chore: Adds FDv2 PayloadProcessor

lib/shared/internal/src/main/java/com/launchdarkly/sdk/internal/fdv2/processor/Payload.java

@@ -0,0 +1,130 @@
+package com.launchdarkly.sdk.internal.fdv2.processor;
+
+import java.util.List;
+
+import static java.util.Collections.emptyList;
+
+/**
+ * Represents a collection of updates from the FDv2 services. If basis is true, the set of updates
+ * represents the complete state of the payload.
+ */
+public final class Payload {
+    private String id;
+    private int version;
+    private String state;
+    private boolean basis;
+    private List<Update> updates;
+
+    /**
+     * Default constructor.
+     */
+    public Payload() {}
+
+    /**
+     * Constructs a Payload with the specified properties.
+     *
+     * @param id the payload identifier
+     * @param version the payload version
+     * @param state the payload state (optional)
+     * @param basis whether this represents the complete state
+     * @param updates the list of updates
+     */
+    public Payload(String id, int version, String state, boolean basis, List<Update> updates) {
+        this.id = id;
+        this.version = version;
+        this.state = state;
+        this.basis = basis;
+        this.updates = updates;
+    }
+
+    /**
+     * Returns the payload identifier.
+     *
+     * @return the payload identifier
+     */
+    public String getId() {
+        return id;
+    }
+
+    /**
+     * Sets the payload identifier.
+     *
+     * @param id the payload identifier
+     */
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    /**
+     * Returns the payload version.
+     *
+     * @return the payload version
+     */
+    public int getVersion() {
+        return version;
+    }
+
+    /**
+     * Sets the payload version.
+     *
+     * @param version the payload version
+     */
+    public void setVersion(int version) {
+        this.version = version;
+    }
+
+    /**
+     * Returns the payload state.
+     *
+     * @return the payload state, or null if not present
+     */
+    public String getState() {
+        return state;
+    }
+
+    /**
+     * Sets the payload state.
+     *
+     * @param state the payload state
+     */
+    public void setState(String state) {
+        this.state = state;
+    }
+
+    /**
+     * Returns whether this represents the complete state.
+     *
+     * @return true if this represents the complete state, false otherwise
+     */
+    public boolean isBasis() {
+        return basis;
+    }
+
+    /**
+     * Sets whether this represents the complete state.
+     *
+     * @param basis true if this represents the complete state, false otherwise
+     */
+    public void setBasis(boolean basis) {
+        this.basis = basis;
+    }
+
+    /**
+     * Returns the list of updates.
+     *
+     * @return the list of updates (never null)
+     */
+    public List<Update> getUpdates() {
+        return updates == null ? emptyList() : updates;
+    }
+
+    /**
+     * Sets the list of updates.
+     *
+     * @param updates the list of updates
+     */
+    public void setUpdates(List<Update> updates) {
+        this.updates = updates;
+    }
+}
+