is not <i>static</i>.
+     * 
+     * @param setter method to be checked
+     * @param prop property of interest
+     * @throws PropertyAccessException if the method is static
+     */
+    private void checkSetter(Method setter, Property prop) throws PropertyAccessException {
+        int mod = setter.getModifiers();
+
+        if (Modifier.isStatic(mod)) {
+            throw new PropertyAccessException(prop.name(), setter.getName(), "method is 'static'");
+        }
+    }
+
+    /**
      * Gets a property value, coercing it to a String.
      * 
      * @param fieldName field whose value is to be set