Package org.opennms.core.utils

Class StringUtils

java.lang.Object

org.opennms.core.utils.StringUtils

public abstract class StringUtils
extends java.lang.Object

Constructor Summary

Constructors

Constructor	Description
StringUtils()

Method Summary

Modifier and Type	Method	Description
static java.lang.String[]	createCommandArray(java.lang.String s)	Convenience method for creating arrays of strings suitable for use as command-line parameters when executing an external process.
static java.lang.String[]	createCommandArray(java.lang.String s, char delim)	Deprecated. Use createCommandArray(String s) instead.
static boolean	equalsTrimmed(java.lang.String a, java.lang.String b)	This is an optimized version of: return a != null && a.trim().equals(b) that avoids creating a trimmed substring of A before comparison.
static java.lang.String	getHumanReadableByteCount(long bytes, boolean si)	Copied from https://programming.guide/java/formatting-byte-size-to-human-readable-format.html
static boolean	hasText(java.lang.String text)
static boolean	isEmpty(java.lang.String text)
static boolean	isLocalWindowsPath(java.lang.String path)
static java.lang.String	iso8601LocalOffsetString(java.util.Date d)
static java.lang.String	iso8601OffsetString(java.util.Date d, java.time.ZoneId zone, java.time.temporal.ChronoUnit truncateTo)
static java.lang.Integer	parseDecimalInt(java.lang.String value)
static java.lang.Integer	parseDecimalInt(java.lang.String value, boolean throwExceptions)	This is a quick and dirty parser for String representations of decimal integers.
static java.lang.Double	parseDouble(java.lang.String value, java.lang.Double defaultValue)
static java.lang.Integer	parseInt(java.lang.String value, java.lang.Integer defaultValue)
static java.lang.Long	parseLong(java.lang.String value, java.lang.Long defaultValue)
static java.lang.String	prettyXml(java.lang.String xml)	Uses the Xalan javax.transform classes to indent an XML string properly so that it is easier to read.
static java.lang.String	stripExtraQuotes(java.lang.String string)
static java.lang.String	toStringEfficiently(java.util.Date date)	NMS-9091: This method calls Date.toString() but then calls Date.setTime(long) so that internally, the Date.cdate field is deallocated.
static java.lang.String	truncate(java.lang.String name, int length)	truncate
static java.util.Optional<java.lang.String>	truncatePrefix(java.lang.String input, java.lang.String prefix)	Removes a prefix from the input but returns the input only if the prefix was present.

Methods inherited from class java.lang.Object

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

Constructor Detail

StringUtils

public StringUtils()

Method Detail

createCommandArray

public static java.lang.String[] createCommandArray(java.lang.String s,
                                                    char delim)

Deprecated.

Use createCommandArray(String s) instead.

Convenience method for creating arrays of strings suitable for use as command-line parameters when executing an external process.

The default Runtime.execmethod will split a single string based on spaces, but it does not respect spaces within quotation marks, and it will leave the quotation marks in the resulting substrings. This method solves those problems by replacing all in-quote spaces with the given delimiter, removes the quotes, and then splits the resulting string by the remaining out-of-quote spaces. It then goes through each substring and replaces the delimiters with spaces.

Caveat: This method does not respect escaped quotes! It will simply remove them and leave the stray escape characters.

Parameters:

s - the string to split

delim - a char that does not already exist in s

Returns:

An array of strings split by spaces outside of quotes.

Throws:

java.lang.IllegalArgumentException - If s is null or if delim already exists in s.

createCommandArray

public static java.lang.String[] createCommandArray(java.lang.String s)

Convenience method for creating arrays of strings suitable for use as command-line parameters when executing an external process.

The default Runtime.exec method will split a single string based on spaces, but it does not respect spaces within quotation marks, and it will leave the quotation marks in the resulting substrings. This method solves those problems by preserving all in-quote spaces.

Caveat: This method does not respect escaped quotes! It will simply remove them and leave the stray escape characters.

Parameters:

s - the string to split

Returns:

An array of strings split by spaces outside of quotes.

Throws:

java.lang.IllegalArgumentException - If s is null.

truncate

public static java.lang.String truncate(java.lang.String name,
                                        int length)

truncate

Parameters:

name - a String object.

length - a int.

Returns:

a String object.

isLocalWindowsPath

public static boolean isLocalWindowsPath(java.lang.String path)

prettyXml

public static java.lang.String prettyXml(java.lang.String xml)
                                  throws javax.xml.transform.TransformerException

Uses the Xalan javax.transform classes to indent an XML string properly so that it is easier to read.

Throws:

javax.xml.transform.TransformerException

iso8601LocalOffsetString

public static java.lang.String iso8601LocalOffsetString(java.util.Date d)

iso8601OffsetString

public static java.lang.String iso8601OffsetString(java.util.Date d,
                                                   java.time.ZoneId zone,
                                                   java.time.temporal.ChronoUnit truncateTo)

stripExtraQuotes

public static java.lang.String stripExtraQuotes(java.lang.String string)

equalsTrimmed

public static boolean equalsTrimmed(java.lang.String a,
                                    java.lang.String b)

This is an optimized version of: return a != null && a.trim().equals(b) that avoids creating a trimmed substring of A before comparison. Instead A and B are compared in place.

Parameters:

a - string to trim before comparing

b - string to compare

Returns:

true if A equals B, after A is trimmed

isEmpty

public static boolean isEmpty(java.lang.String text)

hasText

public static boolean hasText(java.lang.String text)

toStringEfficiently

public static java.lang.String toStringEfficiently(java.util.Date date)

NMS-9091: This method calls Date.toString() but then calls Date.setTime(long) so that internally, the Date.cdate field is deallocated. This saves significant heap space for Date instances that are stored in long-lived collections.

• java.util.Date with only fastTime: 24 bytes
• java.util.Date with fastTime and cdate: 120 bytes

Parameters:

date -

Returns:

Value of date.toString()

parseDecimalInt

public static java.lang.Integer parseDecimalInt(java.lang.String value)

parseDecimalInt

public static java.lang.Integer parseDecimalInt(java.lang.String value,
                                                boolean throwExceptions)

This is a quick and dirty parser for String representations of decimal integers. It should be up to 2X faster than Integer.parseInt(String).

Parameters:

value - Positive or negative decimal string value

Returns:

Integer representing the string value

getHumanReadableByteCount

public static java.lang.String getHumanReadableByteCount(long bytes,
                                                         boolean si)

Copied from https://programming.guide/java/formatting-byte-size-to-human-readable-format.html

truncatePrefix

public static java.util.Optional<java.lang.String> truncatePrefix(java.lang.String input,
                                                                  java.lang.String prefix)

Removes a prefix from the input but returns the input only if the prefix was present.

Parameters:

input - the to remove the prefix from

prefix - the prefix to remove

Returns:

an present Optional containing the string without the prefix iff the string was prefixed, Optional.empty() otherwise.

parseInt

public static java.lang.Integer parseInt(java.lang.String value,
                                         java.lang.Integer defaultValue)

parseLong

public static java.lang.Long parseLong(java.lang.String value,
                                       java.lang.Long defaultValue)

parseDouble

public static java.lang.Double parseDouble(java.lang.String value,
                                           java.lang.Double defaultValue)