OnJava8-Examples/validating/GuavaAssertions.java
Bruce Eckel edd99881d7 Narrowed listing widths, fixed output
Also removed Preferences appendix
2017-05-10 11:45:39 -06:00

50 lines
1.2 KiB
Java

// validating/GuavaAssertions.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// Assertions that are always enabled.
import com.google.common.base.*;
import static com.google.common.base.Verify.*;
public class GuavaAssertions {
public static void main(String[] args) {
verify(2 + 2 == 4);
try {
verify(1 + 2 == 4);
} catch(VerifyException e) {
System.out.println(e);
}
try {
verify(1 + 2 == 4, "Bad math");
} catch(VerifyException e) {
System.out.println(e.getMessage());
}
try {
verify(1 + 2 == 4, "Bad math: %s", "not 4");
} catch(VerifyException e) {
System.out.println(e.getMessage());
}
String s = "";
s = verifyNotNull(s);
s = null;
try {
verifyNotNull(s);
} catch(VerifyException e) {
System.out.println(e.getMessage());
}
try {
verifyNotNull(
s, "Shouldn't be null: %s", "arg s");
} catch(VerifyException e) {
System.out.println(e.getMessage());
}
}
}
/* Output:
com.google.common.base.VerifyException
Bad math
Bad math: not 4
expected a non-null reference
Shouldn't be null: arg s
*/