ECJ(1) General Commands Manual ECJ(1)
NAME
ecj - manual page for eclipse JDT Compiler
SYNOPSIS
ecj <options> <source files>
DESCRIPTION
The JDT Compiler (jdtc) is a command version of Java compiler for eclipse. ecj has basic java compiler options like SUN's javac.
Note: this manual page is out of date; please call the compiler with -help for the current documentation.
OPTIONS
-help display a help message
-version compiler version number
-classpath <dir 1>;<dir 2>;...;<dir P>
-d <dir> destination directory (if omitted no package directory structure is created)
-d none
no classfile is generated
-1.3 set compliance level to 1.3
-1.4 set compliance level to 1.4 (default)
-1.5 set compliance level to 1.5
-1.6 set compliance level to 1.6
-1.7 set compliance level to 1.7
-source <ver> assertions toggle (1.3 or 1.4, default is 1.3 in -1.3 mode and 1.4 in -1.4 mode)
-target <ver> classfile target setting
-nowarn no warning (equivalent to '-warn:none')
-warn: <level> set warning level (e.g. '-warn:unusedLocals,deprecation')
constructorName
warn method with constructor name
packageDefaultMethod
warn attempt to override package-default method
deprecation
warn usage of deprecated type or member
maskedCatchBlocks
warn hidden catch block
unusedLocals
warn on unused local variable (never read)
unusedArguments
warn on unused method argument (never read)
unusedImports
warn on unused imports
syntheticAccess
warn when performing synthetic access for innerclass
assertIdentifier
warn occurrence of 'assert' used as identifier
-deprecation equivalent to -warn:deprecation. -g[:<level>] debug attributes level
-g all debug info ('-g:lines,vars,source')
-g:none
no debug info
-g:[lines,vars,source]
selective debug info
-preserveAllLocals code gen preserve all local variables (for debug purpose)
-noImportError no errors for unresolved imports
-encoding specify default source encoding format (custom encoding can also be specifed on a per file basis by suffixing each
input source file/folder name with '[encoding]')
-log <filename> specify a log file
-proceedOnError keep compiling when error, dumping class files with problem methods
-verbose print accessedprocessed compilation units
-referenceInfo compute reference info
-progress show progress (only in -log mode)
-time display speed information
-noExit do not call System.exit(n) at end of compilation (n=0 if no error)
-repeat <n> repeat compilation process <n> times (perf analysis)
AUTHOR
This manual page was written by Takshi Okamoto and Jan Schulz <debian@katzien.de>.
October 2002 ECJ(1)
Check Out this Related Man Page
ajc(1) General Commands Manual ajc(1)
NAME
ajc -- compiler and bytecode weaver for the AspectJ and Java languages
SYNOPSIS
ajc [Options] [file... | @file... | -argfile file... ]
Description
The ajc command compiles and weaves AspectJ and Java source and .class files, producing .class files compliant with any Java VM (1.1 or
later). It combines compilation and bytecode weaving and supports incremental builds; you can also weave bytecode at run-time using "" >.
The arguments after the options specify the source file(s) to compile. To specify source classes, use -inpath (below). Files may be
listed directly on the command line or in a file. The -argfile file and @file forms are equivalent, and are interpreted as meaning all the
arguments listed in the specified file.
Note: You must explicitly pass ajc all necessary sources. Be sure to include the source not only for the aspects or pointcuts but also for
any affected types. Specifying all sources is necessary because, unlike javac, ajc does not search the sourcepath for classes. (For a
discussion of what affected types might be required, see The AspectJ Programming Guide, Implementation Appendix ../progguide/implementa-
tion.html) .
To specify sources, you can list source files as arguments or use the options -sourceroots or -inpath. If there are multiple sources for
any type, the result is undefined since ajc has no way to determine which source is correct. (This happens most often when users include
the destination directory on the inpath and rebuild.)
Options
-injars JarList
deprecated: since 1.2, use -inpath, which also takes directories.
-inpath Path
Accept as source bytecode any .class files in the The output will include these classes, possibly as woven with any applicable
aspects. Path is a single argument containing a list of paths to zip files or directories, delimited by the platform-specific
path delimiter.
-aspectpath Path
Weave binary aspects from jar files and directories on path into all sources. The aspects should have been output by the same
version of the compiler. When running the output classes, the run classpath should contain all aspectpath entries. Path, like
classpath, is a single argument containing a list of paths to jar files, delimited by the platform- specific classpath delimiter.
-argfile File
The file contains a line-delimited list of arguments. Each line in the file should contain one option, filename, or argument
string (e.g., a classpath or inpath). Arguments read from the file are inserted into the argument list for the command. Rela-
tive paths in the file are calculated from the directory containing the file (not the current working directory). Comments, as
in Java, start with // and extend to the end of the line. Options specified in argument files may override rather than extending
existing option values, so avoid specifying options like -classpath in argument files unlike the argument file is the
only build specification. The form @file is the same as specifying -argfile file.
-outjar output.jar
Put output classes in zip file output.jar.
-outxml Generate aop.xml file for load-time weaving with default name.
-outxmlfile custom/aop.xml
Generate aop.xml file for load-time weaving with custom name.
-incremental
Run the compiler continuously. After the initial compilation, the compiler will wait to recompile until it reads a newline from
the standard input, and will quit when it reads a 'q'. It will only recompile necessary components, so a recompile should be
much faster than doing a second compile. This requires -sourceroots.
-sourceroots DirPaths
Find and build all .java or .aj source files under any directory listed in DirPaths. DirPaths, like classpath, is a single argu-
ment containing a list of paths to directories, delimited by the platform- specific classpath delimiter. Required by -incremen-
tal.
-crossrefs
Generate a build .ajsym file into the output directory. Used for viewing crosscutting references by tools like the AspectJ
Browser.
-emacssym Generate .ajesym symbol files for emacs support (deprecated).
-Xlint Same as -Xlint:warning (enabled by default)
-Xlint:{level}
Set default level for messages about potential programming mistakes in crosscutting code. {level} may be ignore, warning, or
error. This overrides entries in org/aspectj/weaver/XlintDefault.properties from aspectjtools.jar, but does not override levels
set using the -Xlintfile option.
-Xlintfile PropertyFile
Specify properties file to set levels for specific crosscutting messages. PropertyFile is a path to a Java .properties file that
takes the same property names and values as org/aspectj/weaver/XlintDefault.properties from aspectjtools.jar, which it also over-
rides.
-help Emit information on compiler options and usage
-version Emit the version of the AspectJ compiler
-classpath Path
Specify where to find user class files. Path is a single argument containing a list of paths to zip files or directories, delim-
ited by the platform-specific path delimiter.
-bootclasspath Path
Override location of VM's bootclasspath for purposes of evaluating types when compiling. Path is a single argument containing a
list of paths to zip files or directories, delimited by the platform-specific path delimiter.
-extdirs Path
Override location of VM's extension directories for purposes of evaluating types when compiling. Path is a single argument con-
taining a list of paths to directories, delimited by the platform-specific path delimiter.
-d Directory
Specify where to place generated .class files. If not specified, Directory defaults to the current working dir.
-target [1.1 to 1.5]
Specify classfile target setting (1.1 to 1.5, default is 1.2)
-1.3 Set compliance level to 1.3 This implies -source 1.3 and -target 1.1.
-1.4 Set compliance level to 1.4 (default) This implies -source 1.4 and -target 1.2.
-1.5 Set compliance level to 1.5. This implies -source 1.5 and -target 1.5.
-source [1.3|1.4|1.5]
Toggle assertions (1.3, 1.4, or 1.5 - default is 1.4). When using -source 1.3, an assert() statement valid under Java 1.4 will
result in a compiler error. When using -source 1.4, treat assert as a keyword and implement assertions according to the 1.4 lan-
guage spec. When using -source 1.5, Java 5 language features are permitted.
-nowarn Emit no warnings (equivalent to '-warn:none') This does not suppress messages generated by declare warning or Xlint.
-warn: items
Emit warnings for any instances of the comma-delimited list of questionable code (eg '-warn:unusedLocals,deprecation'):
constructorName method with constructor name
packageDefaultMethod attempt to override package-default method
deprecation usage of deprecated type or member
maskedCatchBlocks hidden catch block
unusedLocals local variable never read
unusedArguments method argument never read
unusedImports import statement not used by code in file
none suppress all compiler warnings
-warn:none does not suppress messages generated by declare warning or Xlint.
-deprecation
Same as -warn:deprecation
-noImportError
Emit no errors for unresolved imports
-proceedOnError
Keep compiling after error, dumping class files with problem methods
-g:[lines,vars,source]
debug attributes level, that may take three forms:
-g all debug info ('-g:lines,vars,source')
-g:none no debug info
-g:{items} debug info for any/all of [lines, vars, source], e.g.,
-g:lines,source
-preserveAllLocals
Preserve all local variables during code generation (to facilitate debugging).
-referenceInfo
Compute reference information.
-encoding format
Specify default source encoding format. Specify custom encoding on a per file basis by suffixing each input source file/folder
name with '[encoding]'.
-verbose Emit messages about accessed/processed compilation units
-showWeaveInfo
Emit messages about weaving
-log file Specify a log file for compiler messages.
-progress Show progress (requires -log mode).
-time Display speed information.
-noExit Do not call System.exit(n) at end of compilation (n=0 if no error)
-repeat N Repeat compilation process N times (typically to do performance analysis).
-XterminateAfterCompilation
Causes compiler to terminate before weaving
-XaddSerialVersionUID
Causes the compiler to calculate and add the SerialVersionUID field to any type implementing Serializable that is affected by an
aspect. The field is calculated based on the class before weaving has taken place.
-Xreweavable[:compress]
(Experimental - deprecated as now default) Runs weaver in reweavable mode which causes it to create woven classes that can be
rewoven, subject to the restriction that on attempting a reweave all the types that advised the woven type must be accessible.
-XnoInline
(Experimental) do not inline around advice
-XincrementalFile file
(Experimental) This works like incremental mode, but using a file rather than standard input to control the compiler. It will
recompile each time file is changed and and halt when file is deleted.
-XserializableAspects
(Experimental) Normally it is an error to declare aspects Serializable. This option removes that restriction.
-XnotReweavable
(Experimental) Create class files that can't be subsequently rewoven by AspectJ.
-Xajruntimelevel:1.2, ajruntimelevel:1.5
(Experimental) Allows code to be generated that targets a 1.2 or a 1.5 level AspectJ runtime (default 1.5)
File names
ajc accepts source files with either the .java extension or the .aj extension. We normally use .java for all of our files in an
AspectJ system -- files that contain aspects as well as files that contain classes. However, if you have a need to mechanically distin-
guish files that use AspectJ's additional functionality from those that are pure Java we recommend using the .aj extension for those files.
We'd like to discourage other means of mechanical distinction such as naming conventions or sub-packages in favor of the .aj extension.
o Filename conventions are hard to enforce and lead to awkward names for your aspects. Instead of TracingAspect.java we recommend
using Tracing.aj (or just Tracing.java) instead.
o Sub-packages move aspects out of their natural place in a system and can create an artificial need for privileged aspects. Instead
of adding a sub-package like aspects we recommend using the .aj extension and including these files in your existing packages
instead.
Compatibility
AspectJ is a compatible extension to the Java programming language. The AspectJ compiler adheres to the The Java Language Specfication,
Second Edition (BOOK) http://java.sun.com/docs/books/jls/index.html and to the The Java Virtual Machine Specification, Second Edition
(BOOK) http://java.sun.com/docs/books/vmspec/index.html and runs on any Java 2 compatible platform. The code it generates runs on any Java
1.1 or later compatible platform. For more information on compatibility with Java and with previous releases of AspectJ, see "" >.
Examples
A simple example
Compile two files:
ajc HelloWorld.java Trace.java
An example using -argfile/@
To avoid specifying file names on the command line, list source files in a line-delimited text argfile. Source file paths may be absolute
or relative to the argfile, and may include other argfiles by @-reference. The following file sources.lst contains absolute and
relative files and @-references:
Gui.java
/home/user/src/Library.java
data/Repository.java
data/Access.java
@../../common/common.lst
@/home/user/src/lib.lst
view/body/ArrayView.java
Compile the files using either the -argfile or @ form:
ajc -argfile sources.lst
ajc @sources.lst
Argfiles are also supported by jikes and javac, so you can use the files in hybrid builds. However, the support varies:
o Only ajc accepts command-line options
o Jikes and Javac do not accept internal @argfile references.
o Jikes and Javac only accept the @file form on the command line.
An example using -inpath and -aspectpath
Bytecode weaving using -inpath: AspectJ 1.2 supports weaving .class files in input zip/jar files and directories. Using input jars is like
compiling the corresponding source files, and all binaries are emitted to output. Although Java-compliant compilers may differ in their
output, ajc should take as input any class files produced by javac, jikes, eclipse, and, of course, ajc. Aspects included in -inpath will
be woven into like other .class files, and they will affect other types as usual.
Aspect libraries using -aspectpath: AspectJ 1.1 supports weaving from read-only libraries containing aspects. Like input jars, they affect
all input; unlike input jars, they themselves are not affected or emitted as output. Sources compiled with aspect libraries must be run
with the same aspect libraries on their classpath.
The following example builds the tracing example in a command-line environment; it creates a read-only aspect library, compiles some
classes for use as input bytecode, and compiles the classes and other sources with the aspect library.
The tracing example is in the AspectJ distribution ({aspectj}/doc/examples/tracing). This uses the following files:
aspectj1.1/
bin/
ajc
lib/
aspectjrt.jar
examples/
tracing/
Circle.java
ExampleMain.java
lib/
AbstractTrace.java
TraceMyClasses.java
notrace.lst
Square.java
tracelib.lst
tracev3.lst
TwoDShape.java
version3/
Trace.java
TraceMyClasses.java
Below, the path separator is taken as ";", but file separators are "/". All commands are on one line. Adjust paths and commands to your
environment as needed.
Setup the path, classpath, and current directory:
cd examples
export ajrt=../lib/aspectjrt.jar
export CLASSPATH="$ajrt"
export PATH="../bin:$PATH"
Build a read-only tracing library:
ajc -argfile tracing/tracelib.lst -outjar tracelib.jar
Build the application with tracing in one step:
ajc -aspectpath tracelib.jar -argfile tracing/notrace.lst -outjar tracedapp.jar
Run the application with tracing:
java -classpath "$ajrt;tracedapp.jar;tracelib.jar" tracing.ExampleMain
Build the application with tracing from binaries in two steps:
o (a) Build the application classes (using javac for demonstration's sake):
mkdir classes
javac -d classes tracing/*.java
jar cfM app.jar -C classes .
o (b) Build the application with tracing:
ajc -inpath app.jar -aspectpath tracelib.jar -outjar tracedapp.jar
Run the application with tracing (same as above):
java -classpath "$ajrt;tracedapp.jar;tracelib.jar" tracing.ExampleMain
Run the application without tracing:
java -classpath "app.jar" tracing.ExampleMain
The AspectJ compiler API
The AspectJ compiler is implemented completely in Java and can be called as a Java class. The only interface that should be considered
public are the public methods in org.aspectj.tools.ajc.Main. E.g., main(String[] args) takes the the standard ajc command line arguments.
This means that an alternative way to run the compiler is
java org.aspectj.tools.ajc.Main [option...] [file...]
To access compiler messages programmatically, use the methods setHolder(IMessageHolder holder) and/or run(String[] args, IMessageHolder
holder). ajc reports each message to the holder using IMessageHolder.handleMessage(..). If you just want to collect the messages, use
MessageHandler as your IMessageHolder. For example, compile and run the following with aspectjtools.jar on the classpath:
import org.aspectj.bridge.*;
import org.aspectj.tools.ajc.Main;
import java.util.Arrays;
public class WrapAjc {
public static void main(String[] args) {
Main compiler = new Main();
MessageHandler m = new MessageHandler();
compiler.run(args, m);
IMessage[] ms = m.getMessages(null, true);
System.out.println("messages: " + Arrays.asList(ms));
}
}
Stack Traces and the SourceFile attribute
Unlike traditional java compilers, the AspectJ compiler may in certain cases generate classfiles from multiple source files. Unfortu-
nately, the original Java class file format does not support multiple SourceFile attributes. In order to make sure all source file infor-
mation is available, the AspectJ compiler may in some cases encode multiple filenames in the SourceFile attribute. When the Java VM gener-
ates stack traces, it uses this attribute to specify the source file.
(The AspectJ 1.0 compiler also supports the .class file extensions of JSR-45. These permit compliant debuggers (such as jdb in Java 1.4.1)
to identify the right file and line even given many source files for a single class. JSR-45 support is planned for ajc in AspectJ 1.1, but
is not in the initial release. To get fully debuggable .class files, use the -XnoInline option.)
Probably the only time you may see this format is when you view stack traces, where you may encounter traces of the format
java.lang.NullPointerException
at Main.new$constructor_call37(Main.java;SynchAspect.java[1k]:1030)
where instead of the usual
File:LineNumber
format, you see
File0;File1[Number1];File2[Number2] ... :LineNumber
In this case, LineNumber is the usual offset in lines plus the "start line" of the actual source file. That means you use LineNumber both
to identify the source file and to find the line at issue. The number in [brackets] after each file tells you the virtual "start line" for
that file (the first file has a start of 0).
In our example from the null pointer exception trace, the virtual start line is 1030. Since the file SynchAspect.java "starts" at line
1000 [1k], the LineNumber points to line 30 of SynchAspect.java.
So, when faced with such stack traces, the way to find the actual source location is to look through the list of "start line" numbers to
find the one just under the shown line number. That is the file where the source location can actually be found. Then, subtract that
"start line" from the shown line number to find the actual line number within that file.
In a class file that comes from only a single source file, the AspectJ compiler generates SourceFile attributes consistent with traditional
Java compilers.
ajc(1)