added thread safety annotations (#445)

Author: rashtao

pom.xml

@@ -251,6 +251,12 @@
             <artifactId>jackson-dataformat-velocypack</artifactId>
             <optional>true</optional>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>jsr305</artifactId>
+            <version>3.0.2</version>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-classic</artifactId>

src/main/java/com/arangodb/ArangoCollection.java

@@ -23,6 +23,7 @@
 import com.arangodb.entity.*;
 import com.arangodb.model.*;
 
+import javax.annotation.concurrent.ThreadSafe;
 import java.util.Collection;
 
 /**
@@ -35,6 +36,7 @@
  * @see <a href="https://www.arangodb.com/docs/stable/http/collection.html">Documents API Documentation</a>
  */
 @SuppressWarnings("UnusedReturnValue")
+@ThreadSafe
 public interface ArangoCollection extends ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoDB.java

@@ -61,6 +61,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import javax.annotation.concurrent.ThreadSafe;
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.SSLContext;
 import java.io.InputStream;
@@ -85,6 +86,7 @@
  * @author Michele Rastelli
  */
 @SuppressWarnings("UnusedReturnValue")
+@ThreadSafe
 public interface ArangoDB extends ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoDatabase.java

@@ -27,6 +27,7 @@
 import com.arangodb.model.arangosearch.AnalyzerDeleteOptions;
 import com.arangodb.model.arangosearch.ArangoSearchCreateOptions;
 
+import javax.annotation.concurrent.ThreadSafe;
 import java.util.Collection;
 import java.util.Map;
 
@@ -39,6 +40,7 @@
  * @see <a href="https://www.arangodb.com/docs/stable/http/aql-query.html">Query API Documentation</a>
  */
 @SuppressWarnings("UnusedReturnValue")
+@ThreadSafe
 public interface ArangoDatabase extends ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoEdgeCollection.java

@@ -24,13 +24,16 @@
 import com.arangodb.entity.EdgeUpdateEntity;
 import com.arangodb.model.*;
 
+import javax.annotation.concurrent.ThreadSafe;
+
 /**
  * Interface for operations on ArangoDB edge collection level.
  *
  * @author Mark Vollmary
  * @see <a href="https://www.arangodb.com/docs/stable/http/gharial-edges.html">API Documentation</a>
  */
 @SuppressWarnings("UnusedReturnValue")
+@ThreadSafe
 public interface ArangoEdgeCollection extends ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoGraph.java

@@ -25,6 +25,7 @@
 import com.arangodb.model.GraphCreateOptions;
 import com.arangodb.model.VertexCollectionCreateOptions;
 
+import javax.annotation.concurrent.ThreadSafe;
 import java.util.Collection;
 
 /**
@@ -33,6 +34,7 @@
  * @author Mark Vollmary
  * @see <a href="https://www.arangodb.com/docs/stable/http/gharial.html">API Documentation</a>
  */
+@ThreadSafe
 public interface ArangoGraph extends ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoMetrics.java

@@ -20,12 +20,15 @@
 
 package com.arangodb;
 
+import javax.annotation.concurrent.ThreadSafe;
+
 /**
  * Interface for accessing metrics.
  *
  * @author Michele Rastelli
  * @since ArangoDB 3.9
  */
+@ThreadSafe
 public interface ArangoMetrics {
     /**
      * @return queue time metrics

src/main/java/com/arangodb/ArangoSearch.java

@@ -25,13 +25,16 @@
 import com.arangodb.model.arangosearch.ArangoSearchCreateOptions;
 import com.arangodb.model.arangosearch.ArangoSearchPropertiesOptions;
 
+import javax.annotation.concurrent.ThreadSafe;
+
 /**
  * Interface for operations on ArangoDB view level for ArangoSearch views.
  *
  * @author Mark Vollmary
  * @see <a href="https://www.arangodb.com/docs/stable/http/views.html">View API Documentation</a>
  * @since ArangoDB 3.4.0
  */
+@ThreadSafe
 public interface ArangoSearch extends ArangoView {
 
     /**

src/main/java/com/arangodb/ArangoSerializationAccessor.java

@@ -23,9 +23,12 @@
 import com.arangodb.internal.util.ArangoSerializationFactory.Serializer;
 import com.arangodb.util.ArangoSerialization;
 
+import javax.annotation.concurrent.ThreadSafe;
+
 /**
  * @author Mark Vollmary
  */
+@ThreadSafe
 public interface ArangoSerializationAccessor {
 
     /**

src/main/java/com/arangodb/ArangoVertexCollection.java

@@ -24,12 +24,15 @@
 import com.arangodb.entity.VertexUpdateEntity;
 import com.arangodb.model.*;
 
+import javax.annotation.concurrent.ThreadSafe;
+
 /**
  * Interface for operations on ArangoDB vertex collection level.
  *
  * @author Mark Vollmary
  * @see <a href="https://www.arangodb.com/docs/stable/http/gharial-vertices.html">API Documentation</a>
  */
+@ThreadSafe
 public interface ArangoVertexCollection extends ArangoSerializationAccessor {
 
     /**