[CARBONDATA-2997] Support read schema from index file and data file i…

…n CSDK

1.support readSchemaInIndexFile
2.support readSchemaInDataFile
3.support get field name and data type name
4.suppport get array child element data type name
5.can read schema when carbonreader has set ak,sk,endpoint
6.TODO: need support read scehma from S3 in the future

This closes #2807

docs/csdk-guide.md

@@ -39,6 +39,7 @@ and read data from S3 at main.cpp of CSDK module.  Finally, users need to
 release the memory and destroy JVM.
 
 ## API List
+### CarbonReader
 ```
     /**
      * create a CarbonReaderBuilder object for building carbonReader,
@@ -119,7 +120,7 @@ and write data to S3 at main.cpp of CSDK module.  Finally, users need to
 release the memory and destroy JVM.
 
 ## API List
-
+### CarbonWriter
 ```
     /**
      * create a CarbonWriterBuilder object for building carbonWriter,
@@ -187,4 +188,83 @@ release the memory and destroy JVM.
      * close the carbon Writer
      */
     void close();
+```
+
+### CarbonSchemaReader
+
+```
+    /**
+     * constructor with jni env
+     *
+     * @param env  jni env
+     */
+    CarbonSchemaReader(JNIEnv *env);
+```
+```
+    /**
+     * read Schema from Data File
+     *
+     * @param path Data File path
+     * @return carbon schema object
+     */
+    jobject readSchemaInDataFile(char *path);
+```
+```
+    /**
+     * read Schema from index File
+     *
+     * @param path index File path
+     * @return carbon schema object
+     */
+    jobject readSchemaInIndexFile(char *path);
+
+```
+###Schema
+``` 
+ /**
+     * constructor with jni env and carbon schema data
+     *
+     * @param env jni env
+     * @param schema  carbon schema data
+     */
+    Schema(JNIEnv *env, jobject schema);
+
+```
+```
+    /**
+     * get fields length of schema
+     *
+     * @return fields length
+     */
+    int getFieldsLength();
+
+```
+```
+    /**
+     * get field name by ordinal
+     *
+     * @param ordinal the data index of carbon schema
+     * @return ordinal field name
+     */
+    char *getFieldName(int ordinal);
+
+```
+```
+    /**
+     * get  field data type name by ordinal
+     *
+     * @param ordinal the data index of carbon schema
+     * @return ordinal field data type name
+     */
+    char *getFieldDataTypeName(int ordinal);
+
+```
+```
+    /**
+     * get  array child element data type name by ordinal
+     *
+     * @param ordinal the data index of carbon schema
+     * @return ordinal array child element data type name
+     */
+    char *getArrayElementTypeName(int ordinal);
 ```

store/CSDK/CMakeLists.txt

@@ -8,7 +8,7 @@ find_package(JNI REQUIRED)
 include_directories(${JNI_INCLUDE_DIRS})
 
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
-set(SOURCE_FILES src/CarbonReader.cpp src/CarbonReader.h test/main.cpp src/CarbonRow.h src/CarbonRow.cpp src/CarbonWriter.h  src/CarbonWriter.cpp)
+set(SOURCE_FILES src/CarbonReader.cpp src/CarbonReader.h test/main.cpp src/CarbonRow.h src/CarbonRow.cpp src/CarbonWriter.h  src/CarbonWriter.cpp src/CarbonSchemaReader.h src/CarbonSchemaReader.cpp src/Schema.h src/Schema.cpp)
 
 add_executable(CJDK ${SOURCE_FILES})
 get_filename_component(JAVA_JVM_LIBRARY_DIR ${JAVA_JVM_LIBRARY} DIRECTORY)

store/CSDK/src/CarbonReader.cpp

@@ -86,9 +86,9 @@ void CarbonReader::projection(int argc, char *argv[]) {
     }
     checkBuilder();
     jclass carbonReaderBuilderClass = jniEnv->GetObjectClass(carbonReaderBuilderObject);
-    jmethodID buildID = jniEnv->GetMethodID(carbonReaderBuilderClass, "projection",
+    jmethodID methodID = jniEnv->GetMethodID(carbonReaderBuilderClass, "projection",
         "([Ljava/lang/String;)Lorg/apache/carbondata/sdk/file/CarbonReaderBuilder;");
-    if (buildID == NULL) {
+    if (methodID == NULL) {
         throw std::runtime_error("Can't find the method in java: projection");
     }
     jclass objectArrayClass = jniEnv->FindClass("Ljava/lang/String;");
@@ -103,7 +103,7 @@ void CarbonReader::projection(int argc, char *argv[]) {
 
     jvalue args[1];
     args[0].l = array;
-    carbonReaderBuilderObject = jniEnv->CallObjectMethodA(carbonReaderBuilderObject, buildID, args);
+    carbonReaderBuilderObject = jniEnv->CallObjectMethodA(carbonReaderBuilderObject, methodID, args);
 }
 
 void CarbonReader::withHadoopConf(char *key, char *value) {
@@ -129,12 +129,12 @@ void CarbonReader::withHadoopConf(char *key, char *value) {
 jobject CarbonReader::build() {
     checkBuilder();
     jclass carbonReaderBuilderClass = jniEnv->GetObjectClass(carbonReaderBuilderObject);
-    jmethodID buildID = jniEnv->GetMethodID(carbonReaderBuilderClass, "build",
+    jmethodID methodID = jniEnv->GetMethodID(carbonReaderBuilderClass, "build",
         "()Lorg/apache/carbondata/sdk/file/CarbonReader;");
-    if (buildID == NULL) {
+    if (methodID == NULL) {
         throw std::runtime_error("Can't find the method in java: build");
     }
-    carbonReaderObject = jniEnv->CallObjectMethod(carbonReaderBuilderObject, buildID);
+    carbonReaderObject = jniEnv->CallObjectMethod(carbonReaderBuilderObject, methodID);
     if (jniEnv->ExceptionCheck()) {
         throw jniEnv->ExceptionOccurred();
     }

store/CSDK/src/CarbonSchemaReader.cpp

@@ -0,0 +1,68 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdexcept>
+#include "CarbonSchemaReader.h"
+
+CarbonSchemaReader::CarbonSchemaReader(JNIEnv *env) {
+    if (env == NULL) {
+        throw std::runtime_error("JNIEnv parameter can't be NULL.");
+    }
+    this->carbonSchemaReaderClass = env->FindClass("org/apache/carbondata/sdk/file/CarbonSchemaReader");
+    if (carbonSchemaReaderClass == NULL) {
+        throw std::runtime_error("Can't find the class in java: org/apache/carbondata/sdk/file/CarbonSchemaReader");
+    }
+    this->jniEnv = env;
+}
+
+jobject CarbonSchemaReader::readSchemaInDataFile(char *path) {
+    if (path == NULL) {
+        throw std::runtime_error("path parameter can't be NULL.");
+    }
+    jmethodID methodID = jniEnv->GetStaticMethodID(carbonSchemaReaderClass, "readSchemaInDataFile",
+        "(Ljava/lang/String;)Lorg/apache/carbondata/sdk/file/Schema;");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: readSchemaInDataFile");
+    }
+    jstring jPath = jniEnv->NewStringUTF(path);
+    jvalue args[1];
+    args[0].l = jPath;
+    jobject result = jniEnv->CallStaticObjectMethodA(carbonSchemaReaderClass, methodID, args);
+    if (jniEnv->ExceptionCheck()) {
+        throw jniEnv->ExceptionOccurred();
+    }
+    return result;
+}
+
+jobject CarbonSchemaReader::readSchemaInIndexFile(char *path) {
+    if (path == NULL) {
+        throw std::runtime_error("path parameter can't be NULL.");
+    }
+    jmethodID methodID = jniEnv->GetStaticMethodID(carbonSchemaReaderClass, "readSchemaInIndexFile",
+        "(Ljava/lang/String;)Lorg/apache/carbondata/sdk/file/Schema;");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: readSchemaInDataFile");
+    }
+    jstring jPath = jniEnv->NewStringUTF(path);
+    jvalue args[1];
+    args[0].l = jPath;
+    jobject result = jniEnv->CallStaticObjectMethodA(carbonSchemaReaderClass, methodID, args);
+    if (jniEnv->ExceptionCheck()) {
+        throw jniEnv->ExceptionOccurred();
+    }
+    return result;
+}

store/CSDK/src/CarbonSchemaReader.h

@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <jni.h>
+
+class CarbonSchemaReader {
+private:
+
+    /**
+     * jni env
+     */
+    JNIEnv *jniEnv;
+
+    /**
+     * carbonSchemaReader Class for get method id and call method
+     */
+    jclass carbonSchemaReaderClass;
+
+public:
+
+    /**
+     * constructor with jni env
+     *
+     * @param env  jni env
+     */
+    CarbonSchemaReader(JNIEnv *env);
+
+    /**
+     * read Schema from Data File
+     *
+     * @param path Data File path
+     * @return carbon schema object
+     */
+    jobject readSchemaInDataFile(char *path);
+
+    /**
+     * read Schema from index File
+     *
+     * @param path index File path
+     * @return carbon schema object
+     */
+    jobject readSchemaInIndexFile(char *path);
+
+};

store/CSDK/src/Schema.cpp

@@ -0,0 +1,92 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <jni.h>
+#include <stdexcept>
+#include "Schema.h"
+
+Schema::Schema(JNIEnv *env, jobject schema) {
+    if (env == NULL) {
+        throw std::runtime_error("JNIEnv parameter can't be NULL.");
+    }
+    if (schema == NULL) {
+        throw std::runtime_error("schema parameter can't be NULL.");
+    }
+    this->schemaClass = env->FindClass("org/apache/carbondata/sdk/file/Schema");
+    if (schemaClass == NULL) {
+        throw std::runtime_error("Can't find the class in java: org/apache/carbondata/sdk/file/Schema");
+    }
+    this->jniEnv = env;
+    this->schema = schema;
+}
+
+int Schema::getFieldsLength() {
+    jmethodID methodID = jniEnv->GetMethodID(schemaClass, "getFieldsLength",
+        "()I");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: getFieldsLength");
+    }
+    return jniEnv->CallIntMethod(schema, methodID);
+};
+
+void Schema::checkOrdinal(int ordinal) {
+    if (ordinal < 0) {
+        throw std::runtime_error("ordinal parameter can't be negative.");
+    }
+}
+
+char *Schema::getFieldName(int ordinal) {
+    checkOrdinal(ordinal);
+    jmethodID methodID = jniEnv->GetMethodID(schemaClass, "getFieldName",
+        "(I)Ljava/lang/String;");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: getFieldName");
+    }
+    jvalue args[1];
+    args[0].i = ordinal;
+    jobject fieldName = jniEnv->CallObjectMethodA(schema, methodID, args);
+    return (char *) jniEnv->GetStringUTFChars((jstring) fieldName, JNI_FALSE);
+};
+
+char *Schema::getFieldDataTypeName(int ordinal) {
+    checkOrdinal(ordinal);
+    jmethodID methodID = jniEnv->GetMethodID(schemaClass, "getFieldDataTypeName",
+        "(I)Ljava/lang/String;");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: getFieldDataTypeName");
+    }
+    jvalue args[1];
+    args[0].i = ordinal;
+    jobject fieldName = jniEnv->CallObjectMethodA(schema, methodID, args);
+    return (char *) jniEnv->GetStringUTFChars((jstring) fieldName, JNI_FALSE);
+};
+
+char *Schema::getArrayElementTypeName(int ordinal) {
+    checkOrdinal(ordinal);
+    jmethodID methodID = jniEnv->GetMethodID(schemaClass, "getArrayElementTypeName",
+        "(I)Ljava/lang/String;");
+    if (methodID == NULL) {
+        throw std::runtime_error("Can't find the method in java: getArrayElementTypeName");
+    }
+    jvalue args[1];
+    args[0].i = ordinal;
+    jobject fieldName = jniEnv->CallObjectMethodA(schema, methodID, args);
+    if (jniEnv->ExceptionCheck()) {
+        throw jniEnv->ExceptionOccurred();
+    }
+    return (char *) jniEnv->GetStringUTFChars((jstring) fieldName, JNI_FALSE);
+};