Oracle sqlplus command line tools does not support command line editing out-of-the-box. But on Linux there's a handy utility that enables command line editing with any command line tool: rlwrap - readline wrapper. Install rlwrap: $ sudo apt-get install rlwrap Create a keywords file .sql.dict (optional, but convenient): false null true access add as asc begin by chec... It would be nice to add the tables names also. Create an alias for sqlplus (put it in .bashrc ): alias sqlplus='rlwrap -f $HOME/.sql.dict sqlplus'

Use the expand command to extract files from a .cab file: expand [-r] source [destination] [-d source.cab ... Option Description [-r] Renames expanded files. [destination] Specifies where files are to be expanded. If source is multiple files and -r is not specified, destination must be a directory. destination can consist of a drive letter and colon, a directory name, a file name, or a combination of any of these. [-d source.cab] Displays a list of files in the source location. Does not expand or extract the files. [-f:files] Specifies the files in a cabinet (.cab) file that you intend to expand. You can use wildcards (* and ?). source.cab Specifies the files to expand. source can consist of a drive letter and colon, a directory...

Resource files under the src/main/resources directory are copied verbatim to the target/classes directory during build. But resources can be filtered by turning on filtering in pom.xml : <build> <resources> <resource> ... When filtering is turned on, constructs like ${...} are replaced with actual values if they are defined. For example, create a file test.properties : project.stage=${project.stage} The build command " mvn package " simply copies test.properties to target/classes/ . But if you build with: mvn -Dproject.stage=dev package the contents of target/classes/test.properties becomes: project.stage=dev Sometimes you want different resource definitions for different environments, e.g., dev vs. prod. You can achieve that by defining profiles in pom.xml : <profiles> <profile> <id>dev</id> ... In the above, dev is the default profile, prod is defined but not active unless...

I got this error while building an APK: [apply] [apply] UNEXPECTED TOP-LEVEL ERROR... Apparently the dx tool was running out of memory. The dx script (shell or bat) provides options to pass in Java options, but it's a lot easier just to bump up the default in dx : # By default, give dx a max heap size of 1 gig. Th... Here, I changed the default 1024M to 1624M and resolved the problem.

To list all installed packages: # pm list packages To list all disabled packages: # pm list packages -d pm help: # pm usage: pm [list|path|install|uninstall] ...

Some javap usage examples. Start from HelloWorld.java : @Deprecated public class HelloWorld { pu... javap -c HelloWorld outputs: Compiled from "HelloWorld.java" public class He... javap -v HelloWorld outputs ( -v for verbose mode): Compiled from "HelloWorld.java" public class He... The output consists of: " Compiled from... " header Class attributes. For the HelloWorld example, there are two: SourceFile and Deprecated . Minor and major class file version Constant pool Disassembled code LineNumberTable for debugging purposes. javap by default only prints package/protected/public members. To display all members including private, use the -p switch. javap -v -p HelloWorld

Assign IP adrress and network mask: sudo ifconfig eth0 192.168.183.5 netmask 255.255.2... Add default gateway: sudo route add default gw 192.168.183.2 Add name server: " sudo vi /etc/resolv.conf " and add: nameserver 192.168.183.2

The bash environment variable PROMPT_COMMAND contains a regular bash command that is executed just before the command prompt is displayed. For example: $ export PROMPT_COMMAND=a bash: a: command not ... The command a is not valid so you get the error message every time you hit enter. Echo something before $PS1 : $ export PROMPT_COMMAND='echo -n Hi!' Hi!$ ... PROMPT_COMMAND is regularly used to change the xterm window title. You may find this in /etc/bashrc : case $TERM in xterm*) if [ -...

To sign an Android APK from command line: Sign the APK with jarsigner (using default keystore, android-root is the alias of the signing key): $ jarsigner -signedjar HelloWorld-new.apk HelloWor... Verify signature (optional) $ jarsigner -verify -verbose -certs HelloWorld-new... Align the APK (must use -v 4 option): $ ~/android-sdk-linux_86/tools/zipalign -v 4 Hello...

With StringBuffer/StringBuilder: public class ReverseString { private static... Without StringBuffer/StringBuilder: public class ReverseString { private static...