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
Files.newBufferedReader(Paths.get("a.txt"), StandardCharsets.UTF_8);
when running the application it may throw the following exception:
java.nio.charset.MalformedInputException: Input length = 1
But
new BufferedReader(new InputStreamReader(new FileInputStream("a.txt"),"utf-8"));
works well.
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.
cs.newDecoder().onMalformedInput(CodingErrorAction.REPLACE).onUnmappableCharacter(CodingErrorAction.REPLACE)
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.