[FLINK-6864] [core] Fix confusing "invalid POJO type" messages from TypeExtractor
This closes #4574 Project: http://git-wip-us.apache.org/repos/asf/flink/repo Commit: http://git-wip-us.apache.org/repos/asf/flink/commit/450b4241 Tree: http://git-wip-us.apache.org/repos/asf/flink/tree/450b4241 Diff: http://git-wip-us.apache.org/repos/asf/flink/diff/450b4241 Branch: refs/heads/master Commit: 450b4241404055ed6638e354be421b83380827c5 Parents: 53f2c1c Author: zjureel <zjur...@gmail.com> Authored: Wed Aug 23 10:30:31 2017 +0800 Committer: Greg Hogan <c...@greghogan.com> Committed: Tue Nov 28 15:59:51 2017 -0500 ---------------------------------------------------------------------- docs/dev/types_serialization.md | 3 +++ .../flink/api/java/typeutils/TypeExtractor.java | 24 +++++++++++++++----- 2 files changed, 21 insertions(+), 6 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/flink/blob/450b4241/docs/dev/types_serialization.md ---------------------------------------------------------------------- diff --git a/docs/dev/types_serialization.md b/docs/dev/types_serialization.md index 1f0c466..d865d8e 100644 --- a/docs/dev/types_serialization.md +++ b/docs/dev/types_serialization.md @@ -115,6 +115,9 @@ conditions are fulfilled: or have a public getter- and a setter- method that follows the Java beans naming conventions for getters and setters. +Note that when a user-defined data type can't be recognized as a POJO type, it must be processed as GenericType and +serialized with Kryo. + #### Creating a TypeInformation or TypeSerializer http://git-wip-us.apache.org/repos/asf/flink/blob/450b4241/flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java ---------------------------------------------------------------------- diff --git a/flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java b/flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java index 8ea2e1a..4767838 100644 --- a/flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java +++ b/flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java @@ -1885,7 +1885,9 @@ public class TypeExtractor { ParameterizedType parameterizedType, TypeInformation<IN1> in1Type, TypeInformation<IN2> in2Type) { if (!Modifier.isPublic(clazz.getModifiers())) { - LOG.info("Class " + clazz.getName() + " is not public, cannot treat it as a POJO type. Will be handled as GenericType"); + LOG.info("Class " + clazz.getName() + " is not public so it cannot be used as a POJO type " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return new GenericTypeInfo<OUT>(clazz); } @@ -1900,7 +1902,9 @@ public class TypeExtractor { List<Field> fields = getAllDeclaredFields(clazz, false); if (fields.size() == 0) { - LOG.info("No fields detected for " + clazz + ". Cannot be used as a PojoType. Will be handled as GenericType"); + LOG.info("No fields were detected for " + clazz + " so it cannot be used as a POJO type " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return new GenericTypeInfo<OUT>(clazz); } @@ -1908,7 +1912,9 @@ public class TypeExtractor { for (Field field : fields) { Type fieldType = field.getGenericType(); if(!isValidPojoField(field, clazz, typeHierarchy)) { - LOG.info(clazz + " is not a valid POJO type because not all fields are valid POJO fields."); + LOG.info("Class " + clazz + " cannot be used as a POJO type because not all fields are valid POJO fields, " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return null; } try { @@ -1934,7 +1940,9 @@ public class TypeExtractor { List<Method> methods = getAllDeclaredMethods(clazz); for (Method method : methods) { if (method.getName().equals("readObject") || method.getName().equals("writeObject")) { - LOG.info(clazz+" contains custom serialization methods we do not call."); + LOG.info("Class " + clazz + " contains custom serialization methods we do not call, so it cannot be used as a POJO type " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return null; } } @@ -1949,12 +1957,16 @@ public class TypeExtractor { LOG.info(clazz + " is abstract or an interface, having a concrete " + "type can increase performance."); } else { - LOG.info(clazz + " must have a default constructor to be used as a POJO."); + LOG.info(clazz + " is missing a default constructor so it cannot be used as a POJO type " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return null; } } if(defaultConstructor != null && !Modifier.isPublic(defaultConstructor.getModifiers())) { - LOG.info("The default constructor of " + clazz + " should be Public to be used as a POJO."); + LOG.info("The default constructor of " + clazz + " is not Public so it cannot be used as a POJO type " + + "and must be processed as GenericType. Please read the Flink documentation " + + "on \"Data Types & Serialization\" for details of the effect on performance."); return null; }
