ej.sni

Class SNI

java.lang.Object

ej.sni.SNI

public class SNI
extends Object

This utility class provides methods to convert between Java & C strings.

Note: the platform default encoding is used. For converting using a different encoding, see String(byte[], String) & String.getBytes(String).

Example:

 package example;

 public class Foo {

        private static final int MAX_STRING_SIZE = 42; // including the '\0' character

        public void pushString(String str) {
                pushString(SNI.toCString(str));
        }

        public String pullString() {
                byte[] buffer = new byte[MAX_STRING_SIZE];
                pullString(buffer);
                return SNI.toJavaString(buffer);
        }

        private static native void pushString(byte[] str);

        private static native void pullString(byte[] buffer);

 }
 

 #include <sni.h>
 #include <string.h>

 #define MAX_STRING_SIZE 42

 static char gStr[MAX_STRING_SIZE];

 void Java_example_Foo_pushString(jbyte *str) {
     strncpy(gStr, (char*) str, MAX_STRING_SIZE);
 }

 void Java_example_Foo_pullString(jbyte *buffer) {
     strncpy((char*) buffer, gStr, MAX_STRING_SIZE);
 }
 

Method Summary

Modifier and Type	Method and Description
static byte[]	toCString(String javaString) Transforms a Java String into a C String. The platform default encoding is used to transform Java characters into C characters. The returned C String is a NULL terminated String (ends with '\0').
static void	toCString(String javaString, byte[] cString) Transforms a Java String into a C String. The platform default encoding is used to transform Java characters into C characters. The created C String is a NULL terminated String (ends with '\0').
static String	toJavaString(byte[] cString) Transforms a C String into a Java String, using platform default encoding.

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

toCString

public static byte[] toCString(String javaString)

Transforms a Java String into a C String.
The platform default encoding is used to transform Java characters into C characters.
The returned C String is a NULL terminated String (ends with '\0').

Parameters:

javaString - the Java String to convert.

Returns:

a new array that contains the C String representation of the given Java String.

Throws:

IllegalArgumentException - if javaString is null.

toCString

public static void toCString(String javaString,
                             byte[] cString)

Transforms a Java String into a C String.
The platform default encoding is used to transform Java characters into C characters.
The created C String is a NULL terminated String (ends with '\0'). The cString array length must be at least javaString.length()+1.

Parameters:

javaString - the Java String to convert.

cString - byte array which contains the C String.

Throws:

IllegalArgumentException - if javaString or cString is null.

ArrayIndexOutOfBoundsException - if cString is too small to contain the string.

toJavaString

public static String toJavaString(byte[] cString)

Transforms a C String into a Java String, using platform default encoding. The C String must be NULL terminated.

Parameters:

cString - byte array which contains the C String.

Returns:

a new Java String.

Throws:

IllegalArgumentException - if cString is null or its length is < 1.

IllegalArgumentException - if cString is not NULL terminated.