Changing Intent Ids to use explicit id assignment
Change-Id: I5a4bff87842c37a869e7691b353529eaefc929db
diff --git a/core/api/src/main/java/org/onlab/onos/core/IdBlock.java b/core/api/src/main/java/org/onlab/onos/core/IdBlock.java
new file mode 100644
index 0000000..c811e88
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/core/IdBlock.java
@@ -0,0 +1,87 @@
+package org.onlab.onos.core;
+
+import com.google.common.base.MoreObjects;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+/**
+ * A class representing an ID space.
+ */
+public final class IdBlock {
+ private final long start;
+ private final long size;
+
+ private final AtomicLong currentId;
+
+ /**
+ * Constructs a new ID block with the specified size and initial value.
+ *
+ * @param start initial value of the block
+ * @param size size of the block
+ * @throws IllegalArgumentException if the size is less than or equal to 0
+ */
+ public IdBlock(long start, long size) {
+ checkArgument(size > 0, "size should be more than 0, but %s", size);
+
+ this.start = start;
+ this.size = size;
+
+ this.currentId = new AtomicLong(start);
+ }
+
+ /**
+ * Returns the initial value.
+ *
+ * @return initial value
+ */
+ private long getStart() {
+ return start;
+ }
+
+ /**
+ * Returns the last value.
+ *
+ * @return last value
+ */
+ private long getEnd() {
+ return start + size - 1;
+ }
+
+ /**
+ * Returns the block size.
+ *
+ * @return block size
+ */
+ public long getSize() {
+ return size;
+ }
+
+ /**
+ * Returns the next ID in the block.
+ *
+ * @return next ID
+ * @throws UnavailableIdException if there is no available ID in the block.
+ */
+ public long getNextId() {
+ final long id = currentId.getAndIncrement();
+ if (id > getEnd()) {
+ throw new UnavailableIdException(String.format(
+ "used all IDs in allocated space (size: %d, end: %d, current: %d)",
+ size, getEnd(), id
+ ));
+ }
+
+ return id;
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(getClass())
+ .add("start", start)
+ .add("size", size)
+ .add("currentId", currentId)
+ .toString();
+ }
+}