[SQOOP-1533] Java 8 : sqoop import --create-hcatalog-table for mysql causes NullPointerException when column name contains upper case char

• Type: Bug
• Status: Open
• Priority: Critical
• Resolution: Unresolved

Environment

ubuntu, Sqoop 1.4.4-cdh5.1.2, java 8

• Assignee: Unassigned
• Reporter: Shigeki Hirose
• Created: 19/Sep/14 04:54
• Updated: 27/Mar/15 12:52

Description

Sqoop command example:

sqoop import --connect "jdbc:mysql://127.0.0.1:3306/xxx" --username xxx --password xxx --table SampleTable --hcatalog-database xxx --create-hcatalog-table --hcatalog-storage-stanza 'stored as orc' --hcatalog-table sampletable

Call stack:

sqoop.Sqoop: Got exception running Sqoop: java.lang.NullPointerException
java.lang.NullPointerException
	at org.apache.sqoop.mapreduce.hcat.SqoopHCatUtilities.createHCatTable(SqoopHCatUtilities.java:491)
	at org.apache.sqoop.mapreduce.hcat.SqoopHCatUtilities.configureHCat(SqoopHCatUtilities.java:293)
	at org.apache.sqoop.mapreduce.hcat.SqoopHCatUtilities.configureImportOutputFormat(SqoopHCatUtilities.java:657)
	at org.apache.sqoop.mapreduce.ImportJobBase.configureOutputFormat(ImportJobBase.java:98)
	at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:240)
	at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:614)
	at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:118)
	at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:413)
	at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:506)
	at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
	at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
	at org.apache.sqoop.Sqoop.runTool(Sqoop.java:222)
	at org.apache.sqoop.Sqoop.runTool(Sqoop.java:231)
	at org.apache.sqoop.Sqoop.main(Sqoop.java:240)

This seems to be because source MySQL table contains a column name that has an upper case letter.

Sample table below. The column name, 'A', causes the exception.

DROP TABLE `SampleTable`;
CREATE TABLE `SampleTable` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `A` bigint(20) unsigned NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Once column name is changed to 'a', it works properly:

DROP TABLE `SampleTable`;
CREATE TABLE `SampleTable` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `a` bigint(20) unsigned NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

This is probably because LCKeyMap (and HCKeyMap) class in SqoopHCatUtilities.java line 160 - 177 are expecting HashMap to call put method for each element when putAll is invoked, which seem to have been the case in Java 6/7, but it doesn't behave that way in Java 8.

  /**
   * A Map using String as key type that ignores case of its key and stores the
   * key in lower case.
   */
  private static class LCKeyMap<V> extends HashMap<String, V> {
    private static final long serialVersionUID = -6751510232323094216L;
    @Override
    public V put(String key, V value) {
      return super.put(key.toLowerCase(), value);
    }
    @Override
    public V get(Object key) {
      return super.get(((String) key).toLowerCase());
    }
  }