如何在JDBC中捕获特定的exception？
如何在JDBC中捕获特定的exception？ 示例：主键exception或外键exception。
SQLException包含与exception相关的一些特定于数据库的信息。 从文档：
每个SQLException都提供了几种信息：
1）描述错误的字符串。 这用作Java Exception消息，可通过getMesage方法获得。
2）“SQLstate”字符串，遵循XOPEN SQLstate约定或SQL 99约定。 SQLState字符串的值在相应的规范中描述。 DatabaseMetaData方法getSQLStateType可用于发现驱动程序是返回XOPEN类型还是SQL 99类型。
3）特定于每个供应商的整数错误代码。 通常这将是底层数据库返回的实际错误代码。
4）链接到下一个例外。 这可用于提供其他错误信息。
处理SQLException的最佳和独立于数据库的方法更具体地是确定可以通过SQLException#getSQLState()获得的SQL状态代码。 SQLState是一个5-char代码，其中前两个在所有DB中是通用的，后三个可能根据DB和/或特定条件而不同。 这是规范的摘录：
- 02：没有数据
- 07：动态SQL错误
- 08：连接exception
- 0A：不支持function
- 21：基数违规
- 22：数据exception
- 23：完整性约束违规
- 24：游标状态无效
- 25：无效的交易状态
- 26：无效的SQL语句名称
- 28：无效的授权规范
- 2B：依赖特权描述符仍然存在
- 2C：无效的字符集名称
- 2D：无效的交易终止
- 2E：连接名称无效
- 33：无效的SQL描述符名称
- 34：游标名称无效
- 35：条件号无效
- 3C：模糊游标名称
- 3D：目录名称无效
- 3F：模式名称无效
因此，要确定SQLexception是否由约束违规引起，您可以在（虚构） SQLUtil类中执行以下SQLUtil ：
public static boolean isConstraintViolation(SQLException e) { return e.getSQLState().startsWith("23"); }
Brian是对的，因为几乎任何JDBC问题都会引发SQLException。 这就是为什么JDBC如此烦人的部分原因。 Spring库JDBC帮助程序提供了一个exception转换器来查看SQLCode，SQLState等，并抛出相应的DataAccessException 。 有许多这些exception类，它们可以让您更好地了解出现了什么问题，例如DataIntegrityViolationException，DataSourceLookupFailureException，PermissionDeniedDataAccessException等。
继BalusC的答案之后 ，这里是SQL：2011标准规定的所有类和子类的更完整的最新列表。 我刚刚为jOOQ的SQLStateSubclass的Javadoc汇总了这个列表。
+----+-----------------------------------------------------------+-----+--------------------------------------------------------------+ | Class and class description | Subclass and subclass description | +----+-----------------------------------------------------------+-----+--------------------------------------------------------------+ | 00 | Successful completion | 000 | No subclass | | 01 | Warning | 000 | No subclass | | 01 | Warning | 001 | Cursor operation conflict | | 01 | Warning | 002 | Disconnect error | | 01 | Warning | 003 | Null value eliminated in set function | | 01 | Warning | 004 | String data, right truncation | | 01 | Warning | 005 | Insufficient item descriptor areas | | 01 | Warning | 006 | Privilege not revoked | | 01 | Warning | 007 | Privilege not granted | | 01 | Warning | 009 | Search condition too long for information schema | | 01 | Warning | 00A | Query expression too long for information schema | | 01 | Warning | 00B | Default value too long for information schema | | 01 | Warning | 00C | Result sets returned | | 01 | Warning | 00D | Additional result sets returned | | 01 | Warning | 00E | Attempt to return too many result sets | | 01 | Warning | 00F | Statement too long for information schema | | 01 | Warning | 012 | Invalid number of conditions | | 01 | Warning | 02F | Array data, right truncation | | 02 | No data | 000 | No subclass | | 02 | No data | 001 | No additional result sets returned | | 07 | Dynamic SQL Error | 000 | No subclass | | 07 | Dynamic SQL Error | 001 | Using clause does not match dynamic parameter specifications | | 07 | Dynamic SQL Error | 002 | Using clause does not match target specifications | | 07 | Dynamic SQL Error | 003 | Cursor specification cannot be executed | | 07 | Dynamic SQL Error | 004 | Using clause required for dynamic parameters | | 07 | Dynamic SQL Error | 005 | Prepared statement not a cursor specification | | 07 | Dynamic SQL Error | 006 | Restricted data type attribute violation | | 07 | Dynamic SQL Error | 007 | Using clause required for result fields | | 07 | Dynamic SQL Error | 008 | Invalid descriptor count | | 07 | Dynamic SQL Error | 009 | Invalid descriptor index | | 07 | Dynamic SQL Error | 00B | Data type transform function violation | | 07 | Dynamic SQL Error | 00C | Undefined DATA value | | 07 | Dynamic SQL Error | 00D | Invalid DATA target | | 07 | Dynamic SQL Error | 00E | Invalid LEVEL value | | 07 | Dynamic SQL Error | 00F | Invalid DATETIME_INTERVAL_CODE | | 08 | Connection exception | 000 | No subclass | | 08 | Connection exception | 001 | SQL-client unable to establish SQL-connection | | 08 | Connection exception | 002 | Connection name in use | | 08 | Connection exception | 003 | Connection does not exist | | 08 | Connection exception | 004 | SQL-server rejected establishment of SQL-connection | | 08 | Connection exception | 006 | Connection failure | | 08 | Connection exception | 007 | Transaction resolution unknown | | 09 | Triggered action exception | 000 | No subclass | | 0A | Feature not supported | 000 | No subclass | | 0A | Feature not supported | 001 | Multiple server transactions | | 0D | Invalid target type specification | 000 | No subclass | | 0E | Invalid schema name list specification | 000 | No subclass | | 0F | Locator exception | 000 | No subclass | | 0F | Locator exception | 001 | Invalid specification | | 0L | Invalid grantor | 000 | No subclass | | 0M | Invalid SQL-invoked procedure reference | 000 | No subclass | | 0P | Invalid role specification | 000 | No subclass | | 0S | Invalid transform group name specification | 000 | No subclass | | 0T | Target table disagrees with cursor specification | 000 | No subclass | | 0U | Attempt to assign to non-updatable column | 000 | No subclass | | 0V | Attempt to assign to ordering column | 000 | No subclass | | 0W | Prohibited statement encountered during trigger execution | 000 | No subclass | | 0W | Prohibited statement encountered during trigger execution | 001 | Modify table modified by data change delta table | | 0Z | Diagnostics exception | 000 | No subclass | | 0Z | Diagnostics exception | 001 | Maximum number of stacked diagnostics areas exceeded | | 21 | Cardinality violation | 000 | No subclass | | 22 | Data exception | 000 | No subclass | | 22 | Data exception | 001 | String data, right truncation | | 22 | Data exception | 002 | Null value, no indicator parameter | | 22 | Data exception | 003 | Numeric value out of range | | 22 | Data exception | 004 | Null value not allowed | | 22 | Data exception | 005 | Error in assignment | | 22 | Data exception | 006 | Invalid interval format | | 22 | Data exception | 007 | Invalid datetime format | | 22 | Data exception | 008 | Datetime field overflow | | 22 | Data exception | 009 | Invalid time zone displacement value | | 22 | Data exception | 00B | Escape character conflict | | 22 | Data exception | 00C | Invalid use of escape character | | 22 | Data exception | 00D | Invalid escape octet | | 22 | Data exception | 00E | Null value in array target | | 22 | Data exception | 00F | Zero-length character string | | 22 | Data exception | 00G | Most specific type mismatch | | 22 | Data exception | 00H | Sequence generator limit exceeded | | 22 | Data exception | 00P | Interval value out of range | | 22 | Data exception | 00Q | Multiset value overflow | | 22 | Data exception | 010 | Invalid indicator parameter value | | 22 | Data exception | 011 | Substring error | | 22 | Data exception | 012 | Division by zero | | 22 | Data exception | 013 | Invalid preceding or following size in window function | | 22 | Data exception | 014 | Invalid argument for NTILE function | | 22 | Data exception | 015 | Interval field overflow | | 22 | Data exception | 016 | Invalid argument for NTH_VALUE function | | 22 | Data exception | 018 | Invalid character value for cast | | 22 | Data exception | 019 | Invalid escape character | | 22 | Data exception | 01B | Invalid regular expression | | 22 | Data exception | 01C | Null row not permitted in table | | 22 | Data exception | 01E | Invalid argument for natural logarithm | | 22 | Data exception | 01F | Invalid argument for power function | | 22 | Data exception | 01G | Invalid argument for width bucket function | | 22 | Data exception | 01H | Invalid row version | | 22 | Data exception | 01S | Invalid XQuery regular expression | | 22 | Data exception | 01T | Invalid XQuery option flag | | 22 | Data exception | 01U | Attempt to replace a zero-length string | | 22 | Data exception | 01V | Invalid XQuery replacement string | | 22 | Data exception | 01W | Invalid row count in fetch first clause | | 22 | Data exception | 01X | Invalid row count in result offset clause | | 22 | Data exception | 020 | Invalid period value | | 22 | Data exception | 021 | Character not in repertoire | | 22 | Data exception | 022 | Indicator overflow | | 22 | Data exception | 023 | Invalid parameter value | | 22 | Data exception | 024 | Unterminated C string | | 22 | Data exception | 025 | Invalid escape sequence | | 22 | Data exception | 026 | String data, length mismatch | | 22 | Data exception | 027 | Trim error | | 22 | Data exception | 029 | Noncharacter in UCS string | | 22 | Data exception | 02D | Null value substituted for mutator subject parameter | | 22 | Data exception | 02E | Array element error | | 22 | Data exception | 02F | Array data, right truncation | | 22 | Data exception | 02G | Invalid repeat argument in sample clause | | 22 | Data exception | 02H | Invalid sample size | | 23 | Integrity constraint violation | 000 | No subclass | | 23 | Integrity constraint violation | 001 | Restrict violation | | 24 | Invalid cursor state | 000 | No subclass | | 25 | Invalid transaction state | 000 | No subclass | | 25 | Invalid transaction state | 001 | Active SQL-transaction | | 25 | Invalid transaction state | 002 | Branch transaction already active | | 25 | Invalid transaction state | 003 | Inappropriate access mode for branch transaction | | 25 | Invalid transaction state | 004 | Inappropriate isolation level for branch transaction | | 25 | Invalid transaction state | 005 | No active SQL-transaction for branch transaction | | 25 | Invalid transaction state | 006 | Read-only SQL-transaction | | 25 | Invalid transaction state | 007 | Schema and data statement mixing not supported | | 25 | Invalid transaction state | 008 | Held cursor requires same isolation level | | 26 | Invalid SQL statement name | 000 | No subclass | | 27 | Triggered data change violation | 000 | No subclass | | 27 | Triggered data change violation | 001 | Modify table modified by data change delta table | | 28 | Invalid authorization specification | 000 | No subclass | | 2B | Dependent privilege descriptors still exist | 000 | No subclass | | 2C | Invalid character set name | 000 | No subclass | | 2C | Invalid character set name | 001 | Cannot drop SQL-session default character set | | 2D | Invalid transaction termination | 000 | No subclass | | 2E | Invalid connection name | 000 | No subclass | | 2F | SQL routine exception | 000 | No subclass | | 2F | SQL routine exception | 002 | Modifying SQL-data not permitted | | 2F | SQL routine exception | 003 | Prohibited SQL-statement attempted | | 2F | SQL routine exception | 004 | Reading SQL-data not permitted | | 2F | SQL routine exception | 005 | Function executed no return statement | | 2H | Invalid collation name | 000 | No subclass | | 30 | Invalid SQL statement identifier | 000 | No subclass | | 33 | Invalid SQL descriptor name | 000 | No subclass | | 34 | Invalid cursor name | 000 | No subclass | | 35 | Invalid condition number | 000 | No subclass | | 36 | Cursor sensitivity exception | 000 | No subclass | | 36 | Cursor sensitivity exception | 001 | request rejected | | 36 | Cursor sensitivity exception | 002 | request failed | | 38 | External routine exception | 000 | No subclass | | 38 | External routine exception | 001 | Containing SQL not permitted | | 38 | External routine exception | 002 | Modifying SQL-data not permitted | | 38 | External routine exception | 003 | Prohibited SQL-statement attempted | | 38 | External routine exception | 004 | Reading SQL-data not permitted | | 39 | External routine invocation exception | 000 | No subclass | | 39 | External routine invocation exception | 004 | Null value not allowed | | 3B | Savepoint exception | 000 | No subclass | | 3B | Savepoint exception | 001 | Invalid specification | | 3B | Savepoint exception | 002 | Too many | | 3C | Ambiguous cursor name | 000 | No subclass | | 3D | Invalid catalog name | 000 | No subclass | | 3F | Invalid schema name | 000 | No subclass | | 40 | Transaction rollback | 000 | No subclass | | 40 | Transaction rollback | 001 | Serialization failure | | 40 | Transaction rollback | 002 | Integrity constraint violation | | 40 | Transaction rollback | 003 | Statement completion unknown | | 40 | Transaction rollback | 004 | Triggered action exception | | 42 | Syntax error or access rule violation | 000 | No subclass | | 44 | With check option violation | 000 | No subclass | | HZ | Remote database access | 000 | No subclass | +----+-----------------------------------------------------------+-----+--------------------------------------------------------------+
您还可以使用getErrorCode()方法正确处理exception，尤其在使用存储过程或函数时有用，并且您有自己的自定义错误代码。
对于具有类似背景的人来说，这可能会有所帮助。
在catch子句中，您可以更具体地处理该Exception 。
try { // Your code here } catch(SQLException ex){ if(ex instanceof SQLIntegrityConstraintViolationException) { // Handle Here } }