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-rw-r--r--Examples/java/variables/Makefile18
-rw-r--r--Examples/java/variables/example.c91
-rw-r--r--Examples/java/variables/example.h6
-rw-r--r--Examples/java/variables/example.i49
-rw-r--r--Examples/java/variables/index.html85
-rw-r--r--Examples/java/variables/runme.java97
6 files changed, 346 insertions, 0 deletions
diff --git a/Examples/java/variables/Makefile b/Examples/java/variables/Makefile
new file mode 100644
index 0000000..968c92c
--- /dev/null
+++ b/Examples/java/variables/Makefile
@@ -0,0 +1,18 @@
+TOP = ../..
+SWIG = $(TOP)/../preinst-swig
+SRCS = example.c
+TARGET = example
+INTERFACE = example.i
+SWIGOPT =
+
+all:: java
+
+java::
+ $(MAKE) -f $(TOP)/Makefile SRCS='$(SRCS)' SWIG='$(SWIG)' \
+ SWIGOPT='$(SWIGOPT)' TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' java
+ javac *.java
+
+clean::
+ $(MAKE) -f $(TOP)/Makefile java_clean
+
+check: all
diff --git a/Examples/java/variables/example.c b/Examples/java/variables/example.c
new file mode 100644
index 0000000..aa4ffe9
--- /dev/null
+++ b/Examples/java/variables/example.c
@@ -0,0 +1,91 @@
+/* File : example.c */
+
+/* I'm a file containing some C global variables */
+
+/* Deal with Microsoft's attempt at deprecating C standard runtime functions */
+#if !defined(SWIG_NO_CRT_SECURE_NO_DEPRECATE) && defined(_MSC_VER)
+# define _CRT_SECURE_NO_DEPRECATE
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "example.h"
+
+int ivar = 0;
+short svar = 0;
+long lvar = 0;
+unsigned int uivar = 0;
+unsigned short usvar = 0;
+unsigned long ulvar = 0;
+signed char scvar = 0;
+unsigned char ucvar = 0;
+char cvar = 0;
+float fvar = 0;
+double dvar = 0;
+char *strvar = 0;
+const char cstrvar[] = "Goodbye";
+int *iptrvar = 0;
+char name[256] = "Dave";
+char path[256] = "/home/beazley";
+
+
+/* Global variables involving a structure */
+Point *ptptr = 0;
+Point pt = { 10, 20 };
+
+/* A variable that we will make read-only in the interface */
+int status = 1;
+
+/* A debugging function to print out their values */
+
+void print_vars() {
+ printf("ivar = %d\n", ivar);
+ printf("svar = %d\n", svar);
+ printf("lvar = %ld\n", lvar);
+ printf("uivar = %u\n", uivar);
+ printf("usvar = %u\n", usvar);
+ printf("ulvar = %lu\n", ulvar);
+ printf("scvar = %d\n", scvar);
+ printf("ucvar = %u\n", ucvar);
+ printf("fvar = %g\n", fvar);
+ printf("dvar = %g\n", dvar);
+ printf("cvar = %c\n", cvar);
+ printf("strvar = %s\n", strvar ? strvar : "(null)");
+ printf("cstrvar = %s\n", cstrvar ? cstrvar : "(null)");
+ printf("iptrvar = %p\n", iptrvar);
+ printf("name = %s\n", name);
+ printf("ptptr = %p (%d, %d)\n", ptptr, ptptr ? ptptr->x : 0, ptptr ? ptptr->y : 0);
+ printf("pt = (%d, %d)\n", pt.x, pt.y);
+ printf("status = %d\n", status);
+}
+
+/* A function to create an integer (to test iptrvar) */
+
+int *new_int(int value) {
+ int *ip = (int *) malloc(sizeof(int));
+ *ip = value;
+ return ip;
+}
+
+/* A function to create a point */
+
+Point *new_Point(int x, int y) {
+ Point *p = (Point *) malloc(sizeof(Point));
+ p->x = x;
+ p->y = y;
+ return p;
+}
+
+char * Point_print(Point *p) {
+ static char buffer[256];
+ if (p) {
+ sprintf(buffer,"(%d,%d)", p->x,p->y);
+ } else {
+ sprintf(buffer,"null");
+ }
+ return buffer;
+}
+
+void pt_print() {
+ printf("(%d, %d)\n", pt.x, pt.y);
+}
diff --git a/Examples/java/variables/example.h b/Examples/java/variables/example.h
new file mode 100644
index 0000000..0f7e895
--- /dev/null
+++ b/Examples/java/variables/example.h
@@ -0,0 +1,6 @@
+/* File: example.h */
+
+typedef struct {
+ int x,y;
+} Point;
+
diff --git a/Examples/java/variables/example.i b/Examples/java/variables/example.i
new file mode 100644
index 0000000..591b871
--- /dev/null
+++ b/Examples/java/variables/example.i
@@ -0,0 +1,49 @@
+/* File : example.i */
+%module example
+%{
+#include "example.h"
+%}
+
+/* Some global variable declarations */
+%inline %{
+extern int ivar;
+extern short svar;
+extern long lvar;
+extern unsigned int uivar;
+extern unsigned short usvar;
+extern unsigned long ulvar;
+extern signed char scvar;
+extern unsigned char ucvar;
+extern char cvar;
+extern float fvar;
+extern double dvar;
+extern char *strvar;
+extern const char cstrvar[];
+extern int *iptrvar;
+extern char name[256];
+
+extern Point *ptptr;
+extern Point pt;
+%}
+
+
+/* Some read-only variables */
+
+%immutable;
+
+%inline %{
+extern int status;
+extern char path[256];
+%}
+
+%mutable;
+
+/* Some helper functions to make it easier to test */
+%inline %{
+extern void print_vars();
+extern int *new_int(int value);
+extern Point *new_Point(int x, int y);
+extern char *Point_print(Point *p);
+extern void pt_print();
+%}
+
diff --git a/Examples/java/variables/index.html b/Examples/java/variables/index.html
new file mode 100644
index 0000000..07b19d4
--- /dev/null
+++ b/Examples/java/variables/index.html
@@ -0,0 +1,85 @@
+<html>
+<head>
+<title>SWIG:Examples:java:variables</title>
+</head>
+
+<body bgcolor="#ffffff">
+
+<tt>SWIG/Examples/java/variables/</tt>
+<hr>
+
+<H2>Wrapping C Global Variables</H2>
+
+<p>
+When a C global variable appears in an interface file, SWIG tries to
+wrap it using a technique known as "variable linking." The idea is
+pretty simple---we try to create a Java variable that magically
+retrieves or updates the value of the underlying C variable when it is
+accessed. Click <a href="example.i">here</a> to see a SWIG interface with some variable
+declarations in it.
+
+
+<p>Click <a href="../../../Doc/Manual/Java.html#global_variables">here</a> for the section on global variables in the SWIG and Java documentation.</p>
+<h2>Manipulating Variables from Java</h2>
+
+C variables are accessed through getters and setters from Java. Unfortunately this is the only way to get current values from variables because it is not possible to overload the dot operator in Java. All global variables are accessible from the module class. For example if the module class is called 'example', the global variable
+
+<blockquote>
+<pre>
+double foo;
+</pre>
+</blockquote>
+
+will be accessed in the Java module as
+<blockquote>
+<pre>
+example.get_foo();
+example.set_foo(12.3);
+</pre>
+</blockquote>
+
+Click <a href="runme.java">here</a> to see the example program that updates and prints
+out the values of the variables using this technique.
+
+<h2>Key points</h2>
+
+<ul>
+<li>When a global variable has the type "<tt>char *</tt>", SWIG manages it as a character
+string. However, whenever the value of such a variable is set from Java, the old
+value is destroyed using <tt>free()</tt> or <tt>delete</tt> (the choice of which depends
+on whether or not SWIG was run with the -c++ option).
+<li><tt>signed char</tt> and <tt>unsigned char</tt> are handled as small 8-bit integers.
+<li>String array variables such as '<tt>char name[256]</tt>' are managed as Java strings, but
+when setting the value, the result is truncated to the maximum length of the array. Furthermore, the string is assumed to be null-terminated.
+<li>When structures and classes are used as global variables, they are mapped into pointers.
+Getting the "value" returns a pointer to the global variable. Setting the value of a structure results in a memory copy from a pointer to the global.
+</ul>
+
+<h2>Creating read-only variables</h2>
+
+The <tt>%immutable</tt> and <tt>%mutable</tt> directives can be used to
+specify a collection of read-only variables. For example:
+
+<blockquote>
+<pre>
+%immutable;
+int status;
+double blah;
+...
+%mutable;
+</pre>
+</blockquote>
+
+The <tt>%immutable</tt> directive remains in effect until it is explicitly disabled
+using the <tt>%mutable</tt> directive.
+
+<h2>Comments</h2>
+<ul>
+<li>Management of global variables is one of the most problematic aspects
+of C/C++ wrapping because the Java interface and resulting memory management
+is much trickier than simply creating a wrapper function.
+</ul>
+
+</body>
+</html>
+<hr>
diff --git a/Examples/java/variables/runme.java b/Examples/java/variables/runme.java
new file mode 100644
index 0000000..361a30f
--- /dev/null
+++ b/Examples/java/variables/runme.java
@@ -0,0 +1,97 @@
+// This example illustrates global variable access from Java.
+
+import java.lang.reflect.*;
+
+public class runme {
+ static {
+ try {
+ System.loadLibrary("example");
+ } catch (UnsatisfiedLinkError e) {
+ System.err.println("Native code library failed to load. See the chapter on Dynamic Linking Problems in the SWIG Java documentation for help.\n" + e);
+ System.exit(1);
+ }
+ }
+
+ public static void main(String argv[]) {
+
+// Try to set the values of some global variables
+
+ example.setIvar(42);
+ example.setSvar((short)-31000);
+ example.setLvar(65537);
+ example.setUivar(123456);
+ example.setUsvar(61000);
+ example.setUlvar(654321);
+ example.setScvar((byte)-13);
+ example.setUcvar((short)251);
+ example.setCvar('S');
+ example.setFvar((float)3.14159);
+ example.setDvar(2.1828);
+ example.setStrvar("Hello World");
+ example.setIptrvar(example.new_int(37));
+ example.setPtptr(example.new_Point(37,42));
+ example.setName("Bill");
+
+ // Now print out the values of the variables
+
+ System.out.println( "Variables (values printed from Java)" );
+
+ System.out.println( "ivar =" + example.getIvar() );
+ System.out.println( "svar =" + example.getSvar() );
+ System.out.println( "lvar =" + example.getLvar() );
+ System.out.println( "uivar =" + example.getUivar() );
+ System.out.println( "usvar =" + example.getUsvar() );
+ System.out.println( "ulvar =" + example.getUlvar() );
+ System.out.println( "scvar =" + example.getScvar() );
+ System.out.println( "ucvar =" + example.getUcvar() );
+ System.out.println( "fvar =" + example.getFvar() );
+ System.out.println( "dvar =" + example.getDvar() );
+ System.out.println( "cvar =" + (char)example.getCvar() );
+ System.out.println( "strvar =" + example.getStrvar() );
+ System.out.println( "cstrvar =" + example.getCstrvar() );
+ System.out.println( "iptrvar =" + Long.toHexString(SWIGTYPE_p_int.getCPtr(example.getIptrvar())) );
+ System.out.println( "name =" + example.getName() );
+ System.out.println( "ptptr =" + Long.toHexString(SWIGTYPE_p_Point.getCPtr(example.getPtptr())) + example.Point_print(example.getPtptr()) );
+ System.out.println( "pt =" + Long.toHexString(SWIGTYPE_p_Point.getCPtr(example.getPt())) + example.Point_print(example.getPt()) );
+
+ System.out.println( "\nVariables (values printed from C)" );
+
+ example.print_vars();
+
+ System.out.println( "\nNow I'm going to try and modify some read only variables" );
+
+ System.out.println( " Trying to set 'path'" );
+ try {
+ Method m = example.class.getDeclaredMethod("setPath", new Class[] {String.class});
+ m.invoke(example.class, new Object[] {"Whoa!"} );
+ System.out.println( "Hey, what's going on?!?! This shouldn't work" );
+ }
+ catch (NoSuchMethodException e) {
+ System.out.println( "Good." );
+ }
+ catch (Throwable t) {
+ System.out.println( "You shouldn't see this!" );
+ }
+
+ System.out.println( " Trying to set 'status'" );
+ try {
+ Method m = example.class.getDeclaredMethod("setStatus", new Class[] {Integer.class});
+ m.invoke(example.class, new Object[] {new Integer(0)} );
+ System.out.println( "Hey, what's going on?!?! This shouldn't work" );
+ }
+ catch (NoSuchMethodException e) {
+ System.out.println( "Good." );
+ }
+ catch (Throwable t) {
+ System.out.println( "You shouldn't see this!" );
+ }
+
+ System.out.println( "\nI'm going to try and update a structure variable.\n" );
+
+ example.setPt(example.getPtptr());
+
+ System.out.println( "The new value is" );
+ example.pt_print();
+ System.out.println( "You should see the value" + example.Point_print(example.getPtptr()) );
+ }
+}
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