java代码动态生成java的.class文件

目录

需要包： .......................................................................................................................................... 2

工具类POBuildUtil ......................................................................................................................... 2

工具类BuildUtil .............................................................................................................................. 6

工具类Assistant ............................................................................................................................... 8

RenderClass： ................................................................................................................................ 27

使用例子： .................................................................................................................................... 29

需要包：

1. apache-commons-lang-**.jar

2. asm-**.jar

工具类POBuildUtil

import ;

import tputStream;

import tion;

import or;

import ils;

import riter;

import Visitor;

import s;

public class POBuildUtil extends ClassLoader implements Opcodes {

public Class build(String clsname,String savepath,Collection

properties)

{

Class cls = null;

try

{

String classname = erClassName(clsname);

ClassWriter cw = new ClassWriter(false);

(V1_1, ACC_PUBLIC, classname, null,

"java/lang/Object", null);

MethodVisitor mw = ethod(ACC_PUBLIC, "",

"()V", null, null);

arInsn(ALOAD, 0);

ethodInsn(INVOKESPECIAL, "java/lang/Object",

"", "()V");

nsn(RETURN);

axs(1, 1);

nd();

BuildProperty property = null;

String propertytype = null;

String propertyname = null;;

Iterator iterator = or();

while (t())

{

property = (BuildProperty)();

propertytype =

erClassName(e());

propertyname = lize(e());

//n(propertyname);

ield(ACC_PRIVATE, e(),

"L"+propertytype+";", null, null).visitEnd();

mw = ethod(ACC_PUBLIC,

"get"+propertyname, "()L"+propertytype+";", null,

null);

ode();

arInsn(ALOAD, 0);

mw

.visitFieldInsn(GETFIELD, classname,

e(),

"L"+propertytype+";");

nsn(ARETURN);

axs(1, 1);

nd();

mw = ethod(ACC_PUBLIC,

"set"+propertyname, "(L"+propertytype+";)V",

null, null);

ode();

arInsn(ALOAD, 0);

arInsn(ALOAD, 1);

mw

.visitFieldInsn(PUTFIELD, classname,

e(),

"L"+propertytype+";");

axs(2, 2);

nsn(RETURN);

nd();

}

nd();

byte[] code = Array();

if (savepath!=null)

{

NewFile(savepath);

FileOutputStream fos =

FileOutputStream(savepath);

(code);

();

}

cls = Class(clsname, code, 0, );

new

}

}

}

return cls;

catch (Throwable e)

{

}

return cls;

tackTrace();

工具类BuildUtil

public class BuildUtil {

public static String transferClassName(Class

cls)

{

String clsname = e();

return e('.', '/');

}

public static String transferClassName(String

clsname)

{

return e('.', '/');

}

}

一． 工具类BuildProperty

public class BuildProperty {

private String name;

private String type;

public BuildProperty()

{

}

public BuildProperty(String name,String type)

{

= name;

= type;

}

public String getName() {

return name;

}

public void setName(String name) {

= name;

}

public String getType() {

return type;

}

public void setType(String type) {

= type;

}

}

工具类Assistant

import edReader;

import edWriter;

import ;

import putStream;

import tputStream;

import treamReader;

import StreamWriter;

import DateFormat;

import ar;

import tContext;

import rvletRequest;

import ;

public class Assistant {

private static final Logger log = ger();

public static String convertRequestParameter(String parameter)

throws Exception

{

}

public static String convertRequestParameter(String parameter,String

return convertRequestParameter(parameter,null);

format) throws Exception

{

}

public static boolean notEmpty(HttpServletRequest request,String

if (parameter!=null)

{

}

return parameter;

if (format==null)

format="utf-8";

parameter = (parameter,format);

key)

{

if (ameter(key)!=null &&

ameter(key).length()>0)

{

return true;

}

else

{

return false;

}

}

public static void writeFileContent(String

content ,ServletContext context) throws Exception

{

writeFileContent( getFullPath(url,context),content);

}

public static String HTMLEncode(String txt) {

if (txt!=null && ()>0)

{

txt=eAll("&","&");

txt=eAll("<","<");

txt=eAll(">",">");

url,String

}

}

txt=eAll(""",""");

txt=eAll("'","’");

return txt;

public static boolean existFile(String urlpath,ServletContext context)

{

}

public static void writeFileContent(String path,String content) throws

File file = new File(getFullPath(urlpath, context));

if (())

return true;

else

return false;

Exception

{

File file = new File(path);

if (!())

NewFile();

write= new OutputStreamWriter(new OutputStreamWriter

FileOutputStream(file),"GBK");

}

public static String getFileContent(String url,ServletContext context)

BufferedWriter writer=new BufferedWriter(write);

(content);

();

();

throws Exception

StringBuffer buf = new StringBuffer();

File file = new File(path);

if (())

{

InputStreamReader read = new InputStreamReader(new

{

}

public static String getFileContent(String path) throws Exception

{

String filepath = getFullPath(url,context);

return getFileContent(filepath);

FileInputStream(file),"GBK");

}

}

BufferedReader reader=new BufferedReader(read);

try

{

String content = ne();

while (content!=null)

{

}

(content);

content = ne();

}finally

{

}

if (reader!=null)

();

if (read!=null)

();

return ng();

//���ڼ�(����)

public static addTimeByDay( date,int days)

throws Exception

{

}

public static addTimeByMinutes( date,int

Calendar calendar=tance();

e(date);

(,()+days);

return e();

minutes) throws Exception

{

Calendar calendar=tance();

e(date);

(,()+minutes);

}

public static addTimeBySeconds( date,int

return e();

seconds) throws Exception

{

Calendar calendar=tance();

e(date);

(,()+seconds);

}

public static nowTime() throws Exception

{

SimpleDateFormat sdf = new

return e();

SimpleDateFormat("yyyy-MM-dd");

String datestr =

(tance().getTime());

}

public static nowFullTime() throws Exception

{

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd

return (datestr);

HH:mm:ss");

String datestr =

(tance().getTime());

}

return (datestr);

public static nowFullTime(String format) throws

Exception

{

SimpleDateFormat sdf = new SimpleDateFormat(format);

String datestr =

(tance().getTime());

}

public static String convertDateStrToString(String datestr,String

return (datestr);

format) throws Exception

{

String result = null;

SimpleDateFormat sdf = new SimpleDateFormat(format);

try

{

}

catch (Exception ex)

{

}

sdf = new SimpleDateFormat("yyyy-MM-dd");

result = ((datestr));

result = ((datestr));

}

return result;

public static String convertDateToString( date,String

format) throws Exception

{

}

public static formatDateStr(String datestr) throws

SimpleDateFormat sdf = new SimpleDateFormat(format);

return (date);

Exception

{

SimpleDateFormat sdf = new

SimpleDateFormat("yyyy-MM-dd");

}

public static formatDateStr(String datestr,String format)

return (datestr);

throws Exception

{

result = null;

SimpleDateFormat sdf = new SimpleDateFormat(format);

try

}

{

}

catch (Exception ex)

{

}

return result;

sdf = new SimpleDateFormat("yyyy-MM-dd");

result = (datestr);

result = (datestr);

public static formatFullDateStr(String datestr) throws

Exception

{

result = null;

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd

HH:mm:ss");

try

{

}

catch (Exception ex)

result = (datestr);

}

{

}

return result;

sdf = new SimpleDateFormat("yyyy-MM-dd");

result = (datestr);

public static String getFileName(String filepath)

{

}

public static void copy(ServletContext context,String form,String

filepath = e('/', '');

String filename = filepath;

if (dexOf('')>0)

{

}

return filename;

filename = ing(dexOf('')+1);

to ,boolean removeold) throws ption

copy(getFullPath(form,context),getFullPath(to,context),removeold);

{

}

//�ļ��������ƶ�����removeold �Ƿ�ɾ��ԭ�ļ�

public static void copy( String from, String to,boolean

removeold )throws ption

{

int BUFF_SIZE = 1024;

byte[] buffer = new byte[ BUFF_SIZE ];

tream in = null;

. OutputStream out = null;

try

{

in = new FileInputStream( from );

out = new FileOutputStream( to );

while ( true )

{

synchronized ( buffer )

{

int amountRead = ( buffer );

if ( amountRead == -1 )

{

break;

}

( buffer, 0, amountRead );

}

}

}

finally

{

if ( in != null )

{

();

}

if ( out != null )

{

();

}

}

n("..........................Copy Finish");

if (removeold)

{

file =new (from);

if (())

{

n("delete file:"+h());

}

}

}

();

public static String getUploadPath(String path)

{

}

//������·���õ����·��

public static String getFullPath(String url,ServletContext context)

{

url = e('', '/');

String path = lPath(url);

return e('/', '');

if (f("/")!=0)

{

}

if (dexOf("/")!=()-1)

{

}

return path;

path = path+"/";

path = "/"+path;

}

//������·��ɾ���ļ�

public static boolean deleteFile(String url,ServletContext context)

throws Exception

{

file =new (getFullPath(e('/',

''),context));

String filepath = h();

String ext = ing(dexOf(".")+1);

String minifilepath =

ing(0,dexOf("."))+"_mini."+ext;

minifile = new (minifilepath);

if (())

{

}

if (())

{

}

return false;

("delete file:"+h());

return ();

();

}

public static String createPathByDate(String url,ServletContext

context)

if (dexOf('')!=()-1 &&

{

String fullpath = getFullPath(url,context);

if (dexOf('')!=()-1)

Calendar nowtime = tance();

fullpath +=f(())+"";

SimpleDateFormat sdf = new SimpleDateFormat("MMdd");

fullpath+=(e())+"";

File file = new File(fullpath);

if (!())

();

fullpath +="";

dexOf('/')!=()-1)

url +="/";

url += f(())+"/";

url += (e())+"/";

}

return url;

public static boolean createPath(String path,ServletContext context)

throws Exception

ַ

public static String getContextUrl(String url,HttpServletRequest

{

}

//����һ����Ե�ַ�õ��ڵ�ǰ���������µ�һ����Ե�String fullpath = getFullPath(path,context);

File file = new File(fullpath);

boolean result= true;

if (!())

{

}

return result;

result =();

request,ServletContext context)

{

if (textPath()!=null &&

textPath().length()>0)

}

//���request �����Ƿ��ж�Ӧ��ֵ

public static Object getValue(HttpServletRequest request,String key)

{

}

public static void createNewFile(String savepath) throws

if (notEmpty(request, key))

return ameter(key);

{

}

return url;

if (f("/")!=0)

url = "/"+url;

url = textPath()+url;

else

return ribute(key);

ption

{

int pos = dexOf("");

}

}

String dir = ing(0,pos);

File directory =new File(dir);

if (!())

();

File file = new File(savepath);

if (())

NewFile();

RenderClass：

package on;

import ;

/*��ݿ�ӳ��������*/

public class RenderClass {

/*����*/

private String className;

/*��Ӧ����*/

private String tableName;

private String classPath;

/*����*/

private List properties;

public RenderClass()

{

properties = null;

}

public String getClassName() {

return className;

}

public void setClassName(String className) {

ame = className;

}

public String getTableName() {

return tableName;

}

public void setTableName(String tableName) {

ame = tableName;

}

public List getProperties() {

return properties;

}

public void setProperties(List properties) {

ties = properties;

}

public void setClassPath(String classPath) {

ath = classPath;

}

public String getClassPath() {

return classPath;

}

}

使用例子：

POBuildUtil util = new POBuildUtil();

(ssName(),ssPath()+""+leName()+".class",perties());

//在这里成功生成。class文件

注：以上代码均来自于网上资料。可直接复制即可使用