@SuppressWarnings抑制警告

@SuppressWarnings(“XXXX”) 来抑制编译时的警告信息。参数如下：

关键字	用途
all	to suppress all warnings
boxing	to suppress warnings relative to boxing/unboxing operations
cast	to suppress warnings relative to cast operations
dep-ann	to suppress warnings relative to deprecated annotation
deprecation	to suppress warnings relative to deprecation
fallthrough	to suppress warnings relative to missing breaks in switch statements
finally	to suppress warnings relative to finally block that don’t return
hiding	to suppress warnings relative to locals that hide variable
incomplete-switch	to suppress warnings relative to missing entries in a switch statement (enum case)
nls	to suppress warnings relative to non-nls string literals
null	to suppress warnings relative to null analysis
rawtypes	to suppress warnings relative to un-specific types when using generics on class params
restriction	to suppress warnings relative to usage of discouraged or forbidden references
serial	to suppress warnings relative to missing serialVersionUID field for a serializable class
static-access	o suppress warnings relative to incorrect static access
synthetic-access	to suppress warnings relative to unoptimized access from inner classes
unchecked	to suppress warnings relative to unchecked operations
unqualified-field-access	to suppress warnings relative to field access unqualified
unused	to suppress warnings relative to unused code