kamailio/modules/app_java

app_java Module

Konstantin Mosesov

Edited by

Konstantin Mosesov

Copyright © 2013 Konstantin Mosesov
__________________________________________________________________

Table of Contents

1. Admin Guide

1. Overview
2. Dependencies

2.1. Kamailio Modules
2.2. External Libraries or Applications

3. Java runtime

3.1.

4. Parameters

4.1. class_name (string)
4.2. child_init_method (string)
4.3. java_options (string)
4.4. force_cmd_exec (int)

5. Functions

5.1. Common requirements
5.2. java_method_exec(method, method_signature, [param1[,
param2[, ...]]])

5.3. java_staticmethod_exec(method, method_signature,
[param1[, param2[, ...]]])

5.4. java_s_method_exec(method, method_signature, [param1[,
param2[, ...]]])

5.5. java_s_staticmethod_exec(method, method_signature,
[param1[, param2[, ...]]])

6. Java Module API

6.1. Minimal program skeleton

List of Examples

1.1. Set class_name parameter
1.2. Set child_init_method parameter
1.3. Set java_options parameter
1.4. Set java_options parameter (live configuration)
1.5. Set java_options parameter (verbose configuration)
1.6. Set java_options parameter (debug configuration)
1.7. Set force_cmd_exec parameter
1.8. Signature: "V"
1.9. Signature: "Ljava/lang/String;I"
1.10. Signature: "ZB"
1.11. Signature: "V"
1.12. Signature: "Ljava/lang/String;I"
1.13. Signature: "ZB"
1.14. Signature: "V"
1.15. Signature: "Ljava/lang/String;I"
1.16. Signature: "ZB"
1.17. Signature: "V"
1.18. Signature: "Ljava/lang/String;I"
1.19. Signature: "ZB"
1.20. Minimal program skeleton

Chapter 1. Admin Guide

Table of Contents

1. Overview
2. Dependencies

2.1. Kamailio Modules
2.2. External Libraries or Applications

3. Java runtime

3.1.

4. Parameters

4.1. class_name (string)
4.2. child_init_method (string)
4.3. java_options (string)
4.4. force_cmd_exec (int)

5. Functions

5.1. Common requirements
5.2. java_method_exec(method, method_signature, [param1[, param2[,
...]]])

5.3. java_staticmethod_exec(method, method_signature, [param1[,
param2[, ...]]])

5.4. java_s_method_exec(method, method_signature, [param1[,
param2[, ...]]])

5.5. java_s_staticmethod_exec(method, method_signature, [param1[,
param2[, ...]]])

6. Java Module API

6.1. Minimal program skeleton

1. Overview

This module allows executing Java compiled classes from config file,
exporting functions to access the SIP message from Java using Java
Native Interface (JNI).

2. Dependencies

2.1. Kamailio Modules
2.2. External Libraries or Applications

2.1. Kamailio Modules

The following modules must be loaded before this module:
* none.

2.2. External Libraries or Applications

The following packages are runtime libraries, required to launch
* java-common Base of all Java packages.
* default-jre Standard Java or Java compatible Runtime.
* gcj-jre Java runtime environment using GIJ/classpath.
* libgcj12 (>=12) Java runtime library for use with gcj.

The following packages are optional, required for development
* ant Java based build tool like make.
* ant-contrib Collection of tasks, types and other tools for Apache
Ant.
* ant-gcj Java based build tool like make (GCJ).
* default-jdk Standard Java or Java compatible Development Kit
* gcj-jdk gcj and classpath development tools for Java(TM)
* libgcj13-dev (>=12) Java development headers for use with gcj
* jdk JDK Development Kit (either oracle jdk or openjdk)

The following libraries or applications must be compiled before running
Kamailio with this module loaded:

The following packages are runtime libraries, required to launch
* .class
* kamailio.jar

3. Java runtime

3.1.

3.1.

Java runtime library (JRE or JDK) is required to use this module.

4. Parameters

4.1. class_name (string)
4.2. child_init_method (string)
4.3. java_options (string)
4.4. force_cmd_exec (int)

4.1. class_name (string)

The class name should have the same compiled file name. If the value is
"Kamailio", then the compiled file should be named as "Kamailio.class".

Default value is “Kamailio”.

Example 1.1. Set class_name parameter
...
modparam("app_java", "class_name", "Kamailio")
...

4.2. child_init_method (string)

TBD.

Default value is “child_init”.

Example 1.2. Set child_init_method parameter
...
modparam("app_java", "child_init_method", "my_mod_init")
...

4.3. java_options (string)

Java options for Java Virtual Machine. For more info read java docs

Default value is “-Djava.compiler=NONE”.

Example 1.3. Set java_options parameter
...
modparam("app_java", "java_options", "-Djava.compiler=NONE")
...

Example 1.4. Set java_options parameter (live configuration)
...
# Assumes "application java folder" is located at /opt/kamailio/java
modparam("app_java", "java_options", "-Djava.compiler=NONE -Djava.class.path=/pa
th/to/kamailio/modules:/opt/kamailio/java:/opt/kamailio/java/kamailio.jar")
...

Example 1.5. Set java_options parameter (verbose configuration)
...
# Assumes "application java folder" is located at /opt/kamailio/java
modparam("app_java", "java_options", "-verbose:gc,class,jni -Djava.compiler=NONE
-Djava.class.path=/path/to/kamailio/modules:/opt/kamailio/java:/opt/kamailio/ja
va/kamailio.jar")
...

Example 1.6. Set java_options parameter (debug configuration)
...
# Assumes "application java folder" is located at /opt/kamailio/java
modparam("app_java", "java_options", "-Xdebug -verbose:gc,class,jni -Djava.compi
ler=NONE -Djava.class.path=/path/to/kamailio/modules:/opt/kamailio/java:/opt/kam
ailio/java/kamailio.jar")
...

4.4. force_cmd_exec (int)

This parameter forces execution a kamailio comnmand with java native
method “KamExec”. # Note: this is an untested yet feature, may cause
(but may not) a memory leaks if used from embedded languages.

Default value is “0 (off)”.

Example 1.7. Set force_cmd_exec parameter
...
modparam("app_java", "force_cmd_exec", 1)
...

5. Functions

5.1. Common requirements
5.2. java_method_exec(method, method_signature, [param1[, param2[,
...]]])

5.3. java_staticmethod_exec(method, method_signature, [param1[,
param2[, ...]]])

5.4. java_s_method_exec(method, method_signature, [param1[, param2[,
...]]])

5.5. java_s_staticmethod_exec(method, method_signature, [param1[,
param2[, ...]]])

5.1. Common requirements

Each function has a required parameter “method_signature”. For more
info see Determine the signature of a method. Signature represents the
variable type. The mapping between the Java type and C type is
Type Chararacter
boolean Z
byte B
char C
double D
float F
int I
long J
object L
short S
void V
Note that to specify an object, the "L" is followed by the objec
t's class name and ends with a semi-colon, ';' .

app_java supports the following signatures:
Primitives: Z,B,C,D,F,I,J,L,S,V
Objects:
Ljava/lang/Boolean;
Ljava/lang/Byte;
Ljava/lang/Character;
Ljava/lang/Double;
Ljava/lang/Float;
Ljava/lang/Integer;
Ljava/lang/Long;
Ljava/lang/Short;
Ljava/lang/String;
NULL parameter: V

Each parameter passed to function will be cast according to given signat
ure.

Parameters are optional, ommitting a parameter meant the passed value is
NULL.
Parameters count should be exactly the same as signature count.
Note 1: Arrays representation (symbol '[') is not supported yet.
Note 2: You shall use a correct signature, e.g. the following examples o
f combinations are invalid:
java_method_exec("ExampleMethod", "ZI", "False");
java_method_exec("ExampleMethod", "LI", "something", "5");

5.2. java_method_exec(method, method_signature, [param1[, param2[, ...]]])

Executes a java class method method. Parameter method_signature is
required.
* Example 1.8. Signature: "V"
Kamailio prototype
java_method_exec("ExampleMethod", "V");
Java prototype
public int ExampleMethod();
Example of usage:
# Kamailio
java_method_exec("ExampleMethod", "V");

# Java
public int ExampleMethod()
{
... do something;
return 1;
}
* Example 1.9. Signature: "Ljava/lang/String;I"
Kamailio prototype
java_method_exec("ExampleMethod", "Ljava/lang/String;I", "Hello world", "5");
Java prototype
public int ExampleMethod(String param1, int param2);
In the above scenario parameter 2 ("5") will be cast to integer
representation.
Example of usage:
# Kamailio
java_method_exec("ExampleMethod", "Ljava/lang/String;I", "$mb", "$ml");

# Java
public int ExampleMethod(String SipMessageBuffer, int SipMessageLenght)
{
... do something with buffer;
return 1;
}
* Example 1.10. Signature: "ZB"
Kamailio prototype
java_method_exec("ExampleMethod", "ZB", "true", "0x05");
Java prototype
public int ExampleMethod(boolean param1, byte param2);
In the above scenario parameter 1 ("true") will be cast to boolean
representation.
Example of usage:
# Kamailio
java_method_exec("ExampleMethod", "ZB", "true", "0x05");

# Java
public int ExampleMethod(boolean flagSet, byte bFlag);
{
if (flagSet)
{
... do something with flags;
}
return 1;
}

5.3. java_staticmethod_exec(method, method_signature, [param1[, param2[,
...]]])

Executes a java static method method. Parameter method_signature is
required.
* Example 1.11. Signature: "V"
Kamailio prototype
java_staticmethod_exec("ExampleMethod", "V");
Java prototype
public static int ExampleMethod();
Example of usage:
# Kamailio
java_staticmethod_exec("ExampleMethod", "V");

# Java
public static int ExampleMethod()
{
... do something;
return 1;
}
* Example 1.12. Signature: "Ljava/lang/String;I"
Kamailio prototype
java_staticmethod_exec("ExampleMethod", "Ljava/lang/String;I", "Hello world", "5
");
Java prototype
public static int ExampleMethod(String param1, int param2);
In the above scenario parameter 2 ("5") will be cast to integer
representation.
Example of usage:
# Kamailio
java_staticmethod_exec("ExampleMethod", "Ljava/lang/String;I", "$mb", "$ml");

# Java
public static int ExampleMethod(String SipMessageBuffer, int SipMessageLenght)
{
... do something with buffer;
return 1;
}
* Example 1.13. Signature: "ZB"
Kamailio prototype
java_staticmethod_exec("ExampleMethod", "ZB", "true", "0x05");
Java prototype
public static int ExampleMethod(boolean param1, byte param2);
In the above scenario parameter 1 ("true") will be cast to boolean
representation.
Example of usage:
# Kamailio
java_staticmethod_exec("ExampleMethod", "ZB", "true", "0x05");

# Java
public static int ExampleMethod(boolean flagSet, byte bFlag);
{
if (flagSet)
{
... do something with flags;
}
return 1;
}

5.4. java_s_method_exec(method, method_signature, [param1[, param2[, ...]]])

Executes a java class synchronized method method. Parameter
method_signature is required.

For more info see Synchronized Methods
* Example 1.14. Signature: "V"
Kamailio prototype
java_s_method_exec("ExampleMethod", "V");
Java prototype
public synchronized int ExampleMethod();
Example of usage:
# Kamailio
java_s_method_exec("ExampleMethod", "V");

# Java
public synchronized int ExampleMethod()
{
... do something;
return 1;
}
* Example 1.15. Signature: "Ljava/lang/String;I"
Kamailio prototype
java_s_method_exec("ExampleMethod", "Ljava/lang/String;I", "Hello world", "5");
Java prototype
public synchronized int ExampleMethod(String param1, int param2);
In the above scenario parameter 2 ("5") will be cast to integer
representation.
Example of usage:
# Kamailio
java_s_method_exec("ExampleMethod", "Ljava/lang/String;I", "$mb", "$ml");

# Java
public synchronized int ExampleMethod(String SipMessageBuffer, int SipMessageLen
ght)
{
... do something with buffer;
return 1;
}
* Example 1.16. Signature: "ZB"
Kamailio prototype
java_s_method_exec("ExampleMethod", "ZB", "true", "0x05");
Java prototype
public synchronized int ExampleMethod(boolean param1, byte param2);
In the above scenario parameter 1 ("true") will be cast to boolean
representation.
Example of usage:
# Kamailio
java_s_method_exec("ExampleMethod", "ZB", "true", "0x05");

# Java
public synchronized int ExampleMethod(boolean flagSet, byte bFlag);
{
if (flagSet)
{
... do something with flags;
}
return 1;
}

5.5. java_s_staticmethod_exec(method, method_signature, [param1[, param2[,
...]]])

Executes a java synchronized static method method. Parameter
method_signature is required.

For more info see Synchronized Methods
* Example 1.17. Signature: "V"
Kamailio prototype
java_s_staticmethod_exec("ExampleMethod", "V");
Java prototype
public static synchronized int ExampleMethod();
Example of usage:
# Kamailio
java_s_staticmethod_exec("ExampleMethod", "V");

# Java
public static synchronized int ExampleMethod()
{
... do something;
return 1;
}
* Example 1.18. Signature: "Ljava/lang/String;I"
Kamailio prototype
java_s_staticmethod_exec("ExampleMethod", "Ljava/lang/String;I", "Hello world",
"5");
Java prototype
public static synchronized int ExampleMethod(String param1, int param2);
In the above scenario parameter 2 ("5") will be cast to integer
representation.
Example of usage:
# Kamailio
java_s_staticmethod_exec("ExampleMethod", "Ljava/lang/String;I", "$mb", "$ml");

# Java
public static synchronized int ExampleMethod(String SipMessageBuffer, int SipMes
sageLenght)
{
... do something with buffer;
return 1;
}
* Example 1.19. Signature: "ZB"
Kamailio prototype
java_s_staticmethod_exec("ExampleMethod", "ZB", "true", "0x05");
Java prototype
public static synchronized int ExampleMethod(boolean param1, byte param2);
In the above scenario parameter 1 ("true") will be cast to boolean
representation.
Example of usage:
# Kamailio
java_s_staticmethod_exec("ExampleMethod", "ZB", "true", "0x05");

# Java
public static synchronized int ExampleMethod(boolean flagSet, byte bFlag);
{
if (flagSet)
{
... do something with flags;
}
return 1;
}

6. Java Module API

6.1. Minimal program skeleton

6.1. Minimal program skeleton

Example 1.20. Minimal program skeleton

import org.siprouter.*;
import org.siprouter.NativeInterface.*;

public class Kamailio extends NativeMethods
{
/* Here you should specify a full path to app_java.so */
static
{
System.load("/opt/kamailio/lib/kamailio/modules/
app_java.so");
}

/* Constructor. Do not remove !!! */
public Kamailio()
{
}

/*
This method should be executed for each children process, immedi
ately after forking.
Required. Do not remove !!!
*/
public int child_init(int rank)
{
return 1;
}
}