[雪峰磁针石博客]python与java对接工具Jython介绍
快速入门 下面我们使用jython来调用自定义jar包中的类。 编辑java文件：Beach.java public class Beach { private String name; private String city; public Beach(String name, String city){ this.name = name; this.city = city; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } } 编译成jar包： # javac Beach.java # echo Main-Class: Beach >manifest.txt # jar cvfm Craps.jar manifest.txt *.class 已添加清单 正在添加: Beach.class(输入 = 795) (输出 = 430)(压缩了 45%) 正在添加: Point.class(输入 = 708) (输出 = 445)(压缩了 37%) 添加Craps.jar到CLASSPATH，修改/etc/profile，修改CLASSPATH export CLASSPATH=.:$JAVA_HOME/jre/lib/rt.jar:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:/usr/local/jython/Craps.jar 使用. /etc/profile导入变量。然后使用jython调用java代码。 # ./jython Jython 2.7.0 (default:9987c746f838, Apr 29 2015, 02:25:11) [Java HotSpot(TM) 64-Bit Server VM (Oracle Corporation)] on java1.7.0_79 Type "help", "copyright", "credits" or "license" for more information. >>> import Beach >>> beach = Beach("Cocoa Beach","Cocoa Beach") >>> beach.getName() u'Cocoa Beach' >>> print beach.getName() Cocoa Beach >>> 基础 Linux安装： # java -jar jython-installer-2.7.0.jar # ./jython Jython 2.7.0 (default:9987c746f838, Apr 29 2015, 02:25:11) [Java HotSpot(TM) 64-Bit Server VM (Oracle Corporation)] on java1.7.0_79 Type "help", "copyright", "credits" or "license" for more information. >>> windows安装：双击jython-installer-2.7.0.jar, 执行jython.exe 变量定义： java int x = 0; jython： x = 0 x = 'Hello Jython' 是动态类型的。 保留字： and assert break class continue def del elif else except exec finally for from global or pass print raise return try while with yield 编码结构使用缩进。 函数名也可以作为函数的参数。 语句关键字： if-elif-else for while continue break try-except-finally assert def print del raise import 文件名和类名一样可以直接导入。 此部分参考资料： http://www.jython.org/jythonbook/en/1.0/JythonAndJavaIntegration.html http://www.skylit.com/javamethods/faqs/createjar.html 参考资料： http://www.jython.org/jythonbook/en/1.0/ 模块和包 查看命名空间 >>> dir() ['__builtins__', '__doc__', '__name__', '__package__'] Jython的导入不像java那样必须在头部。导入java以右边名优先，python以左边名优先。模块查找路径： >>> import sys >>> sys.path ['', '/usr/local/jython2.7.0/Lib', '__classpath__', '__pyclasspath__/', '/usr/local/jython2.7.0/Lib/site-packages'] >>> import sys >>> sys.path ['', '/usr/local/jython2.7.0/Lib', '__classpath__', '__pyclasspath__/', '/usr/local/jython2.7.0/Lib/site-packages'] >>> import sys >>> sys.path.append("/home/andrew/code/java/mysql-connector-java-5.1.39/mysql-connector-java-5.1.39-bin.jar") >>> import com.mysql *sys-package-mgr*: can't write cache file for '/home/andrew/code/java/mysql-connector-java-5.1.39/mysql-connector-java-5.1.39-bin.jar' *sys-package-mgr*: can't write index file >>> dir(com.mysql) ['__name__', 'fabric', 'jdbc'] >>> import java.util.zip >>> dir(java.util.zip) ['Adler32', 'CRC32', 'CheckedInputStream', 'CheckedOutputStream', 'Checksum', 'DataFormatException', 'Deflater', 'DeflaterInputStream', 'DeflaterOutputStream', 'GZIPInputStream', 'GZIPOutputStream', 'Inflater', 'InflaterInputStream', 'InflaterOutputStream', 'ZipEntry', 'ZipError', 'ZipException', 'ZipFile', 'ZipInputStream', 'ZipOutputStream', '__name__'] >>> dir(java.util.zip.ZipInputStream) ['__class__', '__copy__', '__deepcopy__', '__delattr__', '__doc__', '__ensure_finalizer__', '__eq__', '__format__', '__getattribute__', '__hash__', '__init__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__str__', '__subclasshook__', '__unicode__', 'available', 'class', 'close', 'closeEntry', 'equals', 'getClass', 'getNextEntry', 'hashCode', 'mark', 'markSupported', 'nextEntry', 'notify', 'notifyAll', 'read', 'reset', 'skip', 'toString', 'wait'] Jython 查找Jar和类的方法： python.packages.paths python.packages.directories java.class.path java.ext.dirs python.cachedir.skip pycimport把python字节码转换成java字节码。Jython导入java包可能有多个包合并。 >>> import sys >>> sys.path_hooks [<type 'org.python.core.JavaImporter'>, <type 'zipimport.zipimporter'>, <type 'ClasspathPyImporter'>] import pycimport 数据类型 Jython特定的collection，多用于给java传递数据。 # Import and use a Java ArrayList >>> import java.util.ArrayList as ArrayList >>> arr = ArrayList() # Add method will add an element to the list and return a boolean to signify successsful addition >>> arr.add(1) True >>> arr.add(2) True >>> print arr [1, 2] 比较老的Jarray，不推荐使用，不过可以创建空数组： 类型： Character Java Equivalent z boolean b byte c char d Double f Float h Short i Int l Long >>> my_seq = (1,2,3,4,5) >>> from jarray import array >>> array(my_seq,'i') array('i', [1, 2, 3, 4, 5]) >>> myStr = "Hello Jython" >>> array(myStr,'c') array('c', 'Hello Jython') >>> arr = zeros(10,'z') >>> arr array('z', [False, False, False, False, False, False, False, False, False, False]) >>> arr2 = zeros(6, 'i') >>> arr2 array('i', [0, 0, 0, 0, 0, 0]) 求素数 `>>> ``nums = range(2, 50) ` `>>> ``for i in range(2, 8): ` `... `` nums = filter(lambda x: x == i or x % i, nums)` `... ` `>>> ``print nums` 读取输入： <pre># Obtain a value from the command line and store it into a variable >>> import sys >>> fav_team = sys.stdin.readline() Cubs >>> sys.stdout.write("My favorite team is: %s" % fav_team) My favorite team is: Cubs</pre> 函数 协程： **def** search_file(filename): **print** 'Searching file *%s*' % (filename) my_file = open(filename, 'r') file_content = my_file.read() my_file.close() **while** True: search_text = (**yield**) search_result = file_content.count(search_text) **print** 'Number of matches: *%d*' % (search_result)</pre> Jython脚本编程基础 os.chdir不会改变jvm的启动目录。 >>> import os >>> os.getcwd() '/Users/frank/Desktop/frank/hg/jythonbook~jython-book/src/chapter8' >>> from java.io import File >>> f = File(".") >>> for x in f.list(): ... print x ... args.py search.py >>> os.chdir("/Users/frank") >>> os.getcwd() '/Users/frank' >>> os.listdir(".") ['Desktop', 'Documents', 'Downloads', 'Dropbox', 'Library', 'Movies', 'Music', 'Pictures', 'Public', 'Sites'] >>> g = File(".") >>> for x in g.list(): ... print x ... args.py search.py 编译代码 !/usr/local/jython2.7.0/bin/jython from javax.tools import (ForwardingJavaFileManager, ToolProvider, DiagnosticCollector,)names = ["/home/andrew/code/python/jythonbook/src/chapter8/HelloWorld.java"]compiler = ToolProvider.getSystemJavaCompiler()diagnostics = DiagnosticCollector()manager = compiler.getStandardFileManager(diagnostics, None, None)units = manager.getJavaFileObjectsFromStrings(names)comp_task = compiler.getTask(None, manager, diagnostics, None, None, units)success = comp_task.call()manager.close() import osimport sysimport glob from javax.tools import (forwardingjavafilemanager, toolprovider, diagnosticcollector,) tasks = {} def task(func): tasks[func.func_name] = func @taskdef clean(): files = glob.glob("\*.class") **for** file **in** files: os.unlink(file) @taskdef compile(): files = glob.glob("\*.java") _log("compiling *%s*" % files) **if** **not** _compile(files): quit() _log("compiled") def _log(message): **if** options.verbose: **print** message def _compile(names): compiler = toolprovider.getsystemjavacompiler() diagnostics = diagnosticcollector() manager = compiler.getstandardfilemanager(diagnostics, none, none) units = manager.getjavafileobjectsfromstrings(names) comp_task = compiler.gettask(none, manager, diagnostics, none, none, units) success = comp_task.call() manager.close() **return** success if name == '__main__': **from** **optparse** **import** optionparser parser = optionparser() parser.add_option("-q", "--quiet", action="store_false", dest="verbose", default=true, help="don't print out task messages.") parser.add_option("-p", "--projecthelp", action="store_true", dest="projecthelp", help="print out list of tasks.") (options, args) = parser.parse_args() **if** options.projecthelp: **for** task **in** tasks: **print** task sys.exit(0) **if** len(args) < 1: **print** "usage: jython builder.py [options] task" sys.exit(1) **try**: current = tasks[args[0]] **except** KeyError: **print** "task *%s* not defined." % args[0] sys.exit(1) current()</pre> public class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World"); } } [frank@pacman chapter8]$ jython builder.py --helpUsage: builder.py [options] Options: -h, --help show this help message and exit -q, --quiet Don't print out task messages. -p, --projecthelp Print out list of tasks. [frank@pacman chapter8]$ jython builder.py --projecthelpcompileclean[frank@pacman chapter8]$ jython builder.py compilecompiling ['HelloWorld.java']compiled[frank@pacman chapter8]$ lsHelloWorld.java HelloWorld.class builder.py[frank@pacman chapter8]$ jython builder.py clean[frank@pacman chapter8]$ lsHelloWorld.java builder.py[frank@pacman chapter8]$ jython builder.py --quiet compile[frank@pacman chapter8]$ lsHelloWorld.class HelloWorld.java builder.py[frank@pacman chapter8]$
