apache/dubbo · error · RuntimeException

Failed to set field ${name} of pojo ${dest.getClass().getNam

Error message

Failed to set field ${name} of pojo ${dest.getClass().getName()} : ${e.getMessage()}

What it means

During realization, if no setter method is found for a property but a public field exists, PojoUtils uses field.set(dest, value) to assign the value directly. If this throws IllegalAccessException, it is wrapped in a RuntimeException naming the field and the target POJO class. This is distinct from error 268 which covers the method.invoke path.

Source

Thrown at dubbo-common/src/main/java/org/apache/dubbo/common/utils/PojoUtils.java:617

                                } else {
                                    Type ptype = method.getGenericParameterTypes()[0];
                                    value = realize1(value, method.getParameterTypes()[0], ptype, mapGeneric, history);
                                }
                                try {
                                    method.invoke(dest, value);
                                } catch (Exception e) {
                                    String exceptionDescription = "Failed to set pojo "
                                            + dest.getClass().getSimpleName() + " property " + name + " value "
                                            + value.getClass() + ", cause: " + e.getMessage();
                                    logger.error(COMMON_REFLECTIVE_OPERATION_FAILED, "", "", exceptionDescription, e);
                                    throw new RuntimeException(exceptionDescription, e);
                                }
                            } else if (field != null) {
                                value = realize1(value, field.getType(), field.getGenericType(), mapGeneric, history);
                                try {
                                    field.set(dest, value);
                                } catch (IllegalAccessException e) {
                                    throw new RuntimeException(
                                            "Failed to set field " + name + " of pojo "
                                                    + dest.getClass().getName() + " : " + e.getMessage(),
                                            e);
                                }
                            }
                        }
                    }
                }
                return dest;
            }
        }
        return pojo;
    }

    /**
     * Get key type for {@link Map} directly implemented by {@code clazz}.
     * If {@code clazz} does not implement {@link Map} directly, return {@code null}.
     *

View on GitHub (pinned to 3a3043227f)

Solutions

1. Add an 'opens <package>;' directive in module-info.java for the target class's module so Dubbo can access fields reflectively.
2. Add a standard setter for the property so PojoUtils uses method.invoke instead of field.set.
3. If using a SecurityManager, grant the necessary ReflectPermission.
4. Make the field public as a last resort.

Example fix

// before — module-info without opens
module com.example.dto { }
// after — open the package to Dubbo
module com.example.dto {
    opens com.example.dto to org.apache.dubbo;
}

// Ensure module/package is open before realizing
// On JDK 9+: add 'opens com.example.dto;' in module-info.java
// Programmatically check field accessibility:
Class<?> target = dest.getClass();
for (Field f : target.getDeclaredFields()) {
    if (!Modifier.isPublic(f)) {
        try { f.setAccessible(true); }
        catch (Exception ex) {
            throw new IllegalStateException(
                "Field " + f.getName() + " is not accessible in " + target.getName()
                + ". Add 'opens' to module-info or make public.", ex);
        }
    }
}

try {
    return PojoUtils.realize(map, targetClass);
} catch (RuntimeException e) {
    if (e.getCause() instanceof IllegalAccessException) {
        logger.error("Module access denied for {}. Add 'opens' directive.",
            targetClass.getModuleName());
    }
    throw e;
}

When it happens

Trigger: Calling PojoUtils.realize where the target object has a field (rather than a setter) for a property, and the field is not reflectively accessible — e.g. a non-public field in a class from another module without 'opens' declaration, or a SecurityManager that denies access even after makeAccessible.

Common situations: JDK 9+ module system where the target class's module does not 'opens' the package to Dubbo. Also when the class was loaded by a different classloader. The field-based assignment path is a fallback used when the class has no setter for the property.

Related errors

• Failed to set pojo ${dest.getClass().getSimpleName()} proper
• Illegal constructor: ${cls.getName()}
• `name` filed should be string!
• Unrecognized Type: ${fieldType.toString()}
• Can not merge result because missing method [ {merger} ] in

AI-assisted analysis of apache/dubbo@3a3043227f (2026-08-14). Data as JSON: /api/errors/28516e4fffa79a48. Report an issue: GitHub.