diff java/jdc/examples/UnixLibCExample.java @ 22:4ee8d6aa7721

- java binding cleanup, exposed free functions (not very oo, this entire binding) - java binding examples
author cslag
date Sat, 09 Apr 2016 18:18:34 -0500
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/java/jdc/examples/UnixLibCExample.java	Sat Apr 09 18:18:34 2016 -0500
@@ -0,0 +1,66 @@
+import org.dyncall.DC;
+
+// This example tries to make use of each call in the binding.
+class UnixLibCExample
+{
+   	public static void main(String args[])
+   	{
+		long lib = DC.loadLibrary("/usr/lib/libc.so");
+   		System.out.format("libc.so handle: %x\n", lib);
+
+		long f0 = DC.find(lib, "strlen");
+   		System.out.format("found strlen at: %x\n", f0);
+
+		long f1 = DC.find(lib, "strstr");
+   		System.out.format("found strstr at: %x\n", f1);
+
+		long f2 = DC.find(lib, "strncmp");
+   		System.out.format("found strncmp at: %x\n", f2);
+
+		long vm = DC.newCallVM(4096);
+		DC.reset(vm);
+   		System.out.format("dcGetError() = %d\n", DC.getError(vm));
+		DC.mode(vm, 1234567); // bogus mode, should set error
+   		System.out.format("dcGetError() = %d (after trying to set bogus mode)\n", DC.getError(vm));
+		DC.mode(vm, DC.C_DEFAULT); // good mode, should clear error
+   		System.out.format("dcGetError() = %d (after setting valid mode)\n", DC.getError(vm));
+
+		// String param.
+		DC.argString(vm, "This is a Java string of 33 chars");
+		int r0 = DC.callInt(vm, f0);
+   		System.out.format("strlen(\"This is a Java string of 33 chars\") = %d\n", r0);
+
+		// String param and string/pointer return.
+		DC.reset(vm);
+		DC.argString(vm, "This is a Java string");
+		DC.argString(vm, "Java");
+		String r1 = DC.callString(vm, f1); // will return a copy of the output string, not like a pointer in C
+   		System.out.format("strlen(\"This is a Java string\", \"Java\") = %s\n", r1);
+		long r1l = DC.callPointer(vm, f1); // test returning the pointer as long
+   		System.out.format("strlen(\"This is a Java string\", \"Java\") = 0x%x (returned pointer, pointless here, but serves as example)\n", r1l);
+
+		DC.reset(vm);
+		DC.argString(vm, "This is a Java string");
+		DC.argString(vm, "This is");
+		DC.argInt(vm, 6);
+		int r2 = DC.callInt(vm, f2);
+   		System.out.format("strlen(\"This is a Java string\", \"This is\", 6) = %d\n", r2);
+		DC.reset(vm);
+		DC.argString(vm, "This is a Java string");
+		DC.argString(vm, "This is");
+		DC.argInt(vm, 8);
+		r2 = DC.callInt(vm, f2);
+   		System.out.format("strlen(\"This is a Java string\", \"This is\", 8) = %d\n", r2);
+
+		//DC.reset(vm);
+		//DC.argDouble(vm,  2.);
+		//DC.argDouble(vm, 10.);
+		//double r1 = DC.callDouble(vm, f1);
+   		//System.out.format("pow(2., 10.) = %f\n", r1);
+
+		// Done, cleanup.
+		DC.freeCallVM(vm);
+		DC.freeLibrary(lib);
+	}
+}
+