GP-1068 revised null state for primitive and fixed-length fields for

sparse records

Ghidra/Framework/DB/src/main/java/db/PrimitiveField.java

@@ -0,0 +1,74 @@
+/* ###
+ * IP: GHIDRA
+ *
+ * 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 db;
+
+/**
+ * <code>PrimitiveField</code> provides a base implementation for
+ * all primitive value {@link Field}s.  
+ * <br>
+ * When a {@link PrimitiveField} associated with a {@link SparseRecord} 
+ * has a null state it will have a zero (0) value. 
+ */
+abstract class PrimitiveField extends Field {
+
+	private boolean isNull = false;
+
+	/**
+	 * Abstract PrimitiveField Constructor for a mutable instance
+	 */
+	PrimitiveField() {
+		super();
+	}
+
+	/**
+	 * Abstract PrimitiveField Constructor
+	 * @param immutable true if field value is immutable
+	 */
+	PrimitiveField(boolean immutable) {
+		super(immutable);
+	}
+
+	@Override
+	final boolean isNull() {
+		return isNull;
+	}
+
+	@Override
+	void setNull() {
+		checkImmutable();
+		this.isNull = true;
+	}
+
+	/**
+	 * Invoked prior to setting the field's primitive value this
+	 * method will perform an immutable check and set to a non-null 
+	 * state.
+	 */
+	final void updatingPrimitiveValue() {
+		checkImmutable();
+		this.isNull = false;
+	}
+
+	@Override
+	public String toString() {
+		String nullState = "";
+		if (isNull()) {
+			nullState = "(NULL)";
+		}
+		return getClass().getSimpleName() + nullState + ": " + getValueAsString();
+	}
+
+}