Fix: LAL compiler treated (tag("x") as Integer) + (tag("y") as Integer) as string concatenation instead of numeric addition.

docs/en/changes/changes.md

@@ -96,6 +96,7 @@
 * Fix: potential unexpected current directory inclusion in Docker OAP classpath.
 * MAL: add `safeDiv(divisor)` on `SampleFamily` that yields `0` when the divisor is `0` instead of `Infinity`/`NaN`. Replace `/` with `safeDiv(...)` in Envoy AI Gateway latency-average rules so `sum / count * 1000` no longer produces dropped or out-of-range samples when a counter is zero in a window.
 * Fix: `envoy-ai-gateway` metrics rules, make the metrics value return `0` when the divisor is `0`.
+* Fix: LAL compiler treated `(tag("x") as Integer) + (tag("y") as Integer)` as string concatenation instead of numeric addition. Expressions like `input_tokens + output_tokens < 10000` produced the concatenated string `"2589115"` rather than the integer sum `2704`, so token-threshold conditions never triggered `abort {}`. The compiler now detects all-numeric operands (cast to `Integer` or `Long`) and emits proper `long` arithmetic.
 
 #### UI
 * Add mobile menu icon and i18n labels for the iOS layer.

oap-server/analyzer/log-analyzer/src/main/java/org/apache/skywalking/oap/log/analyzer/v2/compiler/LALValueCodegen.java

@@ -45,6 +45,7 @@
  * def variable             myVar?.getAsString()               _def_myVar?.getAsString()
  * Parenthesized            (expr as String).trim()            h.toStr(...).trim()
  * String concat            "${log.service}:${parsed.code}"    "" + ... + ":" + ...
+ * Arithmetic sum           (tag("a") as Integer) + (tag("b") as Integer)  Long.valueOf((long) h.toInt(...) + (long) h.toInt(...))
  * }</pre>
  *
  * <p>Condition codegen ({@link #generateCondition}) handles {@code if}
@@ -342,16 +343,22 @@ static void generateValueAccess(final StringBuilder sb,
                                      final LALClassGenerator.GenCtx genCtx) {
         genCtx.clearExtraLogResult();
 
-        // Handle string concatenation (term1 + term2 + ...)
+        // Handle string concatenation or arithmetic addition (term1 + term2 + ...)
+        // When every part is a numeric cast (Integer/Long) or a number literal,
+        // emit integer/long arithmetic. Otherwise emit string concatenation.
         if (!value.getConcatParts().isEmpty()) {
-            sb.append("(\"\" + ");
-            for (int i = 0; i < value.getConcatParts().size(); i++) {
-                if (i > 0) {
-                    sb.append(" + ");
+            if (allPartsNumeric(value.getConcatParts())) {
+                generateArithmeticSum(sb, value.getConcatParts(), genCtx);
+            } else {
+                sb.append("(\"\" + ");
+                for (int i = 0; i < value.getConcatParts().size(); i++) {
+                    if (i > 0) {
+                        sb.append(" + ");
+                    }
+                    generateValueAccess(sb, value.getConcatParts().get(i), genCtx);
                 }
-                generateValueAccess(sb, value.getConcatParts().get(i), genCtx);
+                sb.append(")");
             }
-            sb.append(")");
             return;
         }
 
@@ -858,6 +865,82 @@ static void generateProcessRegistryCall(
 
     // ==================== Utility methods ====================
 
+    /**
+     * Returns {@code true} when every concat part is numeric — i.e. a
+     * parenthesized expression with an {@code Integer} or {@code Long} cast,
+     * or a bare number literal. If so, {@code +} is arithmetic, not string
+     * concatenation.
+     */
+    private static boolean allPartsNumeric(final List<LALScriptModel.ValueAccess> parts) {
+        for (final LALScriptModel.ValueAccess part : parts) {
+            if (part.isNumberLiteral()) {
+                continue;
+            }
+            if (part.getParenInner() != null && isNumericCast(part.getParenCast())) {
+                continue;
+            }
+            return false;
+        }
+        return true;
+    }
+
+    private static boolean isNumericCast(final String cast) {
+        return "Integer".equals(cast) || "Long".equals(cast);
+    }
+
+    /**
+     * Generates an arithmetic sum expression for a list of numeric parts.
+     * Always uses {@code long} arithmetic to avoid Javassist autoboxing
+     * restrictions (Javassist cannot pass a primitive {@code int/long} to a
+     * method that expects {@code Object}, e.g. {@code h.toLong(int)}).
+     *
+     * <p>Two outputs are produced:
+     * <ul>
+     *   <li>The raw {@code long} expression is stored in
+     *       {@code genCtx.lastRawChain} so that {@code generateNumericComparison}
+     *       can emit a direct primitive comparison without a
+     *       {@code h.toLong()} wrapper.</li>
+     *   <li>{@code Long.valueOf(rawExpr)} is appended to {@code sb} so that
+     *       non-comparison contexts (tag assignment, {@code h.toStr()}, etc.)
+     *       receive a boxed {@code Long} — a valid {@code Object}.</li>
+     * </ul>
+     *
+     * <p>Examples:
+     * <pre>{@code
+     * (tag("a") as Integer) + (tag("b") as Integer) < 10000
+     * rawExpr  → ((long) h.toInt(h.tagValue("a")) + (long) h.toInt(h.tagValue("b")))
+     * in sb    → Long.valueOf(((long) h.toInt(...) + (long) h.toInt(...)))
+     * comparison emits → rawExpr < 10000L   (via lastRawChain / primitiveNumeric path)
+     * }</pre>
+     */
+    private static void generateArithmeticSum(final StringBuilder sb,
+                                               final List<LALScriptModel.ValueAccess> parts,
+                                               final LALClassGenerator.GenCtx genCtx) {
+        final StringBuilder expr = new StringBuilder("(");
+        for (int i = 0; i < parts.size(); i++) {
+            if (i > 0) {
+                expr.append(" + ");
+            }
+            final LALScriptModel.ValueAccess part = parts.get(i);
+            if (part.isNumberLiteral()) {
+                expr.append(part.getSegments().get(0)).append("L");
+            } else if ("Long".equals(part.getParenCast())) {
+                generateCastedValueAccess(expr, part.getParenInner(), "Long", genCtx);
+            } else {
+                expr.append("(long) ");
+                generateCastedValueAccess(expr, part.getParenInner(), "Integer", genCtx);
+            }
+        }
+        expr.append(")");
+        final String rawExpr = expr.toString();
+        // Let generateNumericComparison skip h.toLong() and compare directly.
+        genCtx.lastResolvedType = long.class;
+        genCtx.lastRawChain = rawExpr;
+        genCtx.lastNullChecks = null;
+        // Box for Object contexts (h.toStr, h.toLong, def assignments, etc.)
+        sb.append("Long.valueOf(").append(rawExpr).append(")");
+    }
+
     /**
      * Appends a method call segment to the current expression chain.
      * Handles safe-navigation ({@code ?.method()}) by wrapping in a null

oap-server/analyzer/log-analyzer/src/test/java/org/apache/skywalking/oap/log/analyzer/v2/compiler/LALClassGeneratorConditionTest.java

@@ -19,6 +19,7 @@
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
@@ -292,6 +293,66 @@ void compileAndVerifyElseIfEmitsNestedBranches() throws Exception {
             + ifCount + " in: " + source);
     }
 
+    // ==================== Arithmetic addition in conditions ====================
+
+    @Test
+    void compileArithmeticSumOfIntegerTagsEmitsLongArithmetic() throws Exception {
+        // The envoy-ai-gateway token check pattern:
+        // (tag("input_tokens") as Integer) + (tag("output_tokens") as Integer) < 10000
+        // must do numeric addition (3033 < 10000 = true → abort),
+        // not string concat ("2872161" → 2872161 >= 10000 = false → no abort).
+        final String dsl = "filter {\n"
+            + "  if ((tag(\"a\") as Integer) + (tag(\"b\") as Integer) < 10000) {\n"
+            + "    abort {}\n"
+            + "  }\n"
+            + "  sink {}\n"
+            + "}";
+        compileAndAssert(dsl);
+        final String source = generator.generateSource(dsl);
+        assertTrue(source.contains("(long)"),
+            "Expected (long) promotion for Integer parts but got: " + source);
+        assertTrue(source.contains("h.toInt("),
+            "Expected h.toInt() for Integer cast but got: " + source);
+        assertFalse(source.contains("\"\" +"),
+            "Expected arithmetic addition, not string concat, but got: " + source);
+        // In a comparison context generateNumericComparison uses lastRawChain directly,
+        // so the comparison emits the raw long expression without Long.valueOf().
+        assertTrue(source.contains("< 10000L"),
+            "Expected '< 10000L' numeric comparison but got: " + source);
+    }
+
+    @Test
+    void compileArithmeticSumOfLongAndIntegerTagsEmitsLongArithmetic() throws Exception {
+        final String dsl = "filter {\n"
+            + "  if ((tag(\"a\") as Long) + (tag(\"b\") as Integer) < 10000) {\n"
+            + "    abort {}\n"
+            + "  }\n"
+            + "  sink {}\n"
+            + "}";
+        compileAndAssert(dsl);
+        final String source = generator.generateSource(dsl);
+        assertTrue(source.contains("h.toLong("),
+            "Expected h.toLong() for Long cast but got: " + source);
+        assertTrue(source.contains("(long)"),
+            "Expected (long) promotion for Integer parts but got: " + source);
+        assertFalse(source.contains("\"\" +"),
+            "Expected arithmetic addition, not string concat, but got: " + source);
+    }
+
+    @Test
+    void compileStringConcatWithPlusRemainsStringConcat() throws Exception {
+        final String dsl = "filter {\n"
+            + "  extractor {\n"
+            + "    tag 'key': tag(\"a\") + tag(\"b\")\n"
+            + "  }\n"
+            + "  sink {}\n"
+            + "}";
+        compileAndAssert(dsl);
+        final String source = generator.generateSource(dsl);
+        assertTrue(source.contains("\"\" +"),
+            "Expected string concatenation for uncast tags but got: " + source);
+    }
+
     // ==================== sourceAttribute() function ====================
 
     @Test