java/src/main/com/google/apphosting/base/VersionId.java

   1 package com.google.apphosting.base;
   2
   3 import java.util.regex.Matcher;
   4 import java.util.regex.Pattern;
   5
   6 /**
   7  * A parsed Version Id.
   8  *
   9  */
  10 public class VersionId {
  11   public static final String DEFAULT_ENGINE_ID = "default";
  12   public static final String BUILTINS_PREFIX = "ah-builtin-";
  13
  14   private static final int ENGINE_ID_MAX_LENGTH = 63;
  15   private static final int ENGINE_VERSION_ID_MAX_LENGTH = 100;
  16   private static final int MINOR_VERSION_ID_LENGTH = 20;
  17
  18   private static final String ENGINE_ID_RE =
  19       String.format("[a-z\\d][a-z\\d\\-]{0,%d}", ENGINE_ID_MAX_LENGTH - 1);
  20
  21   private static final String ENGINE_VERSION_ID_RE =
  22       String.format("[a-z\\d][a-z\\d\\-]{0,%d}", ENGINE_VERSION_ID_MAX_LENGTH - 1);
  23
  24   private static final String MAJOR_VERSION_RE =
  25       String.format("(?:(?:(%s):)?)(%s)", ENGINE_ID_RE, ENGINE_VERSION_ID_RE);
  26
  27   private static final String FULL_VERSION_RE =
  28       String.format("(%s)(\\.(\\d{1,%d}))?",  MAJOR_VERSION_RE, MINOR_VERSION_ID_LENGTH);
  29
  30   private static final Pattern FULL_VERSION_PATTERN = Pattern.compile(FULL_VERSION_RE);
  31
  32   private final String versionId;
  33   private final String majorVersion;
  34   private final String engineId;
  35   private final String engineVersionId;
  36   private final String minorVersion;
  37
  38   /**
  39    * Create a new VersionId based on an versionId formatted as follows:
  40    *
  41    * [(engine):](engine version)[.(minor version)]
  42    *
  43    * @param versionId The versionId to parse.
  44    */
  45   private VersionId(String versionId) {
  46     if (versionId == null) {
  47       throw new NullPointerException();
  48     }
  49     Matcher matcher = FULL_VERSION_PATTERN.matcher(versionId);
  50     if (!matcher.matches()) {
  51       throw new IllegalArgumentException("Malformed versionId: " + versionId);
  52     }
  53     this.versionId = versionId;
  54     this.majorVersion = matcher.group(1);
  55     this.engineId = matcher.group(2) == null ? DEFAULT_ENGINE_ID : matcher.group(2);
  56     this.engineVersionId = matcher.group(3);
  57     this.minorVersion = matcher.group(5);
  58   }
  59
  60   /**
  61    * @return the majorVersion
  62    */
  63   public String getMajorVersion() {
  64     return majorVersion;
  65   }
  66
  67   /**
  68    * @return the minorVersion or {@code null} if no minor version was present.
  69    */
  70   public String getMinorVersion() {
  71     return minorVersion;
  72   }
  73
  74   /**
  75    * @return the serverId
  76    */
  77   public String getEngineId() {
  78     return engineId;
  79   }
  80
  81   /**
  82    * @return the serverId
  83    */
  84   public String getEngineVersionId() {
  85     return engineVersionId;
  86   }
  87   /**
  88    * @return the versionId
  89    */
  90   public String getVersionId() {
  91     return versionId;
  92   }
  93
  94   public static VersionId parse(String versionId) {
  95     return new VersionId(versionId);
  96   }
  97 }