聊聊rocketmq的RemotingCommandException
- 2019 年 12 月 18 日
- 笔记
序
本文主要研究一下rocketmq的RemotingCommandException
RemotingCommandException
rocketmq-all-4.6.0-source-release/remoting/src/main/java/org/apache/rocketmq/remoting/exception/RemotingCommandException.java
public class RemotingCommandException extends RemotingException { private static final long serialVersionUID = -6061365915274953096L; public RemotingCommandException(String message) { super(message, null); } public RemotingCommandException(String message, Throwable cause) { super(message, cause); } }
- RemotingCommandException继承了RemotingException
RemotingCommand
rocketmq-all-4.6.0-source-release/remoting/src/main/java/org/apache/rocketmq/remoting/protocol/RemotingCommand.java
public class RemotingCommand { //...... public CommandCustomHeader decodeCommandCustomHeader( Class<? extends CommandCustomHeader> classHeader) throws RemotingCommandException { CommandCustomHeader objectHeader; try { objectHeader = classHeader.newInstance(); } catch (InstantiationException e) { return null; } catch (IllegalAccessException e) { return null; } if (this.extFields != null) { Field[] fields = getClazzFields(classHeader); for (Field field : fields) { if (!Modifier.isStatic(field.getModifiers())) { String fieldName = field.getName(); if (!fieldName.startsWith("this")) { try { String value = this.extFields.get(fieldName); if (null == value) { if (!isFieldNullable(field)) { throw new RemotingCommandException("the custom field <" + fieldName + "> is null"); } continue; } field.setAccessible(true); String type = getCanonicalName(field.getType()); Object valueParsed; if (type.equals(STRING_CANONICAL_NAME)) { valueParsed = value; } else if (type.equals(INTEGER_CANONICAL_NAME_1) || type.equals(INTEGER_CANONICAL_NAME_2)) { valueParsed = Integer.parseInt(value); } else if (type.equals(LONG_CANONICAL_NAME_1) || type.equals(LONG_CANONICAL_NAME_2)) { valueParsed = Long.parseLong(value); } else if (type.equals(BOOLEAN_CANONICAL_NAME_1) || type.equals(BOOLEAN_CANONICAL_NAME_2)) { valueParsed = Boolean.parseBoolean(value); } else if (type.equals(DOUBLE_CANONICAL_NAME_1) || type.equals(DOUBLE_CANONICAL_NAME_2)) { valueParsed = Double.parseDouble(value); } else { throw new RemotingCommandException("the custom field <" + fieldName + "> type is not supported"); } field.set(objectHeader, valueParsed); } catch (Throwable e) { log.error("Failed field [{}] decoding", fieldName, e); } } } } objectHeader.checkFields(); } return objectHeader; } private boolean isFieldNullable(Field field) { if (!NULLABLE_FIELD_CACHE.containsKey(field)) { Annotation annotation = field.getAnnotation(CFNotNull.class); synchronized (NULLABLE_FIELD_CACHE) { NULLABLE_FIELD_CACHE.put(field, annotation == null); } } return NULLABLE_FIELD_CACHE.get(field); } //...... }
- decodeCommandCustomHeader方法在value为null且标注了CFNotNull时候以及解析不到field.getType()时会抛出RemotingCommandException
小结
RemotingCommand的decodeCommandCustomHeader方法在value为null且标注了CFNotNull时候以及解析不到field.getType()时会抛出RemotingCommandException
