There are two ways to specify how GET parameters are interpreted:
Set the URIEncoding attribute on the <Connector> element in server.xml to something specific (e.g. URIEncoding="UTF-8").
Set the useBodyEncodingForURI attribute on the <Connector> element in server.xml to true. This will cause the Connector to use the request body's encoding for GET parameters.
Creating BufferedReader from Files.newBufferedReader
when running the application it may throw the following exception:
java.nio.charset.MalformedInputException: Input length = 1
new BufferedReader(new InputStreamReader(new FileInputStream("a.txt"),"utf-8"));
The different is that, the former uses CharsetDecoder default action.
The default action for malformed-input and unmappable-character errors is to report them.
while the latter uses the REPLACE action.
By default, the virtual machine grows or shrinks the heap at each collection to try to keep the proportion of free space to live objects at each collection within a specific range. This target range is set as a percentage by the parameters -XX:MinHeapFreeRatio= and -XX:MaxHeapFreeRatio=, and the total size is bounded below by -Xms and above by -Xmx .
slabtop command (part of the package procps) shows top memory objects used by the kernel.
dstat can help you figure out what is happening. dstat -cdnpmgs --top-bio --top-cpu --top-mem
Also have a look at smem ("smem -kt"), it can show you nicely what is in your swap.
From the community documentation:
hibernate.hbm2ddl.auto Automatically validates or exports schema DDL to the database when the SessionFactory is created. With create-drop, the database schema will be dropped when the SessionFactory is closed explicitly.
e.g. validate | update | create | create-drop
So the list of possible options are,
validate: validate the schema, makes no changes to the database.
update: update the schema.
create: creates the schema, destroying previous data.
create-drop: drop the schema at the end of the session.