java-code-example/Dynamic_Load_Class/Main.java at master · cherkavi/java-code-example · GitHub

History

executable file

250 lines (223 loc) · 9.53 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

* Main.java

* Created on 1 òðàâíÿ 2007, 14:59

* To change this template, choose Tools | Template Manager

* and open the template in the editor.

package javaapplication8;

//import com.sun.org.apache.bcel.internal.classfile.JavaClass;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.lang.reflect.Constructor;

import java.lang.reflect.Method;

import java.net.URL;

import java.net.URLClassLoader;

import java.sql.*;

import java.util.Properties;

import java.util.jar.JarEntry;

import java.util.jar.JarInputStream;

/**

* @author Òåõíèê

class connect_to_firebird{

public static Class loadClass(String path_to_jar, String class_name){

Class return_value=null;

try{

URLClassLoader urlLoader = new URLClassLoader(new URL[]{new URL("file", null, path_to_jar)});

return_value=urlLoader.loadClass(class_name);

System.out.println("Loaded class:"+return_value.getName());

}catch(Throwable ex){

System.out.println(" error in load class"+ex.getMessage());

};

return return_value;

}

connect_to_firebird(){

java.sql.Driver driver=null;

java.sql.Connection connection=null;

java.sql.Statement statement=null;

java.sql.ResultSet rs=null;

java.sql.ResultSetMetaData rs_metadata=null;

String query;

//String databaseURL = "jdbc:firebirdsql:local:d:/work/sadik/sadik.gdb?sql_dialect=3";

String databaseURL = "jdbc:firebirdsql://localhost:3050/d:/work/sadik/sadik.gdb?sql_dialect=3";

String user = "SYSDBA";

String password = "masterkey";

String driver_name = "org.firebirdsql.jdbc.FBDriver";

try{

System.out.println("--- try to connect driver");

//System.loadLibrary("C:\\jaybird-full-2.1.1.jar");

// ïðîñòîå ïîäêëþ÷åíèå, êîòîðîå òðåáóåò â äèðåêòîðèè LIB æåñòêî ïðèâÿçàííîãî JAR

//Class.forName(class_name);

// Äèíàìè÷åñêîå ïîäêëþ÷åíèå:

// 1:

//driver=new org.firebirdsql.jdbc.FBDriver();

// 2:

Class current_class=loadClass("C:\\jaybird-full-2.1.1.jar","org.firebirdsql.jdbc.FBDriver");

System.out.println("--- Class:"+current_class.toString());

Constructor[] constr=current_class.getConstructors();

for(int counter=0;counter<constr.length;counter++){

System.out.println(counter+" : "+constr[counter].getName());

}

Object object=current_class.newInstance();

driver=(java.sql.Driver)current_class.newInstance();

System.out.println("--- Driver:"+driver.toString());

java.sql.DriverManager.registerDriver(driver);

// 3:

URL url=new URL("jar:file:C:/jaybird-full-2.1.1.jar!/");

URLClassLoader class_loader=new URLClassLoader(new URL[]{url});

System.out.println("URLClassLoader:"+class_loader);

Class.forName(class_name,true,class_loader);

System.out.println("loaded class");

// 4:

//URL url = new URL("jar:file:/c:/jaybird-full-2.1.1.jar!/");

URL url=new URL("file", null, "C:\\jaybird-full-2.1.1.jar");

URLClassLoader ucl = new URLClassLoader(new URL[]{url},null);

System.out.println("---URLClassLoader:"+ucl);

Class class_value=Class.forName(driver_name,true,ucl);

System.out.println("---classValue:"+class_value);

Object d_object=class_value.newInstance();

System.out.println("---object Driver:"+d_object);

driver = (Driver)class_value.newInstance();

System.out.println("---to Driver:"+driver);

DriverManager.registerDriver(driver);

System.out.println("---register Driver");

Properties properties=new Properties();

properties.put("user",user);

properties.put("password",password);

//org.firebirdsql.pool.FBWrappingDataSource dataSource=new org.firebirdsql.pool.FBWrappingDataSource();

//connection=java.sql.DriverManager.getConnection(databaseURL,user,password);

connection=driver.connect(databaseURL, properties);

System.out.println("firebird connected");

statement=connection.createStatement();

query="SELECT KOD_1NF FROM S_DDZ";

if(statement.execute(query)==true){

System.out.println("Query OK");

// âûâîä ðåçóëüòàòà

rs=statement.getResultSet();

// âûâîä çàãîëîâêîâ

rs_metadata=rs.getMetaData();

for(int i=0;i<rs_metadata.getColumnCount();i++){

System.out.print(" >"+rs_metadata.getColumnLabel(i+1)+"< ");

}

System.out.println("\n");

// âûâîä äàííûõ

while(rs.next()){

for(int i=0;i<rs_metadata.getColumnCount();i++){

System.out.print(" "+rs.getInt(i+1)+" ");

}

System.out.println("\n");

}

System.out.println("end of MySQL");

}

}catch(Exception e){

System.out.println(">>>Error "+e.getMessage());

}catch(Throwable ex){

System.out.println(">>>Throwable: "+ex.getMessage());

}

class connect_to_mysql{

String driver_name="org.gjt.mm.mysql.Driver";

java.sql.Connection connection=null;

java.sql.Driver driver=null;

java.sql.Statement statement=null;

java.sql.ResultSet rs=null;

java.sql.ResultSetMetaData rs_metadata=null;

String query;

//String driver="org.gjt.mm.mysql.Driver";

connect_to_mysql(){

try{

// ïîïûòêà ïîäêëþ÷åíèÿ ê áàçå äàííûõ

Class.forName(driver_name);

connection=java.sql.DriverManager.getConnection("jdbc:mysql://localhost:3306/db_temp","root","");

System.out.println("connected");

statement=connection.createStatement();

query="SELECT * FROM TABLE_1";

if(statement.execute(query)==true){

System.out.println("Query OK");

// âûâîä ðåçóëüòàòà

rs=statement.getResultSet();

// âûâîä çàãîëîâêîâ

rs_metadata=rs.getMetaData();

for(int i=0;i<rs_metadata.getColumnCount();i++){

System.out.print(" >"+rs_metadata.getColumnLabel(i+1)+"< ");

}

System.out.println("\n");

// âûâîä äàííûõ

while(rs.next()){

for(int i=0;i<rs_metadata.getColumnCount();i++){

System.out.print(" "+rs.getString(i+1)+" ");

}

System.out.println("\n");

}

System.out.println("end of MySQL");

}

else {

System.out.println("Error in query");

}

catch(Exception e){

System.out.println("Error in connect to MySQl \n"+e.getMessage());

}

public class Main {

/** Creates a new instance of Main */

public Main() {

}

/**

* @param args the command line arguments

public static void main(String[] args) {

// TODO code application logic here

try{

//new connect_to_mysql();

new connect_to_firebird();

}

catch(java.lang.NoClassDefFoundError e){

System.out.println(">>> Error in thread main:"+e.getMessage());

}

private static URLClassLoader getURLClassLoader(URL jarURL) {

return new URLClassLoader(new URL[]{jarURL});

}

public static void addJAR(String path_to_file,String class_name){

try{

URLClassLoader urlLoader = getURLClassLoader(new URL("file", null, path_to_file));

Class class_value=urlLoader.loadClass(class_name);

System.out.println("Loaded class:"+class_value.getName());

JarInputStream jis = new JarInputStream(new FileInputStream(path_to_file));

JarEntry entry = jis.getNextJarEntry();

int loadedCount = 0, totalCount = 0;

}catch(Throwable ex){

System.out.println(" error in load class"+ex.getMessage());

};

}

public static void addURL(URL u) throws IOException {

URLClassLoader sysLoader = (URLClassLoader) ClassLoader.getSystemClassLoader();

URL urls[] = sysLoader.getURLs();

for (int i = 0; i < urls.length; i++) {

if (urls[i].toString().equalsIgnoreCase(u.toString())) {

System.out.println("URL " + u + " is already in the CLASSPATH");

return;

}

/*Class sysclass = URLClassLoader.class;

try {

Method method = sysclass.getDeclaredMethod("addURL", parameters);

method.setAccessible(true);

method.invoke(sysLoader, new Object[]{u});

} catch (Throwable t) {

t.printStackTrace();

throw new IOException("Error, could not add URL to system classloader");

}*/

}

java-code-example/Dynamic_Load_Class/Main.java at master · cherkavi/java-code-example · GitHub

Expand file tree

Breadcrumbs

Main.java

Latest commit

History

Breadcrumbs

Main.java

File metadata and controls