jdb(1) Basic Tools jdb(1) (NAME) jdb - . (SYNOPSIS) jdb [options] [classname] [arguments] options . <<>> . classname . arguments main() . (DESCRIPTION) (JDB) . jdb JDB . jdb (JDBA) (JVM) . (JDBA) http://docs.oracle.com/javase/8/docs/technotes/guides/jpda/index.html . JDB (START A JDB SESSION) JDB . JDB JVM . jdb java . MyClass JDB : jdb MyClass jdb JVM JVM . jdb JVM . JVM jdb . (in-process) . java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n MyClass jdb JVM : jdb -attach 8000 MyClass jdb jdb JVM JVM . JVM jdb . . JDB (BASIC JDB COMMANDS) jdb . JDB -help . help or ? help ? . run JDB (breakpoints) run . run jdb JVM . cont (exception) . print (primitive) . . . dump . : javac -g . print : print MyClass.myStaticField print myObj.myInstanceField print i + j + k (i, j, k are primities and either fields or local variables) print myObj.myMethod() (if myMethod returns a non-null) print new java.lang.String("Hello").length() dump dump print . dump . (static) (instance) . dump print . threads (threads) . (index) . 4 java.lang.Thread main . 4. (java.lang.Thread)0x1 main running thread . jdb . threads . where where (stack) (dump) . whereall . wherethreadindex . suspend print dump . up down (stack frame) . (BREAKPOINTS) JDB : o stop at MyClass:22 22 MyClass . o stop in java.lang.String.length java.lang.String.length . o stop in MyClass. (static initialization) MyClass . (overload) MyClass.myMethod(int,java.lang.String) MyClass.myMethod(). clear : clear MyClass:45. clear stop . cont . (STEPPING) step . next . (EXCEPTIONS) catch JVM (exception trace) . JDB JDB . jdb . catch : catch java.io.FileNotFoundException catchmypackage.BigTroubleException. . ignore catch . ignore JVM . (OPTIONS) java jdb jdb java -D -classpath -X. jdb . JVM . (JPDA) http://docs.oracle.com/javase/8/docs/technotes/guides/jpda/index.html . -help . -sourcepath dir1:dir2: . . . . (.) . -attach address JVM . -listen address JVM . -launch JDB . -launch run . . cont . -listconnectors JVM . -connect connector-name:name1=value1 JVM . -dbgtrace [flags] jdb . -tclient Java HotSpot VM client . -tserver Java HotSpot VM server . -Joption option JVM option . -J-Xms48m 48 . java(1) . (OPTIONS FORWARDED TO THE DEBUGGER PROCESS) -v -verbose[:class|gc|jni] (verbose) . -Dname=value (system property) . -classpath dir (:) . -Xoption JVM . (SEE ALSO) o javac(1) o java(1) o javap(1) JDK 8 21 November 2013 jdb(1)