本文实例为大家分享了Java常用工具类 的具体代码，供大家参考，具体内容如下
UUID工具类
package com.jarvis.base.util; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; /** * A class that represents an immutable universally unique identifier (UUID). * A UUID represents a 128-bit value. * *There exist different variants of these global identifiers. The methods * of this class are for manipulating the Leach-Salz variant, although the * constructors allow the creation of any variant of UUID (described below). *
*The layout of a variant 2 (Leach-Salz) UUID is as follows: *
* The most significant long consists of the following unsigned fields: ** 0xFFFFFFFF00000000 time_low * 0x00000000FFFF0000 time_mid * 0x000000000000F000 version * 0x0000000000000FFF time_hi ** The least significant long consists of the following unsigned fields: ** 0xC000000000000000 variant * 0x3FFF000000000000 clock_seq * 0x0000FFFFFFFFFFFF node ** *The variant field contains a value which identifies the layout of * the UUID. The bit layout described above is valid only for * a UUID with a variant value of 2, which indicates the * Leach-Salz variant. *
*The version field holds a value that describes the type of this * UUID. There are four different basic types of UUIDs: time-based, * DCE security, name-based, and randomly generated UUIDs. These types * have a version value of 1, 2, 3 and 4, respectively. *
*For more information including algorithms used to create UUIDs, * see the Internet-Draft UUIDs and GUIDs * or the standards body definition at * ISO/IEC 11578:1996. * * @version 1.14, 07/12/04 * @since 1.5 */ @Deprecated public final class UUID implements java.io.Serializable { /** * Explicit serialVersionUID for interoperability. */ private static final long serialVersionUID = -4856846361193249489L; /* * The most significant 64 bits of this UUID. * * @serial */ private final long mostSigBits; /** * The least significant 64 bits of this UUID. * * @serial */ private final long leastSigBits; /* * The version number associated with this UUID. Computed on demand. */ private transient int version = -1; /* * The variant number associated with this UUID. Computed on demand. */ private transient int variant = -1; /* * The timestamp associated with this UUID. Computed on demand. */ private transient volatile long timestamp = -1; /* * The clock sequence associated with this UUID. Computed on demand. */ private transient int sequence = -1; /* * The node number associated with this UUID. Computed on demand. */ private transient long node = -1; /* * The hashcode of this UUID. Computed on demand. */ private transient int hashCode = -1; /* * The random number generator used by this class to create random * based UUIDs. */ private static volatile SecureRandom numberGenerator = null; // Constructors and Factories /* * Private constructor which uses a byte array to construct the new UUID. */ private UUID(byte[] data) { long msb = 0; long lsb = 0; for (int i = 0; i < 8; i++) msb = (msb << 8) | (data[i] & 0xff); for (int i = 8; i < 16; i++) lsb = (lsb << 8) | (data[i] & 0xff); this.mostSigBits = msb; this.leastSigBits = lsb; } /** * Constructs a new UUID using the specified data. * mostSigBits is used for the most significant 64 bits * of the UUID and leastSigBits becomes the * least significant 64 bits of the UUID. * * @param mostSigBits * @param leastSigBits */ public UUID(long mostSigBits, long leastSigBits) { this.mostSigBits = mostSigBits; this.leastSigBits = leastSigBits; } /** * Static factory to retrieve a type 4 (pseudo randomly generated) UUID. *
* TheUUIDis generated using a cryptographically strong * pseudo random number generator. * * @return a randomly generated UUID. */ @SuppressWarnings("unused") public static UUID randomUUID() { SecureRandom ng = numberGenerator; if (ng == null) { numberGenerator = ng = new SecureRandom(); } byte[] randomBytes = new byte[16]; ng.nextBytes(randomBytes); randomBytes[6] &= 0x0f; /* clear version */ randomBytes[6] |= 0x40; /* set to version 4 */ randomBytes[8] &= 0x3f; /* clear variant */ randomBytes[8] |= 0x80; /* set to IETF variant */ UUID result = new UUID(randomBytes); return new UUID(randomBytes); } /** * Static factory to retrieve a type 3 (name based) UUID based on * the specified byte array. * * @param name a byte array to be used to construct a UUID. * @return a UUID generated from the specified array. */ public static UUID nameUUIDFromBytes(byte[] name) { MessageDigest md; try { md = MessageDigest.getInstance("MD5"); } catch (NoSuchAlgorithmException nsae) { throw new InternalError("MD5 not supported"); } byte[] md5Bytes = md.digest(name); md5Bytes[6] &= 0x0f; /* clear version */ md5Bytes[6] |= 0x30; /* set to version 3 */ md5Bytes[8] &= 0x3f; /* clear variant */ md5Bytes[8] |= 0x80; /* set to IETF variant */ return new UUID(md5Bytes); } /** * Creates a UUID from the string standard representation as * described in the {@link #toString} method. * * @param name a string that specifies a UUID. * @return a UUID with the specified value. * @throws IllegalArgumentException if name does not conform to the * string representation as described in {@link #toString}. */ public static UUID fromString(String name) { String[] components = name.split("-"); if (components.length != 5) throw new IllegalArgumentException("Invalid UUID string: " + name); for (int i = 0; i < 5; i++) components[i] = "0x" + components[i]; long mostSigBits = Long.decode(components[0]).longValue(); mostSigBits <<= 16; mostSigBits |= Long.decode(components[1]).longValue(); mostSigBits <<= 16; mostSigBits |= Long.decode(components[2]).longValue(); long leastSigBits = Long.decode(components[3]).longValue(); leastSigBits <<= 48; leastSigBits |= Long.decode(components[4]).longValue(); return new UUID(mostSigBits, leastSigBits); } // Field Accessor Methods /** * Returns the least significant 64 bits of this UUID's 128 bit value. * * @return the least significant 64 bits of this UUID's 128 bit value. */ public long getLeastSignificantBits() { return leastSigBits; } /** * Returns the most significant 64 bits of this UUID's 128 bit value. * * @return the most significant 64 bits of this UUID's 128 bit value. */ public long getMostSignificantBits() { return mostSigBits; } /** * The version number associated with this UUID. The version * number describes how this UUID was generated. * * The version number has the following meaning:*
-
*
- 1 Time-based UUID *
- 2 DCE security UUID *
- 3 Name-based UUID *
- 4 Randomly generated UUID *
*
-
*
- 0 Reserved for NCS backward compatibility *
- 2 The Leach-Salz variant (used by this class) *
- 6 Reserved, Microsoft Corporation backward compatibility *
- 7 Reserved for future definition *
The 60 bit timestamp value is constructed from the time_low, * time_mid, and time_hi fields of this UUID. The resulting * timestamp is measured in 100-nanosecond units since midnight, * October 15, 1582 UTC.
*
* The timestamp value is only meaningful in a time-based UUID, which * has version type 1. If this UUID is not a time-based UUID then * this method throws UnsupportedOperationException. * * @throws UnsupportedOperationException if this UUID is not a * version 1 UUID. */ public long timestamp() { if (version() != 1) { throw new UnsupportedOperationException("Not a time-based UUID"); } long result = timestamp; if (result < 0) { result = (mostSigBits & 0x0000000000000FFFL) << 48; result |= ((mostSigBits >> 16) & 0xFFFFL) << 32; result |= mostSigBits >>> 32; timestamp = result; } return result; } /** * The clock sequence value associated with this UUID. * *The 14 bit clock sequence value is constructed from the clock * sequence field of this UUID. The clock sequence field is used to * guarantee temporal uniqueness in a time-based UUID.
*
* The clockSequence value is only meaningful in a time-based UUID, which * has version type 1. If this UUID is not a time-based UUID then * this method throws UnsupportedOperationException. * * @return the clock sequence of this UUID. * @throws UnsupportedOperationException if this UUID is not a * version 1 UUID. */ public int clockSequence() { if (version() != 1) { throw new UnsupportedOperationException("Not a time-based UUID"); } if (sequence < 0) { sequence = (int) ((leastSigBits & 0x3FFF000000000000L) >>> 48); } return sequence; } /** * The node value associated with this UUID. * *The 48 bit node value is constructed from the node field of * this UUID. This field is intended to hold the IEEE 802 address * of the machine that generated this UUID to guarantee spatial * uniqueness.
*
* The node value is only meaningful in a time-based UUID, which * has version type 1. If this UUID is not a time-based UUID then * this method throws UnsupportedOperationException. * * @return the node value of this UUID. * @throws UnsupportedOperationException if this UUID is not a * version 1 UUID. */ public long node() { if (version() != 1) { throw new UnsupportedOperationException("Not a time-based UUID"); } if (node < 0) { node = leastSigBits & 0x0000FFFFFFFFFFFFL; } return node; } // Object Inherited Methods /** * Returns aString object representing this
* UUID.
*
* The UUID string representation is as described by this BNF : *
* UUID =* * @return a string representation of this UUID. */ public String toString() { return (digits(mostSigBits >> 32, 8) + "-" + digits(mostSigBits >> 16, 4) + "-" + digits(mostSigBits, 4) + "-" + digits(leastSigBits >> 48, 4) + "-" + digits(leastSigBits, 12)); } /** * Returns val represented by the specified number of hex digits. */ private static String digits(long val, int digits) { long hi = 1L << (digits * 4); return Long.toHexString(hi | (val & (hi - 1))).substring(1); } /** * Returns a hash code for this"-" "-" * "-" * "-" * * time_low = 4* * time_mid = 2* * time_high_and_version = 2* * variant_and_sequence = 2* * node = 6* * hexOctet = * hexDigit = * "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" * | "a" | "b" | "c" | "d" | "e" | "f" * | "A" | "B" | "C" | "D" | "E" | "F" *
UUID.
*
* @return a hash code value for this UUID.
*/
public int hashCode()
{
if (hashCode == -1)
{
hashCode = (int) ((mostSigBits >> 32) ^
mostSigBits ^
(leastSigBits >> 32) ^
leastSigBits);
}
return hashCode;
}
/**
* Compares this object to the specified object. The result is
* true if and only if the argument is not
* null, is a UUID object, has the same variant,
* and contains the same value, bit for bit, as this UUID.
*
* @param obj the object to compare with.
* @return true if the objects are the same;
* false otherwise.
*/
public boolean equals(Object obj)
{
if (!(obj instanceof UUID))
return false;
if (((UUID) obj).variant() != this.variant())
return false;
UUID id = (UUID) obj;
return (mostSigBits == id.mostSigBits &&
leastSigBits == id.leastSigBits);
}
// Comparison Operations
/**
* Compares this UUID with the specified UUID.
*
* The first of two UUIDs follows the second if the most significant * field in which the UUIDs differ is greater for the first UUID. * * @param val UUID to which this UUID is to be compared. * @return -1, 0 or 1 as this UUID is less than, equal * to, or greater than val. */ public int compareTo(UUID val) { // The ordering is intentionally set up so that the UUIDs // can simply be numerically compared as two numbers return (this.mostSigBits < val.mostSigBits ? -1 : (this.mostSigBits > val.mostSigBits ? 1 : (this.leastSigBits < val.leastSigBits ? -1 : (this.leastSigBits > val.leastSigBits ? 1 : 0)))); } /** * Reconstitute the UUID instance from a stream (that is, * deserialize it). This is necessary to set the transient fields * to their correct uninitialized value so they will be recomputed * on demand. */ private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException { in.defaultReadObject(); // Set "cached computation" fields to their initial values version = -1; variant = -1; timestamp = -1; sequence = -1; node = -1; hashCode = -1; } }
Map工具类
package com.jarvis.base.util;
import java.util.Map;
/**
*
*
* @Title: MapHelper.java
* @Package com.jarvis.base.util
* @Description:Map工具类
* @version V1.0
*/
public class MapHelper {
/**
* 获得字串值
*
* @param name
* 键值名称
* @return 若不存在，则返回空字串
*/
public static String getString(Map map, String name) {
if (name == null || name.equals("")) {
return "";
}
String value = "";
if (map.containsKey(name) == false) {
return "";
}
Object obj = map.get(name);
if (obj != null) {
value = obj.toString();
}
obj = null;
return value;
}
/**
* 返回整型值
*
* @param name
* 键值名称
* @return 若不存在，或转换失败，则返回0
*/
public static int getInt(Map map, String name) {
if (name == null || name.equals("")) {
return 0;
}
int value = 0;
if (map.containsKey(name) == false) {
return 0;
}
Object obj = map.get(name);
if (obj == null) {
return 0;
}
if (!(obj instanceof Integer)) {
try {
value = Integer.parseInt(obj.toString());
} catch (Exception ex) {
ex.printStackTrace();
System.err.println("name[" + name + "]对应的值不是数字，返回0");
value = 0;
}
} else {
value = ((Integer) obj).intValue();
obj = null;
}
return value;
}
/**
* 获取长整型值
*
* @param name
* 键值名称
* @return 若不存在，或转换失败，则返回0
*/
public static long getLong(Map map, String name) {
if (name == null || name.equals("")) {
return 0;
}
long value = 0;
if (map.containsKey(name) == false) {
return 0;
}
Object obj = map.get(name);
if (obj == null) {
return 0;
}
if (!(obj instanceof Long)) {
try {
value = Long.parseLong(obj.toString());
} catch (Exception ex) {
ex.printStackTrace();
System.err.println("name[" + name + "]对应的值不是数字，返回0");
value = 0;
}
} else {
value = ((Long) obj).longValue();
obj = null;
}
return value;
}
/**
* 获取Float型值
*
* @param name
* 键值名称
* @return 若不存在，或转换失败，则返回0
*/
public static float getFloat(Map map, String name) {
if (name == null || name.equals("")) {
return 0;
}
float value = 0;
if (map.containsKey(name) == false) {
return 0;
}
Object obj = map.get(name);
if (obj == null) {
return 0;
}
if (!(obj instanceof Float)) {
try {
value = Float.parseFloat(obj.toString());
} catch (Exception ex) {
ex.printStackTrace();
System.err.println("name[" + name + "]对应的值不是数字，返回0");
value = 0;
}
} else {
value = ((Float) obj).floatValue();
obj = null;
}
return value;
}
/**
* 获取Double型值
*
* @param name
* 键值名称
* @return 若不存在，或转换失败，则返回0
*/
public static double getDouble(Map map, String name) {
if (name == null || name.equals("")) {
return 0;
}
double value = 0;
if (map.containsKey(name) == false) {
return 0;
}
Object obj = map.get(name);
if (obj == null) {
return 0;
}
if (!(obj instanceof Double)) {
try {
value = Double.parseDouble(obj.toString());
} catch (Exception ex) {
ex.printStackTrace();
System.err.println("name[" + name + "]对应的值不是数字，返回0");
value = 0;
}
} else {
value = ((Double) obj).doubleValue();
obj = null;
}
return value;
}
/**
* 获取Bool值
*
* @param name
* 键值名称
* @return 若不存在，或转换失败，则返回false
*/
public static boolean getBoolean(Map map, String name) {
if (name == null || name.equals("")) {
return false;
}
boolean value = false;
if (map.containsKey(name) == false) {
return false;
}
Object obj = map.get(name);
if (obj == null) {
return false;
}
if (obj instanceof Boolean) {
return ((Boolean) obj).booleanValue();
}
value = Boolean.valueOf(obj.toString()).booleanValue();
obj = null;
return value;
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。