cn.t.util.common.Assert Maven / Gradle / Ivy
package cn.t.util.common;
import java.util.Collection;
import java.util.Map;
/**
*
*/
public class Assert {
/**
* Assert a boolean expression, throwing an {@code IllegalStateException}
* if the expression evaluates to {@code false}.
* Call {@link #isTrue} if you wish to throw an {@code IllegalArgumentException}
* on an assertion failure.
*
Assert.state(id == null, "The id property must not already be initialized");
*
* @param expression a boolean expression
* @param message the exception message to use if the assertion fails
* @throws IllegalStateException if {@code expression} is {@code false}
*/
public static void state(boolean expression, String message) {
if (!expression) {
throw new IllegalStateException(message);
}
}
/**
* @param expression xxx
* @deprecated as of 4.3.7, in favor of {@link #state(boolean, String)}
*/
@Deprecated
public static void state(boolean expression) {
state(expression, "[Assertion failed] - this state invariant must be true");
}
/**
* Assert a boolean expression, throwing an {@code IllegalArgumentException}
* if the expression evaluates to {@code false}.
* Assert.isTrue(i > 0, "The value must be greater than zero");
*
* @param expression a boolean expression
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if {@code expression} is {@code false}
*/
public static void isTrue(boolean expression, String message) {
if (!expression) {
throw new IllegalArgumentException(message);
}
}
/**
* @param expression xxx
* @deprecated as of 4.3.7, in favor of {@link #isTrue(boolean, String)}
*/
@Deprecated
public static void isTrue(boolean expression) {
isTrue(expression, "[Assertion failed] - this expression must be true");
}
/**
* Assert that an object is {@code null}.
* Assert.isNull(value, "The value must be null");
*
* @param object the object to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the object is not {@code null}
*/
public static void isNull(Object object, String message) {
if (object != null) {
throw new IllegalArgumentException(message);
}
}
/**
* @param object xxx
* @deprecated as of 4.3.7, in favor of {@link #isNull(Object, String)}
*/
@Deprecated
public static void isNull(Object object) {
isNull(object, "[Assertion failed] - the object argument must be null");
}
/**
* Assert that an object is not {@code null}.
* Assert.notNull(clazz, "The class must not be null");
*
* @param object the object to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the object is {@code null}
*/
public static void notNull(Object object, String message) {
if (object == null) {
throw new IllegalArgumentException(message);
}
}
/**
* @param object xxx
* @deprecated as of 4.3.7, in favor of {@link #notNull(Object, String)}
*/
@Deprecated
public static void notNull(Object object) {
notNull(object, "[Assertion failed] - this argument is required; it must not be null");
}
/**
* Assert that the given String is not empty; that is,
* it must not be {@code null} and not the empty String.
* Assert.hasLength(name, "Name must not be empty");
*
* @param text the String to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the text is empty
*/
public static void hasLength(String text, String message) {
if (!StringUtil.hasLength(text)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param text xxx
* @deprecated as of 4.3.7, in favor of {@link #hasLength(String, String)}
*/
@Deprecated
public static void hasLength(String text) {
hasLength(text,
"[Assertion failed] - this String argument must have length; it must not be null or empty");
}
/**
* Assert that the given String contains valid text content; that is, it must not
* be {@code null} and must contain at least one non-whitespace character.
* Assert.hasText(name, "'name' must not be empty");
*
* @param text the String to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the text does not contain valid text content
*/
public static void hasText(String text, String message) {
if (!StringUtil.hasText(text)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param text xxx
* @deprecated as of 4.3.7, in favor of {@link #hasText(String, String)}
*/
@Deprecated
public static void hasText(String text) {
hasText(text,
"[Assertion failed] - this String argument must have text; it must not be null, empty, or blank");
}
/**
* Assert that the given text does not contain the given substring.
* Assert.doesNotContain(name, "rod", "Name must not contain 'rod'");
*
* @param textToSearch the text to search
* @param substring the substring to find within the text
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the text contains the substring
*/
public static void doesNotContain(String textToSearch, String substring, String message) {
if (StringUtil.hasLength(textToSearch) && StringUtil.hasLength(substring) &&
textToSearch.contains(substring)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param textToSearch xxx
* @param substring xxx
* @deprecated as of 4.3.7, in favor of {@link #doesNotContain(String, String, String)}
*/
@Deprecated
public static void doesNotContain(String textToSearch, String substring) {
doesNotContain(textToSearch, substring,
"[Assertion failed] - this String argument must not contain the substring [" + substring + "]");
}
/**
* Assert that an array contains elements; that is, it must not be
* {@code null} and must contain at least one element.
* Assert.notEmpty(array, "The array must contain elements");
*
* @param array the array to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the object array is {@code null} or contains no elements
*/
public static void notEmpty(Object[] array, String message) {
if (ObjectUtil.isEmpty(array)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param array xxx
* @deprecated as of 4.3.7, in favor of {@link #notEmpty(Object[], String)}
*/
@Deprecated
public static void notEmpty(Object[] array) {
notEmpty(array, "[Assertion failed] - this array must not be empty: it must contain at least 1 element");
}
/**
* Assert that an array contains no {@code null} elements.
* Note: Does not complain if the array is empty!
*
Assert.noNullElements(array, "The array must contain non-null elements");
*
* @param array the array to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the object array contains a {@code null} element
*/
public static void noNullElements(Object[] array, String message) {
if (array != null) {
for (Object element : array) {
if (element == null) {
throw new IllegalArgumentException(message);
}
}
}
}
/**
* @param array xxx
* @deprecated as of 4.3.7, in favor of {@link #noNullElements(Object[], String)}
*/
@Deprecated
public static void noNullElements(Object[] array) {
noNullElements(array, "[Assertion failed] - this array must not contain any null elements");
}
/**
* Assert that a collection contains elements; that is, it must not be
* {@code null} and must contain at least one element.
* Assert.notEmpty(collection, "Collection must contain elements");
*
* @param collection the collection to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the collection is {@code null} or
* contains no elements
*/
public static void notEmpty(Collection collection, String message) {
if (CollectionUtil.isEmpty(collection)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param collection xxx
* @deprecated as of 4.3.7, in favor of {@link #notEmpty(Collection, String)}
*/
@Deprecated
public static void notEmpty(Collection collection) {
notEmpty(collection,
"[Assertion failed] - this collection must not be empty: it must contain at least 1 element");
}
/**
* Assert that a Map contains entries; that is, it must not be {@code null}
* and must contain at least one entry.
* Assert.notEmpty(map, "Map must contain entries");
*
* @param map the map to check
* @param message the exception message to use if the assertion fails
* @throws IllegalArgumentException if the map is {@code null} or contains no entries
*/
public static void notEmpty(Map map, String message) {
if (CollectionUtil.isEmpty(map)) {
throw new IllegalArgumentException(message);
}
}
/**
* @param map xxx
* @deprecated as of 4.3.7, in favor of {@link #notEmpty(Map, String)}
*/
@Deprecated
public static void notEmpty(Map map) {
notEmpty(map, "[Assertion failed] - this map must not be empty; it must contain at least one entry");
}
/**
* Assert that the provided object is an instance of the provided class.
* Assert.instanceOf(Foo.class, foo, "Foo expected");
*
* @param type the type to check against
* @param obj the object to check
* @param message a message which will be prepended to provide further context.
* If it is empty or ends in ":" or ";" or "," or ".", a full exception message
* will be appended. If it ends in a space, the name of the offending object's
* type will be appended. In any other case, a ":" with a space and the name
* of the offending object's type will be appended.
* @throws IllegalArgumentException if the object is not an instance of type
*/
public static void isInstanceOf(Class type, Object obj, String message) {
notNull(type, "Type to check against must not be null");
if (!type.isInstance(obj)) {
instanceCheckFailed(type, obj, message);
}
}
/**
* Assert that the provided object is an instance of the provided class.
* Assert.instanceOf(Foo.class, foo);
*
* @param type the type to check against
* @param obj the object to check
* @throws IllegalArgumentException if the object is not an instance of type
*/
public static void isInstanceOf(Class type, Object obj) {
isInstanceOf(type, obj, "");
}
/**
* Assert that {@code superType.isAssignableFrom(subType)} is {@code true}.
* Assert.isAssignable(Number.class, myClass, "Number expected");
*
* @param superType the super type to check against
* @param subType the sub type to check
* @param message a message which will be prepended to provide further context.
* If it is empty or ends in ":" or ";" or "," or ".", a full exception message
* will be appended. If it ends in a space, the name of the offending sub type
* will be appended. In any other case, a ":" with a space and the name of the
* offending sub type will be appended.
* @throws IllegalArgumentException if the classes are not assignable
*/
public static void isAssignable(Class superType, Class subType, String message) {
notNull(superType, "Super type to check against must not be null");
if (subType == null || !superType.isAssignableFrom(subType)) {
assignableCheckFailed(superType, subType, message);
}
}
/**
* Assert that {@code superType.isAssignableFrom(subType)} is {@code true}.
* Assert.isAssignable(Number.class, myClass);
*
* @param superType the super type to check
* @param subType the sub type to check
* @throws IllegalArgumentException if the classes are not assignable
*/
public static void isAssignable(Class superType, Class subType) {
isAssignable(superType, subType, "");
}
private static void instanceCheckFailed(Class type, Object obj, String msg) {
String className = (obj != null ? obj.getClass().getName() : "null");
String result = "";
boolean defaultMessage = true;
if (StringUtil.hasLength(msg)) {
if (endsWithSeparator(msg)) {
result = msg + " ";
} else {
result = messageWithTypeName(msg, className);
defaultMessage = false;
}
}
if (defaultMessage) {
result = result + ("Object of class [" + className + "] must be an instance of " + type);
}
throw new IllegalArgumentException(result);
}
private static void assignableCheckFailed(Class superType, Class subType, String msg) {
String result = "";
boolean defaultMessage = true;
if (StringUtil.hasLength(msg)) {
if (endsWithSeparator(msg)) {
result = msg + " ";
} else {
result = messageWithTypeName(msg, subType);
defaultMessage = false;
}
}
if (defaultMessage) {
result = result + (subType + " is not assignable to " + superType);
}
throw new IllegalArgumentException(result);
}
private static boolean endsWithSeparator(String msg) {
return (msg.endsWith(":") || msg.endsWith(";") || msg.endsWith(",") || msg.endsWith("."));
}
private static String messageWithTypeName(String msg, Object typeName) {
return msg + (msg.endsWith(" ") ? "" : ": ") + typeName;
}
}