新建 文本文档.txt

主要介绍了JAVA的基本知识和异常处理的知识

C:\>jdb
Initializing jdb...
> ?
** command list **
run [class [args]]        -- start execution of application's main class

threads [threadgroup]     -- list threads
thread <thread id>        -- set default thread
suspend [thread id(s)]    -- suspend threads (default: all)
resume [thread id(s)]     -- resume threads (default: all)
where [thread id] | all   -- dump a thread's stack
wherei [thread id] | all  -- dump a thread's stack, with pc info
up [n frames]             -- move up a thread's stack
down [n frames]           -- move down a thread's stack
kill <thread> <expr>      -- kill a thread with the given exception object
interrupt <thread>        -- interrupt a thread

print <expr>              -- print value of expression
dump <expr>               -- print all object information
eval <expr>               -- evaluate expression (same as print)
set <lvalue> = <expr>     -- assign new value to field/variable/array element
locals                    -- print all local variables in current stack frame

classes                   -- list currently known classes
class <class id>          -- show details of named class
methods <class id>        -- list a class's methods
fields <class id>         -- list a class's fields

threadgroups              -- list threadgroups
threadgroup <name>        -- set current threadgroup

stop in <class id>.<method>[(argument_type,...)]
                          -- set a breakpoint in a method
stop at <class id>:<line> -- set a breakpoint at a line
clear <class id>.<method>[(argument_type,...)]
                          -- clear a breakpoint in a method
clear <class id>:<line>   -- clear a breakpoint at a line
clear                     -- list breakpoints
catch <class id>          -- break when specified exception thrown
ignore <class id>         -- cancel 'catch'  for the specified exception
watch [access|all] <class id>.<field name>
                          -- watch access/modifications to a field
unwatch [access|all] <class id>.<field name>
                          -- discontinue watching access/modifications to a fiel
d
trace methods [thread]    -- trace method entry and exit
untrace methods [thread]  -- stop tracing method entry and exit
step                      -- execute current line
step up                   -- execute until the current method returns to its cal
ler
stepi                     -- execute current instruction
next                      -- step one line (step OVER calls)
cont                      -- continue execution from breakpoint

list [line number|method] -- print source code
use (or sourcepath) [source file path]
                          -- display or change the source path
exclude [class id ... | "none"]
                          -- do not report step or method events for specified c
lasses
classpath                 -- print classpath info from target VM

monitor <command>         -- execute command each time the program stops
monitor                   -- list monitors
unmonitor <monitor#>      -- delete a monitor
read <filename>           -- read and execute a command file

lock <expr>               -- print lock info for an object
threadlocks [thread id]   -- print lock info for a thread

disablegc <expr>          -- prevent garbage collection of an object
enablegc <expr>           -- permit garbage collection of an object

!!                        -- repeat last command
<n> <command>             -- repeat command n times
help (or ?)               -- list commands
version                   -- print version information
exit (or quit)            -- exit debugger

<class id>: full class name with package qualifiers or a
pattern with a leading or trailing wildcard ('*').
<thread id>: thread number as reported in the 'threads' command
<expr>: a Java(tm) Programming Language expression.
Most common syntax is supported.

Startup commands can be placed in either "jdb.ini" or ".jdbrc"
in user.home or user.dir
>