Package com.reallifedeveloper.tools.test

Class TestUtil

java.lang.Object

com.reallifedeveloper.tools.test.TestUtil

public final class TestUtil
extends Object

Miscellaneous utility methods that are useful when testing.

Author:

RealLifeDeveloper

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DATE_FORMAT	The date format used by parseDate(String) ("yyyy-MM-dd").
static final String	DATE_TIME_FORMAT	The date+time format used by parseDateTime(String) ("yyyy-MM-dd HH:mm:ss").

Method Summary

Modifier and Type	Method	Description
static int	findFreePort()	Gives a port number on the local machine that no server process is listening to.
static @Nullable Object	getFieldValue(Object obj, String fieldName)	Gives the value of an object's field, which may be private.
static void	injectField(Object obj, String fieldName, @Nullable Object value)	Injects a value into an object's field, which may be private.
static Date	parseDate(String date)	Parses a date string on the form "yyyy-MM-dd" and returns the corresponding java.util.Date object.
static Date	parseDateTime(String dateTime)	Parses a date and time string on the form "yyyy-MM-dd HH:mm:ss" and returns the corresonding java.util.Date object.
static String	readResource(String resourceName)	Reads a string from a classpath resource, which is assumed to be UTF-8 encoded text.
static ZonedDateTime	utcNow()	Gives the current date and time in the UTC time zone.
static void	writeToFile(String s, String filename, Charset charset)	Writes a string to a file using the given character encoding.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DATE_FORMAT

public static final String DATE_FORMAT

The date format used by parseDate(String) ("yyyy-MM-dd").

See Also:

• Constant Field Values

DATE_TIME_FORMAT

public static final String DATE_TIME_FORMAT

The date+time format used by parseDateTime(String) ("yyyy-MM-dd HH:mm:ss").

See Also:

• Constant Field Values

Method Details

findFreePort

public static int findFreePort()
                        throws IOException

Gives a port number on the local machine that no server process is listening to.

Returns:

a free port number

Throws:

IOException - if an I/O error occurs when trying to open a socket

parseDate

public static Date parseDate(String date)

Parses a date string on the form "yyyy-MM-dd" and returns the corresponding java.util.Date object.

Parameters:

date - the date string to parse, should be on the form "yyyy-MM-dd"

Returns:

the java.util.Date corresponding to date

Throws:

IllegalArgumentException - if date cannot be parsed

parseDateTime

public static Date parseDateTime(String dateTime)

Parses a date and time string on the form "yyyy-MM-dd HH:mm:ss" and returns the corresonding java.util.Date object.

Parameters:

dateTime - the date+time string to parse, should be on the form "yyyy-MM-dd HH:mm:ss"

Returns:

the java.util.Date corresponding to dateTime

Throws:

IllegalArgumentException - if dateTime cannot be parsed

utcNow

public static ZonedDateTime utcNow()

Gives the current date and time in the UTC time zone.

Returns:

the current UTC date and time

writeToFile

public static void writeToFile(String s,
 String filename,
 Charset charset)
                        throws IOException

Writes a string to a file using the given character encoding.

Parameters:

s - the string to write

filename - the name of the file to write to

charset - the character set to use, e.g., java.nio.charset.StandardCharsets.UTF_8

Throws:

IOException - if writing to the file failed

readResource

public static String readResource(String resourceName)
                           throws IOException

Reads a string from a classpath resource, which is assumed to be UTF-8 encoded text.

Parameters:

resourceName - the name of the classpath resource to read

Returns:

a string representation of the classpath resource resourceName

Throws:

IOException - if reading the resource failed

injectField

public static void injectField(Object obj,
 String fieldName,
 @Nullable Object value)

Injects a value into an object's field, which may be private.

Parameters:

obj - the object in which to inject the value

fieldName - the name of the field

value - the value to inject, may be null

Throws:

IllegalArgumentException - if obj or fieldName is null

IllegalStateException - if reflecction failure

getFieldValue

public static @Nullable Object getFieldValue(Object obj,
 String fieldName)

Gives the value of an object's field, which may be private.

Parameters:

obj - the object containing the field

fieldName - the name of the field

Returns:

the value of the field fieldName in the object obj

Throws:

IllegalArgumentException - if obj or fieldName is null

IllegalStateException - if reflection failure