Move SpecProperties from drools-pdp to common

Change-Id: Ifa1785922b42f990d4d84c1410dd1d881b10647d
Issue-ID: POLICY-907
Signed-off-by: Jim Hahn <jrh3@att.com>

2 files changed, 341 insertions, 0 deletions

diff --git a/utils/src/main/java/org/onap/policy/common/utils/properties/SpecProperties.java b/utils/src/main/java/org/onap/policy/common/utils/properties/SpecProperties.java
new file mode 100644
index 00000000..0f416c3a
--- /dev/null
+++ b/utils/src/main/java/org/onap/policy/common/utils/properties/SpecProperties.java
@@ -0,0 +1,117 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.properties;
+
+import java.util.Properties;
+
+/**
+ * Properties with an optional specialization (e.g., session name, controller name).
+ */
+public class SpecProperties extends Properties {
+    private static final long serialVersionUID = 1L;
+
+    /**
+     * The property prefix, ending with ".".
+     */
+    private final String prefix;
+
+    /**
+     * The specialized property prefix, ending with ".".
+     */
+    private final String specPrefix;
+
+    /**
+     * 
+     * @param prefix the property name prefix that appears before any specialization, may
+     *        be ""
+     * @param specialization the property name specialization (e.g., session name)
+     */
+    public SpecProperties(String prefix, String specialization) {
+        this.prefix = withTrailingDot(prefix);
+        this.specPrefix = withTrailingDot(this.prefix + specialization);
+    }
+
+    /**
+     * 
+     * @param prefix the property name prefix that appears before any specialization, may
+     *        be ""
+     * @param specialization the property name specialization (e.g., session name)
+     * @param props the default properties
+     */
+    public SpecProperties(String prefix, String specialization, Properties props) {
+        super(props);
+
+        this.prefix = withTrailingDot(prefix);
+        this.specPrefix = withTrailingDot(this.prefix + specialization);
+    }
+
+    /**
+     * Adds a trailing "." to a String, if it doesn't already have one.
+     * 
+     * @param text text to which the "." should be added
+     * @return the text, with a trailing "."
+     */
+    private static String withTrailingDot(String text) {
+        return text.isEmpty() || text.endsWith(".") ? text : text + ".";
+    }
+
+    /**
+     * Gets the property whose value has the given key, looking first for the specialized
+     * property name, and then for the generalized property name.
+     * 
+     * @param key property name, without the specialization
+     * @return the value from the property set, or {@code null} if the property set does
+     *         not contain the value
+     */
+    @Override
+    public String getProperty(String key) {
+        if (!key.startsWith(prefix)) {
+            return super.getProperty(key);
+        }
+
+        String suffix = key.substring(prefix.length());
+
+        String val = super.getProperty(specPrefix + suffix);
+        if (val != null) {
+            return val;
+        }
+
+        return super.getProperty(key);
+    }
+
+    protected String getPrefix() {
+        return prefix;
+    }
+
+    protected String getSpecPrefix() {
+        return specPrefix;
+    }
+
+    @Override
+    public final int hashCode() {
+        throw new UnsupportedOperationException("SpecProperties cannot be hashed");
+    }
+
+    @Override
+    public final boolean equals(Object obj) {
+        throw new UnsupportedOperationException("cannot compare SpecProperties");
+    }
+}
diff --git a/utils/src/test/java/org/onap/policy/common/utils/properties/SpecPropertiesTest.java b/utils/src/test/java/org/onap/policy/common/utils/properties/SpecPropertiesTest.java
new file mode 100644
index 00000000..01f096d1
--- /dev/null
+++ b/utils/src/test/java/org/onap/policy/common/utils/properties/SpecPropertiesTest.java
@@ -0,0 +1,224 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.properties;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import java.util.Properties;
+import org.junit.Before;
+import org.junit.Test;
+
+public class SpecPropertiesTest {
+
+    /**
+     * Property prefix of interest.
+     */
+    private static final String MY_PREFIX = "my.prefix";
+
+    /**
+     * Specialization, which follows the prefix.
+     */
+    private static final String MY_SPEC = "my.spec";
+
+    /**
+     * Generalized prefix (i.e., without the spec).
+     */
+    private static final String PREFIX_GEN = MY_PREFIX + ".";
+
+    /**
+     * Specialized prefix (i.e., with the spec).
+     */
+    private static final String PREFIX_SPEC = PREFIX_GEN + MY_SPEC + ".";
+
+    /**
+     * Suffix to add to property names to generate names of properties that are not
+     * populated.
+     */
+    private static final String SUFFIX = ".suffix";
+
+    /**
+     * Property name without a prefix.
+     */
+    private static final String PROP_NO_PREFIX = "other";
+
+    /**
+     * Generalized property name (i.e., without the spec).
+     */
+    private static final String PROP_GEN = PREFIX_GEN + "generalized";
+
+    // property names that include the spec
+    private static final String PROP_SPEC = PREFIX_SPEC + "specialized";
+    private static final String PROP_UNKNOWN = PREFIX_SPEC + "unknown";
+
+    // property values
+    private static final String VAL_NO_PREFIX = "no-prefix";
+    private static final String VAL_GEN = "gen";
+    private static final String VAL_SPEC = "spec";
+
+    private static final String VAL_DEFAULT = "default value";
+
+    private Properties supportingProps;
+    private SpecProperties props;
+
+    @Before
+    public void setUp() {
+        supportingProps = new Properties();
+
+        supportingProps.setProperty(PROP_NO_PREFIX, VAL_NO_PREFIX);
+        supportingProps.setProperty(PROP_GEN, VAL_GEN);
+        supportingProps.setProperty(PROP_SPEC, VAL_SPEC);
+
+        props = new SpecProperties(MY_PREFIX, MY_SPEC);
+
+        props.putAll(supportingProps);
+    }
+
+    @Test
+    public void testSpecPropertiesStringString() {
+
+        // no supporting properties
+        props = new SpecProperties(MY_PREFIX, MY_SPEC);
+
+        assertEquals(PREFIX_GEN, props.getPrefix());
+        assertEquals(PREFIX_SPEC, props.getSpecPrefix());
+
+        // everything is null
+        assertNull(props.getProperty(gen(PROP_NO_PREFIX)));
+        assertNull(props.getProperty(gen(PROP_GEN)));
+        assertNull(props.getProperty(gen(PROP_SPEC)));
+        assertNull(props.getProperty(gen(PROP_UNKNOWN)));
+    }
+
+    @Test
+    public void testSpecPropertiesStringStringProperties() {
+
+        // use supportingProps as default properties
+        props = new SpecProperties(MY_PREFIX, MY_SPEC, supportingProps);
+
+        assertEquals(PREFIX_GEN, props.getPrefix());
+        assertEquals(PREFIX_SPEC, props.getSpecPrefix());
+
+        assertEquals(VAL_NO_PREFIX, props.getProperty(gen(PROP_NO_PREFIX)));
+        assertEquals(VAL_GEN, props.getProperty(gen(PROP_GEN)));
+        assertEquals(VAL_SPEC, props.getProperty(gen(PROP_SPEC)));
+        assertNull(props.getProperty(gen(PROP_UNKNOWN)));
+    }
+
+    @Test
+    public void testSpecPropertiesStringStringProperties_EmptyPrefix() {
+        supportingProps = new Properties();
+
+        supportingProps.setProperty(PROP_NO_PREFIX, VAL_NO_PREFIX);
+        supportingProps.setProperty("a.value", VAL_GEN);
+        supportingProps.setProperty("b.value", VAL_GEN);
+        supportingProps.setProperty(MY_SPEC + ".b.value", VAL_SPEC);
+
+        // no supporting properties
+        props = new SpecProperties("", MY_SPEC, supportingProps);
+
+        assertEquals(VAL_NO_PREFIX, props.getProperty(gen(PROP_NO_PREFIX)));
+        assertEquals(VAL_GEN, props.getProperty(gen("a.value")));
+        assertEquals(VAL_SPEC, props.getProperty(MY_SPEC + ".b.value"));
+        assertNull(props.getProperty(gen(PROP_UNKNOWN)));
+    }
+
+    @Test
+    public void testWithTrailingDot() {
+        // neither has trailing dot
+        assertEquals(PREFIX_GEN, props.getPrefix());
+        assertEquals(PREFIX_SPEC, props.getSpecPrefix());
+
+        // both have trailing dot
+        props = new SpecProperties(PREFIX_GEN, MY_SPEC + ".");
+        assertEquals(PREFIX_GEN, props.getPrefix());
+        assertEquals(PREFIX_SPEC, props.getSpecPrefix());
+
+        // first is empty
+        props = new SpecProperties("", MY_SPEC);
+        assertEquals("", props.getPrefix());
+        assertEquals(MY_SPEC + ".", props.getSpecPrefix());
+
+        // second is empty
+        props = new SpecProperties(PREFIX_GEN, "");
+        assertEquals(PREFIX_GEN, props.getPrefix());
+        assertEquals(PREFIX_GEN, props.getSpecPrefix());
+    }
+
+    @Test
+    public void testGetPropertyString() {
+        // the key does contain the prefix
+        assertEquals(VAL_NO_PREFIX, props.getProperty(gen(PROP_NO_PREFIX)));
+        assertNull(props.getProperty(gen(PROP_NO_PREFIX + SUFFIX)));
+
+        // specialized value exists
+        assertEquals(VAL_GEN, props.getProperty(gen(PROP_GEN)));
+        assertNull(props.getProperty(gen(PROP_GEN + SUFFIX)));
+
+        // generalized value exists
+        assertEquals(VAL_SPEC, props.getProperty(gen(PROP_SPEC)));
+        assertNull(props.getProperty(gen(PROP_SPEC + SUFFIX)));
+
+        // not found
+        assertNull(props.getProperty(gen(PROP_UNKNOWN)));
+        assertNull(props.getProperty(gen(PROP_UNKNOWN + SUFFIX)));
+    }
+
+    @Test
+    public void testGetPropertyStringString() {
+        // the key does contain the prefix
+        assertEquals(VAL_NO_PREFIX, props.getProperty(gen(PROP_NO_PREFIX), VAL_DEFAULT));
+        assertEquals(VAL_DEFAULT, props.getProperty(gen(PROP_NO_PREFIX + SUFFIX), VAL_DEFAULT));
+
+        // specialized value exists
+        assertEquals(VAL_GEN, props.getProperty(gen(PROP_GEN), VAL_DEFAULT));
+        assertEquals(VAL_DEFAULT, props.getProperty(gen(PROP_GEN + SUFFIX), VAL_DEFAULT));
+
+        // generalized value exists
+        assertEquals(VAL_SPEC, props.getProperty(gen(PROP_SPEC), VAL_DEFAULT));
+        assertEquals(VAL_DEFAULT, props.getProperty(gen(PROP_SPEC + SUFFIX), VAL_DEFAULT));
+
+        // not found
+        assertEquals(VAL_DEFAULT, props.getProperty(gen(PROP_UNKNOWN), VAL_DEFAULT));
+        assertEquals(VAL_DEFAULT, props.getProperty(gen(PROP_UNKNOWN + SUFFIX), VAL_DEFAULT));
+
+        // can return null
+        assertNull(props.getProperty(gen(PROP_UNKNOWN), null));
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testHashCode() {
+        props.hashCode();
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testEquals() {
+        props.equals(props);
+    }
+
+    private String gen(String propnm) {
+        if (propnm.startsWith(PREFIX_SPEC)) {
+            return PREFIX_GEN + propnm.substring(PREFIX_SPEC.length());
+        }
+
+        return propnm;
+    }
+
+}