Test for a host being reachable using ICMP "ping" packets & echo operations. Ping packets are very reliable for assessing reachability in a LAN or WAN, but they do not get through any well-configured firewall. Echo (port 7) may.
This condition turns unknown host exceptions into false conditions. This is because on a laptop, DNS is one of the first services lost when the network goes; you are implicitly offline.
If a URL is supplied instead of a host, the hostname is extracted and used in the test--all other parts of the URL are discarded.
The test may not work through firewalls; that is, something may be reachable using a protocol such as HTTP, while the lower level ICMP packets get dropped on the floor. Similarly, a host may be detected as reachable with ICMP, but not reachable on other ports (i.e. port 80), because of firewalls.
| Modifier and Type | Field and Description |
|---|---|
| public static final int | DEFAULT_TIMEOUT
The default timeout. |
| public static final String | ERROR_BAD_TIMEOUT
Error when invalid timeout value is defined |
| public static final String | ERROR_BAD_URL
Error message when an invalid url is used. |
| public static final String | ERROR_BOTH_TARGETS
Error message when url and host are specified. |
| public static final String | ERROR_NO_HOST_IN_URL
Error message when no hostname in url. |
| public static final String | ERROR_NO_HOSTNAME
Error when no hostname is defined |
| public static final String | ERROR_ON_NETWORK
Network error message is seen. |
| private String | |
| public static final String | METHOD_NAME
The method name to look for in InetAddress |
| public static final String | MSG_NO_REACHABLE_TEST
Error message when no reachably test avail. |
| private static final int | |
| private int | |
| private String | |
| private static final String | WARN_UNKNOWN_HOST
Unknown host message is seen. |
| Access | Constructor and Description |
|---|---|
| public |
| Modifier and Type | Method and Description |
|---|---|
| public boolean | Returns: true if the condition is true.Implements org. |
| private boolean | |
| public void | |
| public void | setTimeout(final int
the timeout in seconds. timeout)Set the timeout for the reachability test in seconds. |
| public void |
| DEFAULT_TIMEOUT | back to summary |
|---|---|
| public static final int DEFAULT_TIMEOUT The default timeout. | |
| ERROR_BAD_TIMEOUT | back to summary |
|---|---|
| public static final String ERROR_BAD_TIMEOUT Error when invalid timeout value is defined | |
| ERROR_BAD_URL | back to summary |
|---|---|
| public static final String ERROR_BAD_URL Error message when an invalid url is used. | |
| ERROR_BOTH_TARGETS | back to summary |
|---|---|
| public static final String ERROR_BOTH_TARGETS Error message when url and host are specified. | |
| ERROR_NO_HOST_IN_URL | back to summary |
|---|---|
| public static final String ERROR_NO_HOST_IN_URL Error message when no hostname in url. | |
| ERROR_NO_HOSTNAME | back to summary |
|---|---|
| public static final String ERROR_NO_HOSTNAME Error when no hostname is defined | |
| ERROR_ON_NETWORK | back to summary |
|---|---|
| public static final String ERROR_ON_NETWORK Network error message is seen. | |
| host | back to summary |
|---|---|
| private String host | |
| METHOD_NAME | back to summary |
|---|---|
| public static final String METHOD_NAME
Deprecated Since 1.10.6 The method name to look for in InetAddress | |
| MSG_NO_REACHABLE_TEST | back to summary |
|---|---|
| public static final String MSG_NO_REACHABLE_TEST Error message when no reachably test avail. | |
| SECOND | back to summary |
|---|---|
| private static final int SECOND | |
| timeout | back to summary |
|---|---|
| private int timeout | |
| url | back to summary |
|---|---|
| private String url | |
| WARN_UNKNOWN_HOST | back to summary |
|---|---|
| private static final String WARN_UNKNOWN_HOST Unknown host message is seen. | |
| IsReachable | back to summary |
|---|---|
| public IsReachable() | |
| eval | back to summary |
|---|---|
| public boolean eval() throws BuildException Implements org. Evaluate the condition.
| |
| isNullOrEmpty | back to summary |
|---|---|
| private boolean isNullOrEmpty(final String string) emptyness test
| |
| setHost | back to summary |
|---|---|
| public void setHost(final String host) Set the host to ping.
| |
| setTimeout | back to summary |
|---|---|
| public void setTimeout(final int timeout) Set the timeout for the reachability test in seconds.
| |
| setUrl | back to summary |
|---|---|
| public void setUrl(final String url) Set the URL from which to extract the hostname.
| |