fix mysql Connection URL Syntax

[xjr100419]

• Why do you submit this issue?

My orm framework mysql link does not specify the database: protocol//[hosts][/database][?properties] -> protocol//[hosts][?properties]

In code MysqlURLParser.fetchDatabaseHostsIndexRange() protected URLLocation fetchDatabaseHostsIndexRange() { int hostLabelStartIndex = url.indexOf("//"); int hostLabelEndIndex = url.indexOf("/", hostLabelStartIndex + 2); return new URLLocation(hostLabelStartIndex + 2, hostLabelEndIndex); }

then it report an error ERROR 2018-05-31 10:21:06 InstMethodsInter : class[class com.mysql.jdbc.Driver] after method[connect] intercept failure java.lang.StringIndexOutOfBoundsException: String index out of range: -14 at java.lang.String.substring(String.java:1967) at org.apache.skywalking.apm.plugin.jdbc.connectionurl.parser.MysqlURLParser.parse(MysqlURLParser.java:59) at org.apache.skywalking.apm.plugin.jdbc.connectionurl.parser.URLParser.parser(URLParser.java:48)

[xjr100419]

Connection URL Syntax: https://dev.mysql.com/doc/connector-j/8.0/en/connector-j-reference-jdbc-url-format.html

database The default database or catalog to open. If the database is not specified, the connection is made with no default database.

[wu-sheng]

So, you didn't set the database in your connection URL. Right?

If so, @ascrutae I think you should consider this as a special case. By the MySQL Connector official doc, it is allowed and legal.

[olds463]

@wu-sheng @ascrutae

FYI this issue still appears in latest release.

ERROR 2020-10-29 19:22:38:040 main StaticMethodsInter : class[class com.mysql.cj.jdbc.ConnectionImpl] after static method[getInstance] intercept failure:String index out of range: -14 java.lang.StringIndexOutOfBoundsException: String index out of range: -14 Caused by

ds.setUrl("jdbc:mysql://" + url + ":" + AWS_RDS_INSTANCE_PORT);

Adding in /dbName fixes issue.

Great software so far!