Joshua Bloch is the author of Effective Java and coauthor of Java Puzzlers and Java Concurrency in Practice. He is an occasional professor a Carnegie Mellon University. He was formerly the chief Java architect at Google, and a distinguished engineer at Sun Microsystems. He led the design and implementation of numerous Java platform features, including the Java 5 language enhancements and the Java Collections Framework. He holds a Ph.D. in computer science from Carnegie Mellon University and a B.S. in computer science from Columbia University.