Claude
c5c435ae20
Co-Authored-By: Claude Sonnet 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_017ic4b5DfjBGLBr7F5km2AN
44 lines
1.4 KiB
Plaintext
44 lines
1.4 KiB
Plaintext
=== Q01 Why is Java platform independent? ===
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magic = CAFEBABE
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class file major version = 69
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=== Q02 JDK vs JRE vs JVM ===
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running on Java 25
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JVM: OpenJDK 64-Bit Server VM
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compiler available: true
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=== Q03 Primitive types and their sizes ===
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byte 1 byte, -128 to 127
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short 2 bytes, -32768 to 32767
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int 4 bytes, -2147483648 to 2147483647
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long 8 bytes, -9223372036854775808 to 9223372036854775807
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float 4 bytes, double 8 bytes, char 2 bytes
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field defaults: 0, false, null
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=== Q04 Type casting and overflow ===
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7 / 2 = 3, (double) 7 / 2 = 3.5
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(byte) 130 = -126
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Integer.MAX_VALUE + 1 = -2147483648
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c + 1 = 66, (char) (c + 1) = B
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0.1 + 0.2 = 0.30000000000000004
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Math.addExact: integer overflow
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=== Q05 Autoboxing and the Integer cache ===
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127 == 127 -> true
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128 == 128 -> false
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128 equals 128 -> true
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Long 127 equals Integer 127 -> false
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=== Q06 Is Java pass by value or pass by reference? ===
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after reassign: original
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after mutate: original + mutated
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=== Q07 static variables, static blocks and initialisation order ===
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static block runs once, when the class loads
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instance block runs before each constructor body
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constructor #1
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instance block runs before each constructor body
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constructor #2
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=== Q08 final, finally and finalize ===
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final array contents changed: 99
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in try
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finally always runs
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Object.finalize forRemoval = true, since 9
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=== Q09 Stack vs heap ===
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heap array length = 1000000
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StackOverflowError after many frames: true
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