package er.extensions.foundation;
import java.util.Enumeration;
import org.apache.log4j.Logger;
import com.webobjects.foundation.NSArray;
import com.webobjects.foundation.NSMutableDictionary;
/**
* Provides flexible and powerful assertion. Is modeled a bit like log4j in that you can have multiple asserters that can have
* different behavior. In particular, each can be disabled, set to logging mode or set to raise an exception. Also you can set
* your own failure handler.
*
* In WebObjects.properties, you can have:
*
* <blockquote><pre>
* ERXAssert.instances=RAISE
* ERXAssert.instances.com.somepackage=LOG
* ERXAssert.instances.com.somepackage.someclass=RAISE
* </pre></blockquote>
*
* In your code's static initialization, you can write:
*
* <blockquote><pre>
* private static ERXAssert Assert = ERXAssert.getAssert(Foo.class);
* private static ERXAssert Pre = ERXAssert.PRE;
* private static ERXAssert Post = ERXAssert.POST;
* </pre></blockquote>
*
* And finally, in your methods, you call it via:
*
* <blockquote><pre>
* Pre.notNull(someObject);
* Assert.notNull("someObject" ,someObject);
* Post.notNull(someObject);
* </pre></blockquote>
*
* or you can use the supplied assertors directly
*
* <blockquote><pre>
* ERXAssert.DURING.notNull("someObject", someObject);
* </pre></blockquote>
*
* Most of this code is derived from Jonathan "Wolf" Rentzsch's JAssert, which can be found here:
* <a href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/redshed/JAssert/">http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/redshed/JAssert/</a>.
**/
public class ERXAssert {
private static final NSMutableDictionary _instances = new NSMutableDictionary();
private static final NSMutableDictionary _handlersForKey = new NSMutableDictionary();
private static final Logger log = Logger.getLogger(ERXAssert.class);
public static final ERXAssert DURING;
public static final ERXAssert PRE;
public static final ERXAssert POST;
//-------------------------------------------
// Public assertion failure handler interface
public interface FailureHandler {
public void handleFailure(ERXAssert instance, String message);
}
protected static class EmptyHandler implements FailureHandler {
public void handleFailure(ERXAssert instance, String message) {
}
}
protected static class LoggingHandler implements FailureHandler {
public void handleFailure(ERXAssert instance, String message) {
String output = "Assertion failed (" + instance.name() + "): ";
if(message != null)
output += message;
log.error(output, new Throwable());
}
}
protected static class ThrowingHandler implements FailureHandler {
protected void raise(String message) {
throw new RuntimeException(message);
}
public void handleFailure(ERXAssert instance, String message) {
String output = "Assertion failed (" + instance.name() + "): ";
if(message != null)
output += message;
raise(output);
}
}
protected static class IllegalArgumentHandler extends ThrowingHandler {
@Override
protected void raise(String message) {
throw new IllegalArgumentException(message);
}
}
protected static class IllegalStateHandler extends ThrowingHandler {
@Override
protected void raise(String message) {
throw new IllegalStateException(message);
}
}
static {
_handlersForKey.setObjectForKey(new EmptyHandler(), "NONE");
_handlersForKey.setObjectForKey(new LoggingHandler(), "LOG");
_handlersForKey.setObjectForKey(new ThrowingHandler(), "RAISE");
PRE = getAssert("PRE");
POST = getAssert("POST");
DURING = getAssert("DURING");
PRE.setFailureHandler(new IllegalArgumentHandler());
POST.setFailureHandler(new IllegalStateHandler());
DURING.setFailureHandler(new IllegalStateHandler());
}
public static ERXAssert getAssert(String name) {
synchronized(_instances) {
ERXAssert value = (ERXAssert)_instances.objectForKey(name);
if(value == null) {
value = new ERXAssert(name);
_instances.setObjectForKey(value, name);
}
setLevel(value);
return value;
}
}
protected static String getLevel(ERXAssert value) {
NSArray arr = NSArray.componentsSeparatedByString(value.name(), ".");
String prefix = "ERXAssert.instances";
String level = System.getProperty(prefix);
if(level == null)
level = "LOG";
for(Enumeration e = arr.objectEnumerator(); e.hasMoreElements(); ) {
String s = (String)e.nextElement();
String possibleLevel = System.getProperty(prefix + "." + s);
if(possibleLevel != null) {
level = possibleLevel;
}
prefix = prefix + "." + s;
}
return level;
}
public static void setHandlerForLevel(FailureHandler object, String level) {
_handlersForKey.setObjectForKey(object, level);
}
protected static void setLevel(ERXAssert value) {
String level = getLevel(value);
FailureHandler handler = (FailureHandler)_handlersForKey.objectForKey(level);
if(handler == null) {
throw new IllegalStateException("Can't find handler for level \"" + level + "\" for assert: " + value.name());
}
value.setFailureHandler(handler);
}
public static ERXAssert getAssert(Class c) {
return getAssert(c.getName());
}
public static ERXAssert getAssert(String prefix, Class c) {
return getAssert(prefix + "." + c.getName());
}
protected String _name;
private ERXAssert(String value) {
_name = value;
}
//----------------------------------
// Public client assertion interface
public void isTrue(boolean value) {
if(value == false) fail("expected true");
}
public void isTrue(String message, boolean value) {
if(value == false) fail(message, "expected true");
}
public void isFalse(boolean value) {
if(value) fail("expected false");
}
public void isFalse(String message, boolean value) {
if(value) fail(message, "expected false");
}
public void isNull(Object value) {
if(value != null) fail("expected null object, got " + value);
}
public void isNull(String message, Object value) {
if(value != null) fail(message, "expected null, got " + value);
}
public void notNull(Object value) {
if(value == null) fail("expected non-null object");
}
public void notNull(String message, Object value) {
if(value == null) fail(message, "expected non-null object");
}
public void isEmpty(String value) {
if(value != null && !value.equals("")) fail("expected empty String, got " + value);
}
public void notEmpty(String value) {
if(value == null)
fail("expected non-empty String, got null");
else if(value.equals(""))
fail("expected non-empty String, got empty string");
}
public void isZero(int value) {
if(value != 0) fail("expected zero int, got " + value);
}
public void isZero(long value) {
if(value != 0L) fail("expected zero long, got " + value);
}
public void isZero(double value) {
if(value != 0.0) fail("expected zero double, got " + value);
}
public void notZero(int value) {
if(value == 0) fail("expected non-zero int, got " + value);
}
public void notZero(long value) {
if(value == 0L) fail("expected non-zero long, got " + value);
}
public void notZero(double value) {
if(value == 0.0) fail("expected non-zero double, got " + value);
}
public void isNegative(int value) {
if(value >= 0) fail("expected negative int, got " + value);
}
public void isNegative(long value) {
if(value >= 0L) fail("expected negative long, got " + value);
}
public void isNegative(double value) {
if(value >= 0.0) fail("expected negative double, got " + value);
}
public void notNegative(int value) {
if(value < 0) fail("expected non-negative int, got " + value);
}
public void notNegative(long value) {
if(value < 0L) fail("expected non-negative long, got " + value);
}
public void notNegative(double value) {
if(value < 0.0) fail("expected non-negative double, got " + value);
}
public void isPositive(int value) {
if(value < 0) fail("expected positive int, got " + value);
}
public void isPositive(long value) {
if(value < 0L) fail("expected positive long, got " + value);
}
public void isPositive(double value) {
if(value < 0.0) fail("expected positive double, got " + value);
}
public void notPositive(int value) {
if(value >= 0) fail("expected non-positive int, got " + value);
}
public void notPositive(long value) {
if(value >= 0L) fail("expected non-positive long, got " + value);
}
public void notPositive(double value) {
if(value >= 0.0) fail("expected non-positive double, got " + value);
}
public void isEqual(int value1, int value2) {
if(value1 != value2) fail("expected equal integers, got " + value1 + " & " + value2);
}
public void isEqual(String message, int value1, int value2) {
if(value1 != value2) fail(message, "expected equal integers, got " + value1 + " & " + value2);
}
public void isEqual(long value1, long value2) {
if(value1 != value2) fail("expected equal longs, got " + value1 + " & " + value2);
}
public void isEqual(double value1, double value2) {
if(value1 != value2) fail("expected equal doubles, got " + value1 + " & " + value2);
}
public void isEqual(Object value1, Object value2) {
if((value1 != null && !value1.equals(value2)) || value2 == null ) fail("expected equal objects, got " + value1 + " & " + value2);
}
public void isEqual(String message, Object value1, Object value2) {
if((value1 != null && !value1.equals(value2)) || value2 == null ) fail(message, "expected equal objects, got " + value1 + " & " + value2);
}
public void notEqual(int value1, int value2) {
if(value1 == value2) fail("expected unequal integers, got " + value1 + " & " + value2);
}
public void notEqual(long value1, long value2) {
if(value1 == value2) fail("expected unequal longs, got " + value1 + " & " + value2);
}
public void notEqual(double value1, double value2) {
if(value1 == value2) fail("expected unequal doubles, got " + value1 + " & " + value2);
}
public void notEqual(Object value1, Object value2) {
if((value1 != null && value1.equals(value2)) || value2 == null ) fail("expected unequal objects, got " + value1 + " & " + value2);
}
public void lessThan(int value1, int value2) {
if(value1 >= value2) fail("expected " + value1 + " to be less than " + value2);
}
public void lessThan(long value1, long value2) {
if(value1 >= value2) fail("expected " + value1 + " to be less than " + value2);
}
public void lessThan(double value1, double value2) {
if(value1 >= value2) fail("expected " + value1 + " to be less than " + value2);
}
public void lessThanOrEqual(int value1, int value2) {
if(value1 > value2) fail("expected " + value1 + " to be less than or equal to " + value2);
}
public void lessThanOrEqual(long value1, long value2) {
if(value1 > value2) fail("expected " + value1 + " to be less than or equal to " + value2);
}
public void lessThanOrEqual(double value1, double value2) {
if(value1 > value2) fail("expected " + value1 + " to be less than or equal to " + value2);
}
public void greaterThan(int value1, int value2) {
if(value1 <= value2) fail("expected " + value1 + " to be greater than " + value2);
}
public void greaterThan(long value1, long value2) {
if(value1 <= value2) fail("expected " + value1 + " to be greater than " + value2);
}
public void greaterThan(double value1, double value2) {
if(value1 <= value2) fail("expected " + value1 + " to be greater than " + value2);
}
public void greaterThanOrEqual(int value1, int value2) {
if(value1 < value2) fail("expected " + value1 + " to be greater than or equal to " + value2);
}
public void greaterThanOrEqual(long value1, long value2) {
if(value1 < value2) fail("expected " + value1 + " to be greater than or equal to " + value2);
}
public void greaterThanOrEqual(double value1, double value2) {
if(value1 < value2) fail("expected " + value1 + " to be greater than or equal to " + value2);
}
public void unknownSwitchCase(int value) {
fail("unknown switch case: " + value);
}
public String name() {
return _name;
}
public FailureHandler failureHandler() {
return _failureHandler;
}
public void setFailureHandler(FailureHandler handler) {
_failureHandler = handler;
}
protected FailureHandler _failureHandler;
public void fail(String message) {
_failureHandler.handleFailure(this, message);
}
public void fail(String message, String supplement) {
_failureHandler.handleFailure(this, message + ": " + supplement);
}
}