com.datastax.data.dataset.io.schema.DataSetIOUtility Maven / Gradle / Ivy
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package com.datastax.data.dataset.io.schema;
import java.io.BufferedWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.math.BigDecimal;
import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.sql.Types;
import java.util.*;
import java.util.logging.Logger;
public class DataSetIOUtility {
private static final Logger LOG = Logger.getLogger(DataSetIOUtility.class.getName());
private DataSetIOUtility() {
}
public static Class getType(int type) {
switch (type) {
case Types.ARRAY:
case Types.DISTINCT:
case Types.JAVA_OBJECT:
case Types.NULL:
case Types.OTHER:
case Types.REF:
case Types.STRUCT:
case Types.DATALINK:
return Object.class;
case Types.BINARY:
case Types.BIT:
case Types.BOOLEAN:
return Boolean.class;
case Types.BIGINT:
case Types.SMALLINT:
case Types.TINYINT:
case Types.INTEGER:
return Integer.class;
case Types.BLOB:
case Types.LONGVARBINARY:
case Types.VARBINARY:
return byte[].class;
case Types.CHAR:
return Character.class;
case Types.CLOB:
return char[].class;
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP:
return Date.class;
case Types.DECIMAL:
case Types.DOUBLE:
case Types.FLOAT:
case Types.NUMERIC:
case Types.REAL:
return BigDecimal.class;
case Types.VARCHAR:
case Types.LONGVARCHAR:
return String.class;
default:
LOG.warning("Unsupported JDBC type; type is unknown, so mapping to Object.class. Type value was " + type);
return Object.class;
}
}
public static Map> extractTableList(String... tableNames) {
Map> tables = new HashMap>(5);
for (String name : tableNames) {
int dotIdx = name.indexOf(".");
if (dotIdx != -1) {
String table = name.substring(0, dotIdx);
String col = name.substring(dotIdx + 1);
if (!tables.containsKey(table)) {
tables.put(table, new HashSet());
}
if (tables.get(table) != null) {
tables.get(table).add(col);
}
} else {
tables.put(name, null);
}
}
return tables;
}
public static String getDefaultSchemaName(DatabaseMetaData databaseMetaData) {
String defaultSchemaName = null;
try {
ResultSet rs = databaseMetaData.getSchemas();
boolean found = false;
while ( rs.next() && ! found) {
found = rs.getBoolean("IS_DEFAULT");
if ( found ) defaultSchemaName = rs.getString("TABLE_SCHEM");
}
} catch (Exception e) {
defaultSchemaName = null;
}
return defaultSchemaName;
}
public static List extractColumn(ResultSet tableResultSet, String columnName) {
List tables = new ArrayList();
try {
while (tableResultSet.next()) {
tables.add(tableResultSet.getString(columnName));
}
} catch (Exception e) {
e.printStackTrace();
}
return tables;
}
public static void dumpCatalogDetails(DatabaseMetaData databaseMetaData, PrintWriter pw) {
try {
pw.println(databaseMetaData.getCatalogTerm());
ResultSet rs = databaseMetaData.getCatalogs();
while ( rs.next()) {
int cnt = rs.getMetaData().getColumnCount();
while ( --cnt >= 0 ) {
pw.println("Col: " + rs.getMetaData().getColumnName(cnt));
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
private static PrintWriter getPrintWriter(Writer writer) {
if ( writer instanceof PrintWriter) {
return (PrintWriter)writer;
} else {
return new PrintWriter(new BufferedWriter(writer));
}
}
}