(gravitino) branch main updated: [#8302] fix(cli): Fix potential NPE in ListTables (#8325)

[jmclean]

This is an automated email from the ASF dual-hosted git repository.

jmclean pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/gravitino.git


The following commit(s) were added to refs/heads/main by this push:
     new dc4cad8b41 [#8302] fix(cli): Fix potential NPE in ListTables (#8325)
dc4cad8b41 is described below

commit dc4cad8b411a89b759ed91237bed4d93d73b5161
Author: _.mung <wjdahr...@gmail.com>
AuthorDate: Fri Aug 29 07:06:17 2025 +0900

    [#8302] fix(cli): Fix potential NPE in ListTables (#8325)
    
    ### What changes were proposed in this pull request?
    
    This pull request addresses issue #8302 by adding null checks in
    ListTables.java to prevent potential NullPointerExceptions.
    The key changes include:
    - Checking if the tableCatalog object is null before it is used.
    - Checking if the tables array is null after calling listTables() and
    before its properties are accessed.
    
    ### Why are the changes needed?
    
    Previously, the list tables command would crash with a
    NullPointerException if it was executed with a non-existent catalog or
    if the listTables operation returned null for any reason. This change
    ensures the command handles these scenarios gracefully by exiting
    cleanly instead of crashing, which improves the overall stability and
    reliability of the CLI tool.
    
    Fixes: #8302
    
    ### Does this PR introduce _any_ user-facing change?
    
    No. This PR does not introduce any user-facing changes. It is a bug fix
    that improves the stability and error handling of the CLI.
    
    ### How was this patch tested?
    
    This patch was tested by running a full build of the project, including
    all unit and integration tests, using the ./gradlew clean build command.
    The build completed successfully, and all existing tests passed,
    confirming that the changes did not introduce any regressions.
    
    The fix itself was manually reasoned about to ensure it correctly
    handles the null-checking logic, preventing the NullPointerException. No
    new tests were added as this change is a simple safeguard and does not
    alter the existing logic of the command.
---
 .../java/org/apache/gravitino/cli/commands/ListTables.java   | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git 
a/clients/cli/src/main/java/org/apache/gravitino/cli/commands/ListTables.java 
b/clients/cli/src/main/java/org/apache/gravitino/cli/commands/ListTables.java
index 1f098efce7..463ff732b0 100644
--- 
a/clients/cli/src/main/java/org/apache/gravitino/cli/commands/ListTables.java
+++ 
b/clients/cli/src/main/java/org/apache/gravitino/cli/commands/ListTables.java
@@ -25,6 +25,7 @@ import org.apache.gravitino.Namespace;
 import org.apache.gravitino.cli.CommandContext;
 import org.apache.gravitino.rel.Column;
 import org.apache.gravitino.rel.Table;
+import org.apache.gravitino.rel.TableCatalog;
 
 /** List the names of all tables in a schema. */
 public class ListTables extends TableCommand {
@@ -50,13 +51,20 @@ public class ListTables extends TableCommand {
     NameIdentifier[] tables = null;
     Namespace name = Namespace.of(schema);
 
+    TableCatalog catalog = tableCatalog();
+    if (catalog == null) {
+      // The error message is already printed in the tableCatalog() method.
+      // We just need to exit here.
+      return;
+    }
+
     try {
-      tables = tableCatalog().listTables(name);
+      tables = catalog.listTables(name);
     } catch (Exception exp) {
       exitWithError(exp.getMessage());
     }
 
-    if (tables.length == 0) {
+    if (tables == null || tables.length == 0) {
       printInformation("No tables exist.");
       return;
     }