Add scanner isolation class loader to make each plugin non-conflicting.
The BE will get scanner classes by JNI call and use JniClassLoader load them.
In the last version，we always get canner classes from the system class path by default,
so it cannot isolate the classes for each scanner
1. If only read the partition columns, the `JniConnector` will produce empty required fields, so `HudiJniScanner` should read the "_hoodie_record_key" field at least to know how many rows in current hoodie split. Even if the `JniConnector` doesn't read this field, the call of `releaseTable` in `JniConnector` will reclaim the resource.
2. To prevent BE failure and exit, `JniConnector` should call release methods after `HudiJniScanner` is initialized. It should be noted that `VectorTable` is created lazily in `JniScanner`, so we don't need to reclaim the resource when `HudiJniScanner` is failed to initialize.
## Remaining works
Other jni readers like `paimon` and `maxcompute` may encounter the same problems, the jni reader need to handle this abnormal situation on its own, and currently this fix can only ensure that BE will not exit.
Add JNI metrics, for example:
```
- HudiJniScanner: 0ns
- FillBlockTime: 31.29ms
- GetRecordReaderTime: 1m5s
- JavaScanTime: 35s991ms
- OpenScannerTime: 1m6s
```
Add three common performance metrics for JNI scanner:
1. `OpenScannerTime`: Time to init and open JNI scanner
2. `JavaScanTime`: Time to scan data and insert into vector table in java side
3. `FillBlockTime`: Time to convert java vector table to c++ block
And support user defined metrics in java side, for example: `OpenScannerTime` is a long time for the open process, we want to determine which sub-process takes too much time, so we add `GetRecordReaderTime` in java side.
The user defined metrics in java side can be attached to BE profile automatically.
The java-udf module has become increasingly large and difficult to manage, making it inconvenient to package and use as needed. It needs to be split into multiple sub-modules, such as : java-commom、java-udf、jdbc-scanner、hudi-scanner、 paimon-scanner.
Co-authored-by: lexluo <lexluo@tencent.com>
This PR refactors the old way of writing data to JDBC External Table & JDBC Catalog, mainly including the following tasks
1. Continuing the work of @BePPPower 's PR #18594, changing the logic of splicing Inster sql to operating off-heap memory and using preparedStatement.set to write data logic to complete
2. Supplement the support written by largeint type, mainly to adapt to Java.Math.BigInteger, which uses binary operations
3. Delete the splicing SQL logic in the JDBC External Table & JDBC Catalog related written code
ToDo: Binary type，like bit,binary, blob...
Finally, special thanks to @BePPPower , @AshinGau for his work
Co-authored-by: Tiewei Fang <43782773+BePPPower@users.noreply.github.com>
Currently, there are some useless includes in the codebase. We can use a tool named include-what-you-use to optimize these includes. By using a strict include-what-you-use policy, we can get lots of benefits from it.
PR(#17960) has introduced vector table which can map java table to c++ block.
In some cases(java udf & jdbc exector), we should map c++ block to java table. This PR implements this function.
The memory structure of java vector table and c++ block is consistent,
so the implementation doesn't copy the block, just passes the memory address.
A framework that read data from jni scanner, which can support the data source from java ecosystem(java API).
## Java Interface
Java scanner should extends `org.apache.doris.jni.JniScanner`, implements the following methods:
```
// Initialize JniScanner
public abstract void open() throws IOException;
// Close JniScanner and release resources
public abstract void close() throws IOException;
// Scan data and save as vector table
public abstract int getNext() throws IOException;
```
See demo usage in `org.apache.doris.jni.MockJniScanner`
## c++ interface
C++ reader should use `doris::JniConnector` to get data from `org.apache.doris.jni.JniScanner`. See demo usage in `doris::MockJniReader`.
## Pushed-down predicates
Java scanner can get pushed-down predicates by `org.apache.doris.jni.vec.ScanPredicate`.
## Remaining works:
1. Implement complex nested types.
2. Read hudi MOR table as the end-to-end demo usage.
